Zakażenie mrsa
Etiologia i przyczyny

Metycylinooporne gronkowce złociste (MRSA) to szczepy Staphylococcus aureus wykazujące oporność na antybiotyki beta-laktamowe, w tym metycylinę, penicyliny (amoksycylina, ampicylina), cefalosporyny (np. cefepim) oraz karbapenemy (meropenem, imipenem). Oporność ta wynika z obecności genu mecA kodującego białko PBP2A o zmniejszonym powinowactwie do beta-laktamów, przenoszonego przez element genetyczny SCCmec. Epidemiologicznie wyróżnia się trzy główne typy MRSA: HA-MRSA (związane z opieką zdrowotną), CA-MRSA (pozaszpitalne) oraz LA-MRSA (związane z hodowlą zwierząt). Wzrost częstości zakażeń MRSA jest znaczący – od 2% zakażeń gronkowcowych 30 lat temu do 64% w 2003 roku, z dominacją zakażeń szpitalnych (85%). Szczepy CA-MRSA cechują się większą zjadliwością, m.in. dzięki produkcji leukocydyny Panton-Valentine (PVL), choć ich oporność jest zwykle mniejsza niż HA-MRSA. Nosicielstwo MRSA dotyczy około 2% populacji, a bakterie mogą przetrwać na powierzchniach od 7 dni do 7 miesięcy, co sprzyja transmisji zarówno bezpośredniej (kontakt skóra-skóra), jak i pośredniej (skażone przedmioty).

Rozwój oporności MRSA jest konsekwencją niewłaściwego stosowania antybiotyków, w tym terapii infekcji wirusowych, niepełnych kuracji oraz samodzielnego przyjmowania leków. Czynniki ryzyka zakażeń HA-MRSA obejmują długotrwałą hospitalizację, obecność urządzeń medycznych, immunosupresję oraz wcześniejsze leczenie antybiotykami. Z kolei CA-MRSA dotyczy osób zdrowych, narażonych na kontakt skóra-skóra, życie w zatłoczonych warunkach oraz uszkodzenia skóry. Szczepy LA-MRSA przenoszone są ze zwierząt gospodarskich na ludzi, co stanowi rosnące zagrożenie. Wzrost oporności, w tym pojawienie się szczepów VISA (vancomycin intermediate S. aureus), komplikuje leczenie i zwiększa śmiertelność. MRSA jest jednym z głównych patogenów odpowiedzialnych za zgony związane z opornością na antybiotyki, powodując ponad 100 000 zgonów globalnie w 2019 roku. Skuteczne zwalczanie MRSA wymaga interdyscyplinarnego podejścia uwzględniającego aspekty mikrobiologiczne, genetyczne, epidemiologiczne i kliniczne.

  1. Zakażenie MRSA – Etiologia
    1. Bakteriologia i epidemiologia
    2. Genetyczne podstawy oporności
    3. Czynniki zjadliwości
  2. Przyczyny powstawania MRSA
    1. Nadużywanie antybiotyków
    2. Mechanizmy adaptacji bakterii
    3. Czynniki ryzyka zakażenia MRSA
  3. Drogi transmisji MRSA
    1. Kontakt bezpośredni
    2. Kontakt pośredni
    3. Nosicielstwo i kolonizacja
  4. MRSA w środowiskach wysokiego ryzyka
    1. Placówki opieki zdrowotnej
    2. Społeczność
    3. Środowisko hodowli zwierząt
  5. Rosnące zagrożenie – ewolucja MRSA
  6. Podsumowanie etiologii MRSA
    1. Kolejne rozdziały

Zakażenie MRSA – Etiologia

Metycylinooporne gronkowce złociste (MRSA – methicillin-resistant Staphylococcus aureus) to rodzaj bakterii, które wykazują oporność na antybiotyki beta-laktamowe, w tym metycylinę i inne powszechnie stosowane antybiotyki, takie jak penicyliny (amoksycylina, ampicylina), cefalosporyny (np. cefepim) oraz karbapenemy (meropenem, imipenem)1. MRSA powoduje te same rodzaje zakażeń, co zwykłe szczepy Staphylococcus aureus, jednak są one trudniejsze do leczenia ze względu na ograniczone możliwości terapeutyczne23.

Bakteriologia i epidemiologia

Staphylococcus aureus (gronkowiec złocisty) jest powszechnym typem bakterii występującym na skórze i w jamach nosowych około 25-30% zdrowych osób4. Według danych Centrum Kontroli i Zapobiegania Chorobom (CDC), około 5% populacji jest nosicielami szczepów MRSA, mimo że nie wykazują objawów chorobowych56. Te bakterie mogą przetrwać w ekstremalnych warunkach, w tym wysuszenie, ekstremalne temperatury oraz działanie kwasu żołądkowego7.

MRSA można podzielić na dwie główne kategorie w zależności od środowiska, w którym zostało nabyte zakażenie8:

  • HA-MRSA (healthcare-associated MRSA) – zakażenia związane z opieką zdrowotną, nabywane w szpitalach, domach opieki i innych placówkach medycznych9
  • CA-MRSA (community-associated MRSA) – zakażenia nabywane w środowisku pozaszpitalnym10
  • LA-MRSA (livestock-associated MRSA) – zakażenia związane z hodowlą zwierząt gospodarskich1112

Badania wskazują, że częstość występowania zakażeń MRSA wzrosła znacząco w ciągu ostatnich dekad. Jeszcze 30 lat temu MRSA odpowiadał za zaledwie 2% zakażeń gronkowcowych, a już w 2003 roku odsetek ten wzrósł do 64%13. Większość przypadków MRSA (około 85%) jest związana z placówkami opieki zdrowotnej, podczas gdy około 14% występuje u osób bez niedawnej ekspozycji na środowisko medyczne14.

Genetyczne podstawy oporności

Metycylinooporność u Staphylococcus aureus wynika z obecności genu mecA, zlokalizowanego na chromosomie bakteryjnym w regionie zwanym Staphylococcal Cassette Chromosome mec (SCCmec)1516. Gen ten koduje zmienione białko wiążące penicylinę (PBP2A), które wykazuje zmniejszone powinowactwo do antybiotyków beta-laktamowych1718.

Oporność na metycylinę została nabyta przez bakterie S. aureus w wyniku mutacji chromosomalnej lub poprzez horyzontalny transfer genów. Co istotne, jest to jeden z nielicznych klinicznie istotnych przykładów oporności na leki przenoszonej przez bakteriofagi (zjawisko transdukcji)19. Nabycie SCCmec przez wrażliwe na metycylinę S. aureus (MSSA) prowadzi do powstania różnych genetycznie linii MRSA20.

Szczepy CA-MRSA i HA-MRSA różnią się na poziomie genetycznym i posiadają odmienne właściwości biologiczne21. Badania sugerują, że CA-MRSA nie ewoluowało z HA-MRSA, ale powstało niezależnie, gdy nowe szczepy MRSA zintegrowały SCCmec z MSSA22. Szczepy CA-MRSA są zazwyczaj łatwiejsze do leczenia, ale bardziej zjadliwe niż HA-MRSA23.

Czynniki zjadliwości

Zwiększona wirulencja niektórych szczepów MRSA, szczególnie CA-MRSA, jest przedmiotem intensywnych badań. Jednym z kluczowych czynników zjadliwości jest leukocydyna Panton-Valentine (PVL), białko toksyczne dla komórek układu odpornościowego, które zwalczają infekcje2425. PVL jest szczególnie związana z martwiczym zapaleniem płuc oraz zakażeniami skóry i tkanek miękkich26.

Warto zauważyć, że chociaż istnieje silny związek epidemiologiczny między szczepami CA-MRSA zawierającymi PVL a określonymi rodzajami zakażeń, rola PVL w zwiększonej zjadliwości MRSA jest złożona i kontrowersyjna, wymagająca dalszych badań27.

Przyczyny powstawania MRSA

Nadużywanie antybiotyków

Główną przyczyną powstawania szczepów MRSA jest wieloletnie niewłaściwe stosowanie antybiotyków2829. Przez dziesięciolecia antybiotyki były przepisywane na przeziębienia, grypę i inne infekcje wirusowe, które nie reagują na te leki30. Niektóre czynniki przyczyniające się do rozwoju oporności na antybiotyki obejmują:

  • Stosowanie antybiotyków na infekcje wirusowe, które nie reagują na te leki31
  • Nieukończenie pełnej kuracji antybiotykowej przepisanej przez lekarza32
  • Przyjmowanie antybiotyków bez recepty33
  • Pomijanie dawek podczas przyjmowania antybiotyków34

Nawet gdy antybiotyki są stosowane właściwie, przyczyniają się do rozwoju bakterii opornych na leki, ponieważ nie niszczą każdego drobnoustroju, który jest ich celem35. Bakterie ewoluują bardzo szybko, więc drobnoustroje, które przeżyją leczenie jednym antybiotykiem, szybko uczą się opierać innym36.

Mechanizmy adaptacji bakterii

Bakterie potrzebują się rozmnażać, aby zapewnić sobie przetrwanie. Gdy ta zdolność jest zagrożona, np. przez ekspozycję na antybiotyki, mikroorganizmy adaptują się i ewoluują, aby przezwyciężyć blokadę ich rozmnażania37. Antybiotyki działają poprzez celowanie w procesy replikacji bakterii. Oporność rozwija się, gdy bakterie potrafią dostosować te procesy, aby ominąć działanie antybiotyku38.

Za każdym razem, gdy bakterie wywołują wybuch choroby, mają potencjał do wytwarzania mutacji, które sprzyjają ich przetrwaniu. Oznacza to, że bakterie stają się bardziej zakaźne i trudniejsze do leczenia39. W przypadku MRSA, zdolność do oporności na wiele antybiotyków jest przekazywana między bakteriami S. aureus przez bakteriofagi40.

Czynniki ryzyka zakażenia MRSA

Zakażenie MRSA może dotknąć każdego, jednak niektóre osoby są bardziej narażone. Czynniki ryzyka różnią się w zależności od typu MRSA (HA-MRSA vs CA-MRSA):

Czynniki ryzyka HA-MRSA

Zakażenia HA-MRSA są związane z opieką zdrowotną i najczęściej występują u pacjentów, którzy414243:

  • Przebywają długo w szpitalu (zwłaszcza jeśli są leczeni z powodu poważnej choroby)
  • Mają wszczepione urządzenia medyczne (np. cewniki, linie dożylne)
  • Przeszli niedawną operację lub zabieg chirurgiczny
  • Mieszkają w placówkach opieki długoterminowej lub domach opieki
  • Mają przewlekłą chorobę nerek/są na hemodializie
  • Mają osłabiony układ odpornościowy (np. z powodu HIV, leczenia nowotworów)
  • Są w trakcie antybiotykoterapii

W środowisku szpitalnym pacjenci są narażeni na zwiększone ryzyko zakażenia MRSA z kilku powodów44:

  • Wielu hospitalizowanych pacjentów przyjmuje antybiotyki, które mogą zmniejszyć normalną florę bakteryjną organizmu, dając szczepom MRSA przewagę
  • Wielu pacjentów w szpitalach ma przerwania ciągłości skóry (rany pooperacyjne, linie dożylne i cewniki), które mogą umożliwić bakteriom wniknięcie do tkanek lub krwiobiegu
Czynniki ryzyka CA-MRSA

Zakażenia CA-MRSA nabywane są poza środowiskiem szpitalnym i mogą dotyczyć osób zdrowych. Czynniki ryzyka obejmują454647:

  • Częsty kontakt skóry ze skórą (np. podczas uprawiania sportów kontaktowych)
  • Życie w zatłoczonych warunkach (np. koszary wojskowe, więzienia, akademiki)
  • Dzielenie się przedmiotami osobistymi (ręczniki, maszynki do golenia)
  • Posiadanie ran, zadrapań lub innych uszkodzeń skóry
  • Wykonywanie tatuaży lub piercingu
  • Iniekcje narkotykowe
  • Niedawne stosowanie antybiotyków
  • Wcześniejsze zakażenie MRSA
  • Niska higiena osobista lub środowiskowa

CDC zidentyfikowało pięć czynników (tzw. „5C”), które ułatwiają rozprzestrzenianie się MRSA w społeczności48:

  • Crowding – zatłoczenie
  • Contact – częsty kontakt skóry ze skórą
  • Compromised skin – uszkodzenia skóry (np. nacięcia lub otarcia)
  • Contaminated – skażone przedmioty i powierzchnie
  • Cleanliness – brak czystości

Drogi transmisji MRSA

Kontakt bezpośredni

MRSA przenosi się najczęściej przez bezpośredni kontakt skóra-skóra z osobą zainfekowaną lub będącą nosicielem bakterii4950. Bakterie MRSA mogą przenosić się z osoby na osobę podczas kontaktu fizycznego, szczególnie gdy istnieje rana lub uszkodzenie skóry, przez które bakterie mogą wniknąć do organizmu51.

Zakażenie MRSA zazwyczaj występuje, gdy bakterie przedostaną się przez przerwanie ciągłości skóry (np. cięcie, otarcie, rana) do organizmu52. Bakterie mogą się również przenosić z zakażonej skóry na ręczniki, mydła i pościel, a następna osoba korzystająca z tych przedmiotów może przejąć bakterie53.

Kontakt pośredni

MRSA może przetrwać na różnych powierzchniach i przedmiotach przez dłuższy czas, co umożliwia pośrednią transmisję. Bakterie mogą rozprzestrzeniać się poprzez5455:

  • Kontakt z przedmiotami lub powierzchniami skażonymi MRSA (np. sprzęt sportowy, sprzęt medyczny, klamki)
  • Dzielenie się osobistymi przedmiotami, takimi jak ręczniki, maszynki do golenia, ubrania
  • Niedostatecznie odkażone narzędzia chirurgiczne lub sprzęt medyczny

W środowisku MRSA może przetrwać od siedmiu dni do siedmiu miesięcy na twardych powierzchniach, przy czym długość przeżycia zależy od warunków, takich jak temperatura i wilgotność56.

Nosicielstwo i kolonizacja

Ważnym aspektem epidemiologii MRSA jest zjawisko nosicielstwa (kolonizacji), gdy osoba nosi bakterie MRSA na skórze lub w nosie, ale nie ma objawów zakażenia57. Nosiciele mogą przenosić bakterie na innych ludzi i powierzchnie, nie zdając sobie z tego sprawy.

Według badań58:

  • Około 1/3 populacji (30-50%) jest nosicielami S. aureus w nosie lub na skórze
  • Około 2% populacji jest nosicielami MRSA

Nosiciele MRSA mogą w pewnych okolicznościach rozwinąć aktywne zakażenie, zwłaszcza jeśli ich układ odpornościowy zostanie osłabiony lub gdy dojdzie do przerwania ciągłości skóry59.

MRSA w środowiskach wysokiego ryzyka

Placówki opieki zdrowotnej

Zakażenia MRSA są najczęściej związane z opieką zdrowotną (HA-MRSA) i występują u pacjentów, którzy przebywali w szpitalu, domu opieki lub innej placówce medycznej60. W tych środowiskach MRSA jest jedną z głównych przyczyn zakażeń związanych z opieką zdrowotną, w tym zakażeń miejsca operowanego, zakażeń krwi i zapalenia płuc61.

Czynniki zwiększające ryzyko zakażenia HA-MRSA w placówkach opieki zdrowotnej obejmują62:

  • Długotrwała hospitalizacja
  • Wszczepione urządzenia medyczne
  • Osłabiony układ odpornościowy
  • Niedostateczna higiena
  • Nadużywanie antybiotyków

W domach opieki i placówkach długoterminowej opieki zdrowotnej MRSA stanowi szczególne zagrożenie ze względu na dużą liczbę mieszkańców z osłabionym układem odpornościowym oraz częste stosowanie antybiotyków i urządzeń inwazyjnych63.

Społeczność

CA-MRSA, czyli zakażenia MRSA nabywane w środowisku pozaszpitalnym, stają się coraz bardziej powszechne64. Zakażenia te występują u osób, które nie miały niedawnego kontaktu z placówkami opieki zdrowotnej.

Miejsca, w których CA-MRSA może się łatwiej rozprzestrzeniać, obejmują6566:

  • Instytucje sportowe i drużyny sportowe – zakażenia mogą rozprzestrzeniać się przez bezpośredni kontakt podczas gry lub przez skażony sprzęt sportowy i odzież
  • Żłobki i przedszkola
  • Placówki wojskowe i więzienia – ze względu na zatłoczenie i ograniczone możliwości higieny
  • Akademiki – z powodu bliskiego kontaktu i dzielenia się przedmiotami osobistymi

Środowisko hodowli zwierząt

W ostatnich latach odnotowano wzrost zakażeń MRSA związanych z hodowlą zwierząt (LA-MRSA). Stosowanie antybiotyków w hodowli zwierząt zwiększa ryzyko rozwoju MRSA wśród zwierząt gospodarskich i innych zwierząt, które mogą przebywać w ich pobliżu67.

Szczepy MRSA, takie jak ST398 i CC398, mogą być przenoszone ze zwierząt na ludzi6869. Zwierzęta domowe również mogą być nosicielami i przenosić MRSA na ludzi7071.

Rosnące zagrożenie – ewolucja MRSA

MRSA stanowi coraz większe wyzwanie dla zdrowia publicznego ze względu na ciągłą ewolucję i adaptację bakterii. Bakterie gronkowca złocistego nadal ewoluują i zaczynają wykazywać oporność na dodatkowe antybiotyki72.

Szczególnie niepokojące są szczepy VISA (vancomycin intermediate Staphylococcus aureus), które zaczynają rozwijać oporność na wankomycynę – antybiotyk często stosowany jako „ostatnia deska ratunku” w leczeniu ciężkich zakażeń MRSA73.

Konsekwencje oporności na antybiotyki stanowią istotne zagrożenie dla zdrowia publicznego74:

  • Zakażenia opornymi bakteriami mogą prowadzić do dłuższej hospitalizacji
  • Bardziej skomplikowane leczenie
  • Wyższe wskaźniki śmiertelności
  • Zwiększone koszty opieki zdrowotnej

Według raportu opublikowanego w The Lancet, Staphylococcus aureus jest jednym z sześciu głównych patogenów odpowiedzialnych za zgony związane z opornością na antybiotyki75. MRSA spowodował ponad 100 000 zgonów na całym świecie z powodu oporności na środki przeciwdrobnoustrojowe w 2019 roku76.

Podsumowanie etiologii MRSA

Zakażenie MRSA jest wynikiem skomplikowanej interakcji między czynnikami mikrobiologicznymi, genetycznymi i środowiskowymi77. Główne przyczyny i mechanizmy rozwoju MRSA to:

  1. Nadużywanie i niewłaściwe stosowanie antybiotyków, które doprowadziło do selekcji szczepów opornych78
  2. Genetyczne mechanizmy oporności, w tym nabycie genu mecA, kodującego zmienione białko wiążące penicylinę (PBP2A)79
  3. Zdolność bakterii do szybkiej adaptacji i ewolucji w odpowiedzi na presję antybiotykową80
  4. Łatwość przenoszenia się bakterii między ludźmi i z powierzchni skażonych81
  5. Zwiększona zjadliwość niektórych szczepów MRSA, zwłaszcza CA-MRSA82

Zrozumienie złożonej etiologii MRSA jest kluczowe dla opracowania skutecznych strategii zapobiegania i leczenia tych zakażeń. Wymaga to kompleksowego podejścia, które uwzględnia aspekty mikrobiologiczne, genetyczne, epidemiologiczne i kliniczne tego patogenu83.

Kolejne rozdziały

Zapraszamy do dalszego czytania naszego leksykonu.

Wybierz kolejny rozdział z menu poniżej, aby otworzyć nową podstronę kompedium wiedzy i uzyskać szczegółowe informację o leku, substancji lub chorobie.

  1. 10.04.2026
  2. www.leksykon.com.pl

Materiały źródłowe

  • #1 MRSA: Causes, Symptoms, Diagnosis, Treatment & Prevention
    https://my.clevelandclinic.org/health/diseases/11633-methicillin-resistant-staphylococcus-aureus-mrsa
    Methicillin is a type of antibiotic related to penicillin. But despite MRSAs name (methicillin-resistant Staphylococcus aureus), MRSA strains are usually resistant to many types of antibiotics, including: Other penicillin drugs, like amoxicillin and ampicillin. Cephalosporins, like cefepime. Carbapenems, like meropenem and imipenem. […] HA-MRSA is usually resistant to more types of antibiotics than CA-MRSA.
  • #2 MRSA. Methicillin (meticillin) resistant Staphylococcus aureus
    https://dermnetnz.org/topics/methicillin-resistant-staphylococcus-aureus
    MRSA is the term used for bacteria of the Staphylococcus aureus group that are resistant to the usual antibiotics used in the treatment of infections with such organisms. […] Resistance to methicillin is due to the presence of the mec gene, situated on Staphylococcal Cassette Chromosome mec (SCCmec). This alters the site at which methicillin binds to kill the organism. […] Infections caused by MRSA are the same as other staphylococcal infections because the organism itself is not any more virulent (or infectious) than usual type S aureus. […] Problems arise in the treatment of overt infections with MRSA because antibiotic choice is very limited. […] Most MRSA infections occur in wounds (eg surgical wounds), skin (eg intravenous access sites), or in the bloodstream. […] Community acquired MRSA infections mostly occur: In overcrowded places, due to frequent contact of skin and to sharing things.
  • #3 MRSA: Causes, Symptoms, Diagnosis, Treatment & Prevention
    https://my.clevelandclinic.org/health/diseases/11633-methicillin-resistant-staphylococcus-aureus-mrsa
    MRSA (methicillin-resistant Staphylococcus aureus) is a type of bacteria that many antibiotics dont work on. MRSA most often causes skin infections, but it can also cause serious illnesses that are hard to treat. […] MRSA (methicillin-resistant Staphylococcus aureus) is a type of bacteria thats developed defense mechanisms (resistance) to antibiotics. MRSA infections are hard to treat because very few antibiotics are effective against them. MRSA most often causes skin infections but it can also cause serious infections in your lungs, heart and bloodstream. […] Strains of Staphylococcus aureus develop antibiotic resistance for many reasons. Sometimes, it happens naturally in the environment. Other times, it happens when the bacteria develop defense mechanisms to block or destroy antibiotic drugs. In hospitals and other healthcare settings, bacteria can become resistant to antibiotics that are used often.
  • #4 Methicillin-Resistant Staphylococcus Aureus (MRSA) | BCM
    https://www.bcm.edu/departments/molecular-virology-and-microbiology/emerging-infections-and-biodefense/specific-agents/mrsa
    Staphylococcus aureus, often referred to as staph, is a common type of bacterium that is found in about 25 to 30 percent of healthy people, primarily on the skin or in the nose. […] Some people become infected with staph bacteria indicating that the bacteria are present and cause disease. […] Although staph bacteria do not usually cause infection, they can bring about disease if they penetrate through a break in the skin or through mucous membranes. […] In the past few decades, a more dangerous form of staph has emerged. This form is known as methicillin-resistant Staphylococcus aureus and is usually referred to by the acronym MRSA. […] MRSA is categorized by the setting in which it is acquired. […] The first type, healthcare-acquired MRSA (HA-MRSA), has been recognized since the 1960s.
  • #5 MRSA infection – Symptoms & causes – Mayo Clinic
    https://www.mayoclinic.org/diseases-conditions/mrsa/symptoms-causes/syc-20375336
    Methicillin-resistant Staphylococcus aureus (MRSA) infection is caused by a type of staph bacteria that’s become resistant to many of the antibiotics used to treat ordinary staph infections. […] Different varieties of Staphylococcus aureus bacteria, commonly called „staph,” exist. Staph bacteria are normally found on the skin or in the nose of about one-third of the population. The bacteria are generally harmless unless they enter the body through a cut or other wound, and even then they usually cause only minor skin problems in healthy people. […] According to the Centers for Disease Control and Prevention, around 5% of the population chronically carries the type of staph bacteria known as MRSA. […] MRSA is the result of decades of often unnecessary antibiotic use. For years, antibiotics have been prescribed for colds, flu and other viral infections that don’t respond to these drugs. Even when antibiotics are used appropriately, they contribute to the rise of drug-resistant bacteria because they don’t destroy every germ they target. Bacteria live on an evolutionary fast track, so germs that survive treatment with one antibiotic soon learn to resist others.
  • #6 MRSA Infection – St. Michael’s Elite Hospital
    https://24hrer.com/mrsa-infection/
    MRSA infection is a type of staph infection that can cause skin infections and other problems. MRSA stands for methicillin-resistant Staphylococcus aureus, which means it is resistant to antibiotics called beta-lactams such as penicillin and amoxicillin. MRSA spreads easily in the community and healthcare settings. […] The most common type of MRSA disease is a skin infection or abscesses caused by direct contact with another person who has MRSA on the skin surface (such as from wounds). […] According to the Centers for Disease Control and Prevention, around 5% of the population is infected with MRSA, a kind of staph bacterium. The causes of the infection are not completely known but it is believed that MRSA arises when staph bacteria become resistant to antibiotics. […] Antibiotics contribute to the growth of drug-resistant germs even when they are administered properly since they do not kill every germ they target. Bacteria evolve quickly, so bacteria that survive treatment with one antibiotic quickly learn to resist others.
  • #7 Staph infections – Symptoms & causes – Mayo Clinic
    https://www.mayoclinic.org/diseases-conditions/staph-infections/symptoms-causes/syc-20356221
    Staph infections are caused by staphylococcus bacteria. […] Many people carry staph bacteria on their skin or in their nose and never develop staph infections. However, if you develop a staph infection, there’s a good chance that it’s from bacteria you’ve been carrying around for some time. […] Staph bacteria can also be spread from person to person. Because staph bacteria are so hardy, they can live on objects such as pillowcases or towels long enough to transfer to the next person who touches them. […] Staph bacteria can make you sick by causing an infection. You can also become sick from the toxins produced by the bacteria. […] Staph bacteria can survive: Drying, Extremes of temperature, Stomach acid.
  • #8 Methicillin-resistant Staphylococcus aureus – Wikipedia
    https://en.wikipedia.org/wiki/Methicillin-resistant_Staphylococcus_aureus
    The terms HA-MRSA (healthcare-associated or hospital-acquired MRSA), CA-MRSA (community-associated MRSA), and LA-MRSA (livestock-associated MRSA) reflect this. […] Antibiotic use in livestock increases the risk that MRSA will develop among the livestock and other animals that may reside near them; strains MRSA ST398 and CC398 are transmissible to humans. […] Domestic pets are susceptible to MRSA infection by transmission from their owners; conversely, MRSA-infected pets can also transmit MRSA to humans. […] Acquisition of SCCmec in methicillin-sensitive S. aureus (MSSA) gives rise to a number of genetically different MRSA lineages. […] Community-acquired MRSA (CA-MRSA) strains emerged in late 1990 to 2000, infecting healthy people who had not been in contact with healthcare facilities.
  • #9 Methicillin-resistant Staphylococcus aureus – Wikipedia
    https://en.wikipedia.org/wiki/Methicillin-resistant_Staphylococcus_aureus
    Methicillin-resistant Staphylococcus aureus (MRSA) is a group of gram-positive bacteria that are genetically distinct from other strains of Staphylococcus aureus. MRSA is responsible for several difficult-to-treat infections in humans. It caused more than 100,000 deaths worldwide attributable to antimicrobial resistance in 2019. […] MRSA is any strain of S. aureus that has developed (through natural selection) or acquired (through horizontal gene transfer) a multiple drug resistance to beta-lactam antibiotics. […] MRSA infection is common in hospitals, prisons, and nursing homes, where people with open wounds, invasive devices such as catheters, and weakened immune systems are at greater risk of healthcare-associated infection. […] MRSA began as a hospital-acquired infection but has become community-acquired, as well as livestock-acquired.
  • #10 Methicillin-resistant Staphylococcus aureus – Wikipedia
    https://en.wikipedia.org/wiki/Methicillin-resistant_Staphylococcus_aureus
    The terms HA-MRSA (healthcare-associated or hospital-acquired MRSA), CA-MRSA (community-associated MRSA), and LA-MRSA (livestock-associated MRSA) reflect this. […] Antibiotic use in livestock increases the risk that MRSA will develop among the livestock and other animals that may reside near them; strains MRSA ST398 and CC398 are transmissible to humans. […] Domestic pets are susceptible to MRSA infection by transmission from their owners; conversely, MRSA-infected pets can also transmit MRSA to humans. […] Acquisition of SCCmec in methicillin-sensitive S. aureus (MSSA) gives rise to a number of genetically different MRSA lineages. […] Community-acquired MRSA (CA-MRSA) strains emerged in late 1990 to 2000, infecting healthy people who had not been in contact with healthcare facilities.
  • #11 Methicillin-resistant Staphylococcus aureus – Wikipedia
    https://en.wikipedia.org/wiki/Methicillin-resistant_Staphylococcus_aureus
    The terms HA-MRSA (healthcare-associated or hospital-acquired MRSA), CA-MRSA (community-associated MRSA), and LA-MRSA (livestock-associated MRSA) reflect this. […] Antibiotic use in livestock increases the risk that MRSA will develop among the livestock and other animals that may reside near them; strains MRSA ST398 and CC398 are transmissible to humans. […] Domestic pets are susceptible to MRSA infection by transmission from their owners; conversely, MRSA-infected pets can also transmit MRSA to humans. […] Acquisition of SCCmec in methicillin-sensitive S. aureus (MSSA) gives rise to a number of genetically different MRSA lineages. […] Community-acquired MRSA (CA-MRSA) strains emerged in late 1990 to 2000, infecting healthy people who had not been in contact with healthcare facilities.
  • #12 Livestock-Associated Methicillin-Resistant Staphylococcus aureus (MRSA) as Causes of Human Infection and Colonization in Germany | PLOS One
    https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0055040
    Pigs, cattle and poultry are colonized with MRSA and the zoonotic transmission of such MRSA to humans via direct animal contact, environmental contaminations or meat are a matter of concern. […] Livestock-associated (LA) MRSA are mostly belonging to clonal complex (CC) 398 as defined by multilocus sequence typing. […] The pathogenicity of MRSA CC398 for humans has been documented in a variety of reports describing cases of endocarditis, otomastoiditis, pneumonia or wound infections. […] Our findings indicate that LA-MRSA are a major cause for human infection and stress the need for close surveillance. […] Although LA-MRSA CC398 predominates, the occurrence of putative LA-MRSA from other clonal lineages should be monitored. […] Important questions related to the epidemiology of MRSA CC398 are 1.) whether they lead to an increase of the overall incidence of MRSA colonization or infection among humans and 2.) whether MRSA CC398 are strictly involving persons with direct livestock contact or how often MRSA CC398 is spreading from these persons onwards in the general population.
  • #13 Methicillin-Resistant Staphylococcus Aureus (MRSA) | BCM
    https://www.bcm.edu/departments/molecular-virology-and-microbiology/emerging-infections-and-biodefense/specific-agents/mrsa
    The incidence of disease caused by MRSA bacteria is increasing worldwide. […] Thirty years ago, MRSA accounted for 2 percent of staph infections. […] By 2003, 64 percent of staph infections were caused by MRSA. […] The majority of MRSA cases, 85 percent, were associated with healthcare facilities, while approximately 14 percent occurred in individuals with no known exposure to healthcare. […] The staph bacterium continues to evolve and is beginning to show resistance to additional antibiotics. […] The rising problem of resistance of staph bacteria to methicillin and other antibiotics is part of a larger issue that greatly concerns healthcare professionals. […] The emergence of antimicrobial-resistant organisms is making it more difficult to treat a variety of infectious diseases.
  • #14 Methicillin-Resistant Staphylococcus Aureus (MRSA) | BCM
    https://www.bcm.edu/departments/molecular-virology-and-microbiology/emerging-infections-and-biodefense/specific-agents/mrsa
    The incidence of disease caused by MRSA bacteria is increasing worldwide. […] Thirty years ago, MRSA accounted for 2 percent of staph infections. […] By 2003, 64 percent of staph infections were caused by MRSA. […] The majority of MRSA cases, 85 percent, were associated with healthcare facilities, while approximately 14 percent occurred in individuals with no known exposure to healthcare. […] The staph bacterium continues to evolve and is beginning to show resistance to additional antibiotics. […] The rising problem of resistance of staph bacteria to methicillin and other antibiotics is part of a larger issue that greatly concerns healthcare professionals. […] The emergence of antimicrobial-resistant organisms is making it more difficult to treat a variety of infectious diseases.
  • #15 MRSA. Methicillin (meticillin) resistant Staphylococcus aureus
    https://dermnetnz.org/topics/methicillin-resistant-staphylococcus-aureus
    MRSA is the term used for bacteria of the Staphylococcus aureus group that are resistant to the usual antibiotics used in the treatment of infections with such organisms. […] Resistance to methicillin is due to the presence of the mec gene, situated on Staphylococcal Cassette Chromosome mec (SCCmec). This alters the site at which methicillin binds to kill the organism. […] Infections caused by MRSA are the same as other staphylococcal infections because the organism itself is not any more virulent (or infectious) than usual type S aureus. […] Problems arise in the treatment of overt infections with MRSA because antibiotic choice is very limited. […] Most MRSA infections occur in wounds (eg surgical wounds), skin (eg intravenous access sites), or in the bloodstream. […] Community acquired MRSA infections mostly occur: In overcrowded places, due to frequent contact of skin and to sharing things.
  • #16 Methicillin-Resistant Staphylococcus aureus – StatPearls – NCBI Bookshelf
    https://www.ncbi.nlm.nih.gov/books/NBK482221/
    Methicillin resistance has occurred in S. aureus by mutation of a penicillin-binding protein, a chromosome-encoded protein. This type of resistance is transferred between S. aureus organisms by bacteriophages. This is one of the only medically relevant examples of chromosome-mediated drug resistance by phage transduction. […] MRSA infection is one of the leading causes of hospital-acquired infections and is commonly associated with significant morbidity, mortality, length of stay, and cost burden. […] MRSA infections can be further divided into hospital-associated (HA-MRSA) infections and community-associated (CA-MRSA) infections. They differ not only in respect to their clinical features and molecular biology but also to their antibiotic susceptibility and treatment.
  • #17 Pathogenesis of Methicillin-Resistant Staphylococcus aureus Infection
    https://pmc.ncbi.nlm.nih.gov/articles/PMC2474459/
    Staphylococcus aureus is a versatile pathogen capable of causing a wide range of human diseases. […] Although methicillin-resistant S. aureus (MRSA) strains are not necessarily more virulent than methicillin-sensitive S. aureus strains, some MRSA strains contain factors or genetic backgrounds that may enhance their virulence or may enable them to cause particular clinical syndromes. […] Certain MRSA strains appear to contain particular factors or genetic backgrounds that enhance their virulence or enable them to cause particular clinical syndromes. […] Methicillin resistance is conferred by the mecA gene, which encodes a penicillin-binding protein (PBP2A) with decreased affinity for -lactam antibiotics. […] The basis for the apparent increased virulence of CA-MRSA strains is incompletely understood.
  • #18 Methicillin-Resistant Staphylococcus Aureus (MRSA) | BCM
    https://www.bcm.edu/departments/molecular-virology-and-microbiology/emerging-infections-and-biodefense/specific-agents/mrsa
    They need to know which strains are present within a community at any point in time, to which antibiotics the strains are resistant, and the severity of disease caused by the circulating strains. […] Dr. Timothy Palzkill, professor of Pharmacology and Chemical Biology and Molecular Virology and Microbiology, and his research team have been studying mechanisms of resistance to methicillin and other beta-lactam antibiotics. […] Gram-positive bacteria acquire resistance to beta-lactam antibiotics through the production of a protein called PBP2a, which is able to avoid the inhibitory effects of the antibiotics. […] This is the mechanism by which MRSA is able to persist despite treatment with multiple beta-lactam antibiotics.
  • #19 Methicillin-Resistant Staphylococcus aureus – StatPearls – NCBI Bookshelf
    https://www.ncbi.nlm.nih.gov/books/NBK482221/
    Methicillin resistance has occurred in S. aureus by mutation of a penicillin-binding protein, a chromosome-encoded protein. This type of resistance is transferred between S. aureus organisms by bacteriophages. This is one of the only medically relevant examples of chromosome-mediated drug resistance by phage transduction. […] MRSA infection is one of the leading causes of hospital-acquired infections and is commonly associated with significant morbidity, mortality, length of stay, and cost burden. […] MRSA infections can be further divided into hospital-associated (HA-MRSA) infections and community-associated (CA-MRSA) infections. They differ not only in respect to their clinical features and molecular biology but also to their antibiotic susceptibility and treatment.
  • #20 Methicillin-resistant Staphylococcus aureus – Wikipedia
    https://en.wikipedia.org/wiki/Methicillin-resistant_Staphylococcus_aureus
    The terms HA-MRSA (healthcare-associated or hospital-acquired MRSA), CA-MRSA (community-associated MRSA), and LA-MRSA (livestock-associated MRSA) reflect this. […] Antibiotic use in livestock increases the risk that MRSA will develop among the livestock and other animals that may reside near them; strains MRSA ST398 and CC398 are transmissible to humans. […] Domestic pets are susceptible to MRSA infection by transmission from their owners; conversely, MRSA-infected pets can also transmit MRSA to humans. […] Acquisition of SCCmec in methicillin-sensitive S. aureus (MSSA) gives rise to a number of genetically different MRSA lineages. […] Community-acquired MRSA (CA-MRSA) strains emerged in late 1990 to 2000, infecting healthy people who had not been in contact with healthcare facilities.
  • #21 Methicillin-Resistant Staphylococcus Aureus (MRSA) | BCM
    https://www.bcm.edu/departments/molecular-virology-and-microbiology/emerging-infections-and-biodefense/specific-agents/mrsa
    The incidence of this infection has been increasing over time, with patients who have had surgery, medical devices implanted, or weakened immune systems being particularly at risk. […] Of greater concern is a second type of MRSA which appeared in the 1990s and is known as community-acquired MRSA (CA-MRSA). […] CA-MRSA occurs outside of hospital settings and usually manifests itself as a skin infection in an otherwise healthy individual. […] CA-MRSA can develop into a more serious, life-threatening illness. […] The best defense against MRSA is to maintain good hygiene, including frequent and thorough hand washing, and to avoid the sharing of personal care items. […] HA-MRSA and CA-MRSA differ at the genetic level and have distinct biologic properties. […] These differences suggest that CA-MRSA strains may spread more easily from person to person or cause more skin disease than HA-MRSA.
  • #22 Methicillin-resistant Staphylococcus aureus – Wikipedia
    https://en.wikipedia.org/wiki/Methicillin-resistant_Staphylococcus_aureus
    Researchers suggest that CA-MRSA did not evolve from HA-MRSA. […] This is further proven by molecular typing of CA-MRSA strains and genome comparison between CA-MRSA and HA-MRSA, which indicate that novel MRSA strains integrated SCCmec into MSSA separately on its own. […] Community-acquired MRSA is more easily treated and more virulent than hospital-acquired MRSA (HA-MRSA). […] The genetic mechanism for the enhanced virulence in CA-MRSA remains an active area of research.
  • #23 Methicillin-resistant Staphylococcus aureus – Wikipedia
    https://en.wikipedia.org/wiki/Methicillin-resistant_Staphylococcus_aureus
    Researchers suggest that CA-MRSA did not evolve from HA-MRSA. […] This is further proven by molecular typing of CA-MRSA strains and genome comparison between CA-MRSA and HA-MRSA, which indicate that novel MRSA strains integrated SCCmec into MSSA separately on its own. […] Community-acquired MRSA is more easily treated and more virulent than hospital-acquired MRSA (HA-MRSA). […] The genetic mechanism for the enhanced virulence in CA-MRSA remains an active area of research.
  • #24 MRSA Infection: Symptoms, Causes, Treatment, Contagious, Pictures & Superbug
    https://www.medicinenet.com/mrsa_infection/article.htm
    A deadly complication of MRSA is a deep infection, necrotizing fasciitis, which causes rapid spread and destruction of human tissues. Some but not all strains of MRSA are more likely to behave like „flesh-eating bacteria.” It is impossible to predict which MRSA infection will be „flesh-eating.” […] In general, there are two major strains of MRSA, „community-acquired or CA-MRSA and „hospital-acquired” or HA-MRSA. CA-MRSA differs from HA-MRSA in that it is often resistant to fewer antibiotics. […] MRSA bacteria often have a variety of „virulence factors” that are responsible for this. Some of these are „leucocidin” proteins that are toxic to immune cells that fight infections or cause more inflammation and tissue damage; Panton-Valentine leucocidin (PVL) protein is a well-known example that is produced by the USA300 strain of CA-MRSA.
  • #25 CA-MRSA – Infectious Disease Services of Georgia | Atlanta Specialists
    https://www.infectiousdiseaseservices.com/ca-mrsa.php
    Staph infections are caused by a common bacteria carried on the skin or in the nose of a high percentage of individuals. […] Over the years, Staph bacteria have developed resistance to penicillin (PRSA) and methicillin (MRSA). […] MRSA was recognized in the early 1960s but it has been limited to hospitals and institutional settings until recently. […] Over the past 6 years a new genetic strain of MRSA (USA 300) has emerged in the Atlanta area. […] Two main problems that CA-MRSA presents to patients and physicians are 1) increased virulence leading to more serious infection and 2) resistance to the commonly used antibiotics. […] Skin infections with CA-MRSA often have black centers causing misdiagnosis as spider bites. […] This may be caused by a new toxin (Panton-Valentine leukocidin) that causes white cell destruction and tissue death.
  • #26 Pathogenesis of Methicillin-Resistant Staphylococcus aureus Infection
    https://pmc.ncbi.nlm.nih.gov/articles/PMC2474459/
    The genes and mechanisms by which CA-MRSA strains may cause aggressive disease are discussed in the sections that follow. […] There is a strong epidemiological association between PVL and the emergence of CA-MRSA infections. […] Given this evidence and the strong epidemiological association between PVL-containing CA-MRSA strains and necrotizing pneumonia and skin and soft-tissue infections, it is plausible that PVL is partly responsible for the enhanced virulence of CA-MRSA. […] The association of PVL with enhanced S. aureus virulence is complex and controversial and warrants further investigation. […] The role of many virulence factors in the pathogenesis of staphylococcal disease is unclear. […] To date, there is no compelling evidence that MRSA, in general, is more virulent than MSSA.
  • #27 Pathogenesis of Methicillin-Resistant Staphylococcus aureus Infection
    https://pmc.ncbi.nlm.nih.gov/articles/PMC2474459/
    The genes and mechanisms by which CA-MRSA strains may cause aggressive disease are discussed in the sections that follow. […] There is a strong epidemiological association between PVL and the emergence of CA-MRSA infections. […] Given this evidence and the strong epidemiological association between PVL-containing CA-MRSA strains and necrotizing pneumonia and skin and soft-tissue infections, it is plausible that PVL is partly responsible for the enhanced virulence of CA-MRSA. […] The association of PVL with enhanced S. aureus virulence is complex and controversial and warrants further investigation. […] The role of many virulence factors in the pathogenesis of staphylococcal disease is unclear. […] To date, there is no compelling evidence that MRSA, in general, is more virulent than MSSA.
  • #28 MRSA Infection: Symptoms, Causes, Treatments, Prevention
    https://resources.healthgrades.com/right-care/infections-and-contagious-diseases/mrsa-infection
    MRSA results from many years of incorrect antibiotic use. Antibiotics work by targeting the replication processes of bacteria. Resistance develops when bacteria can adjust these processes to get around the antibiotic. Bacteria can make these changes quickly and learn with each new antibiotic exposure. […] Some people can use antibiotics incorrectly when taking them for viral infections, such as a cold or flu. Antibiotics can only treat bacterial infections. However, even with legitimate bacterial infections, people can still use them incorrectly. For example, they do not finish the entire course of antibiotics their doctor prescribes. […] In each of these cases, bacteria get exposure to the antibiotic and an opportunity to learn how to grow even in the presence of the drug. Some bacteria survive and pass on the information they gain from the exposure as they replicate.
  • #29 MRSA infection – Symptoms & causes – Mayo Clinic
    https://www.mayoclinic.org/diseases-conditions/mrsa/symptoms-causes/syc-20375336
    Methicillin-resistant Staphylococcus aureus (MRSA) infection is caused by a type of staph bacteria that’s become resistant to many of the antibiotics used to treat ordinary staph infections. […] Different varieties of Staphylococcus aureus bacteria, commonly called „staph,” exist. Staph bacteria are normally found on the skin or in the nose of about one-third of the population. The bacteria are generally harmless unless they enter the body through a cut or other wound, and even then they usually cause only minor skin problems in healthy people. […] According to the Centers for Disease Control and Prevention, around 5% of the population chronically carries the type of staph bacteria known as MRSA. […] MRSA is the result of decades of often unnecessary antibiotic use. For years, antibiotics have been prescribed for colds, flu and other viral infections that don’t respond to these drugs. Even when antibiotics are used appropriately, they contribute to the rise of drug-resistant bacteria because they don’t destroy every germ they target. Bacteria live on an evolutionary fast track, so germs that survive treatment with one antibiotic soon learn to resist others.
  • #30 MRSA infection – Symptoms & causes – Mayo Clinic
    https://www.mayoclinic.org/diseases-conditions/mrsa/symptoms-causes/syc-20375336
    Methicillin-resistant Staphylococcus aureus (MRSA) infection is caused by a type of staph bacteria that’s become resistant to many of the antibiotics used to treat ordinary staph infections. […] Different varieties of Staphylococcus aureus bacteria, commonly called „staph,” exist. Staph bacteria are normally found on the skin or in the nose of about one-third of the population. The bacteria are generally harmless unless they enter the body through a cut or other wound, and even then they usually cause only minor skin problems in healthy people. […] According to the Centers for Disease Control and Prevention, around 5% of the population chronically carries the type of staph bacteria known as MRSA. […] MRSA is the result of decades of often unnecessary antibiotic use. For years, antibiotics have been prescribed for colds, flu and other viral infections that don’t respond to these drugs. Even when antibiotics are used appropriately, they contribute to the rise of drug-resistant bacteria because they don’t destroy every germ they target. Bacteria live on an evolutionary fast track, so germs that survive treatment with one antibiotic soon learn to resist others.
  • #31 MRSA Infection: Symptoms, Causes, Treatments, Prevention
    https://resources.healthgrades.com/right-care/infections-and-contagious-diseases/mrsa-infection
    MRSA results from many years of incorrect antibiotic use. Antibiotics work by targeting the replication processes of bacteria. Resistance develops when bacteria can adjust these processes to get around the antibiotic. Bacteria can make these changes quickly and learn with each new antibiotic exposure. […] Some people can use antibiotics incorrectly when taking them for viral infections, such as a cold or flu. Antibiotics can only treat bacterial infections. However, even with legitimate bacterial infections, people can still use them incorrectly. For example, they do not finish the entire course of antibiotics their doctor prescribes. […] In each of these cases, bacteria get exposure to the antibiotic and an opportunity to learn how to grow even in the presence of the drug. Some bacteria survive and pass on the information they gain from the exposure as they replicate.
  • #32 Learning about MRSA: A guide for Patients – MN Dept. of Health
    https://www.health.state.mn.us/diseases/staph/mrsa/book.html
    You dont follow your doctors directions when taking antibiotics (for example you stop taking your antibiotics before finishing a prescription or you skip doses) […] You frequently get cuts or scrapes on your skin (Your skin serves as a barrier to infection. When the skin gets damaged staph bacteria can enter and increase your risk for infection.) […] There are two ways you can have MRSA. […] You can have an active infection. An active infection means you have symptoms. This is usually a boil, a sore, or an infected cut that is red, swollen, or pus-filled. […] You can be a carrier. If you are a carrier you do not have symptoms that you can see, but you still have MRSA bacteria living in your nose or on your skin. […] Many people with active infections are treated effectively, and no longer have MRSA.
  • #33 Learning about MRSA: A guide for Patients – MN Dept. of Health
    https://www.health.state.mn.us/diseases/staph/mrsa/book.html
    Staphylococci or staph bacteria commonly live on the skin and in the nose. Usually, staph bacteria dont cause any harm. […] However, if they get inside the body they can cause an infection. […] When common antibiotics dont kill the staph bacteria, it means the bacteria have become resistant to those antibiotics. […] This type of staph is called MRSA (Methicillin-Resistant Staphylococcus aureus). […] MRSA was first identified in the 1960s and was mainly found in hospitals and nursing homes. […] In the late 1990s, a new type of MRSA was identified. […] This type of MRSA is becoming more common among children and adults who do not have medical conditions. […] You may increase your chances of getting MRSA if: […] You take antibiotics a lot […] You take antibiotics without a prescription
  • #34 Learning about MRSA: A guide for Patients – MN Dept. of Health
    https://www.health.state.mn.us/diseases/staph/mrsa/book.html
    You dont follow your doctors directions when taking antibiotics (for example you stop taking your antibiotics before finishing a prescription or you skip doses) […] You frequently get cuts or scrapes on your skin (Your skin serves as a barrier to infection. When the skin gets damaged staph bacteria can enter and increase your risk for infection.) […] There are two ways you can have MRSA. […] You can have an active infection. An active infection means you have symptoms. This is usually a boil, a sore, or an infected cut that is red, swollen, or pus-filled. […] You can be a carrier. If you are a carrier you do not have symptoms that you can see, but you still have MRSA bacteria living in your nose or on your skin. […] Many people with active infections are treated effectively, and no longer have MRSA.
  • #35 MRSA Infection – St. Michael’s Elite Hospital
    https://24hrer.com/mrsa-infection/
    MRSA infection is a type of staph infection that can cause skin infections and other problems. MRSA stands for methicillin-resistant Staphylococcus aureus, which means it is resistant to antibiotics called beta-lactams such as penicillin and amoxicillin. MRSA spreads easily in the community and healthcare settings. […] The most common type of MRSA disease is a skin infection or abscesses caused by direct contact with another person who has MRSA on the skin surface (such as from wounds). […] According to the Centers for Disease Control and Prevention, around 5% of the population is infected with MRSA, a kind of staph bacterium. The causes of the infection are not completely known but it is believed that MRSA arises when staph bacteria become resistant to antibiotics. […] Antibiotics contribute to the growth of drug-resistant germs even when they are administered properly since they do not kill every germ they target. Bacteria evolve quickly, so bacteria that survive treatment with one antibiotic quickly learn to resist others.
  • #36 MRSA infection – Symptoms & causes – Mayo Clinic
    https://www.mayoclinic.org/diseases-conditions/mrsa/symptoms-causes/syc-20375336
    Methicillin-resistant Staphylococcus aureus (MRSA) infection is caused by a type of staph bacteria that’s become resistant to many of the antibiotics used to treat ordinary staph infections. […] Different varieties of Staphylococcus aureus bacteria, commonly called „staph,” exist. Staph bacteria are normally found on the skin or in the nose of about one-third of the population. The bacteria are generally harmless unless they enter the body through a cut or other wound, and even then they usually cause only minor skin problems in healthy people. […] According to the Centers for Disease Control and Prevention, around 5% of the population chronically carries the type of staph bacteria known as MRSA. […] MRSA is the result of decades of often unnecessary antibiotic use. For years, antibiotics have been prescribed for colds, flu and other viral infections that don’t respond to these drugs. Even when antibiotics are used appropriately, they contribute to the rise of drug-resistant bacteria because they don’t destroy every germ they target. Bacteria live on an evolutionary fast track, so germs that survive treatment with one antibiotic soon learn to resist others.
  • #37 Methicillin-Resistant Staphylococcus Aureus (MRSA) | BCM
    https://www.bcm.edu/departments/molecular-virology-and-microbiology/emerging-infections-and-biodefense/specific-agents/mrsa
    Drug resistance occurs because microbes, such as staph bacteria, need to reproduce to ensure their survival. […] When this ability is threatened, as when they are exposed to antibiotics, microbes adapt and evolve to overcome the block to their reproduction. […] However, drug resistance adaptations can be accelerated by human actions, particularly by the overuse and inappropriate use of antibiotics. […] The consequences of antimicrobial resistance pose a significant concern to scientists and medical professionals. […] Infection with drug-resistant organisms can lead to increased and longer hospital stays, more complicated treatment, more deaths, and higher healthcare costs. […] Scientists would further like to understand the genetic changes in MRSA that allow the bacterium to cause serious illness in otherwise healthy individuals.
  • #38 MRSA Infection: Symptoms, Causes, Treatments, Prevention
    https://resources.healthgrades.com/right-care/infections-and-contagious-diseases/mrsa-infection
    MRSA results from many years of incorrect antibiotic use. Antibiotics work by targeting the replication processes of bacteria. Resistance develops when bacteria can adjust these processes to get around the antibiotic. Bacteria can make these changes quickly and learn with each new antibiotic exposure. […] Some people can use antibiotics incorrectly when taking them for viral infections, such as a cold or flu. Antibiotics can only treat bacterial infections. However, even with legitimate bacterial infections, people can still use them incorrectly. For example, they do not finish the entire course of antibiotics their doctor prescribes. […] In each of these cases, bacteria get exposure to the antibiotic and an opportunity to learn how to grow even in the presence of the drug. Some bacteria survive and pass on the information they gain from the exposure as they replicate.
  • #39 MRSA symptoms: What they are, causes, treatment, and more
    https://www.medicalnewstoday.com/articles/mrsa-symptoms
    Methicillin-resistant Staphylococcus aureus (MRSA) is a bacterium that does not respond to several antibiotics. […] The Centers for Disease Control and Prevention (CDC) state that the bacteria typically causes skin infections. However, MRSA can also lead to infections in other parts of the body. […] Staphylococcus aureus bacteria became resistant to methicillin in the 1950s after the introduction of the methicillin (a member of the penicillin family) antibiotic. […] MRSA is a dangerous pathogen because it is very contagious, difficult to treat, and can cause severe infection in some people. […] Each time the bacteria causes an outbreak, it has the potential to produce mutations that promote its survival. This means that the bacteria become more infectious and more difficult to treat. […] Researchers are trying to determine the mechanisms that lead to MRSA mutations that allow the bacteria to thrive.
  • #40 Methicillin-Resistant Staphylococcus aureus – StatPearls – NCBI Bookshelf
    https://www.ncbi.nlm.nih.gov/books/NBK482221/
    Methicillin resistance has occurred in S. aureus by mutation of a penicillin-binding protein, a chromosome-encoded protein. This type of resistance is transferred between S. aureus organisms by bacteriophages. This is one of the only medically relevant examples of chromosome-mediated drug resistance by phage transduction. […] MRSA infection is one of the leading causes of hospital-acquired infections and is commonly associated with significant morbidity, mortality, length of stay, and cost burden. […] MRSA infections can be further divided into hospital-associated (HA-MRSA) infections and community-associated (CA-MRSA) infections. They differ not only in respect to their clinical features and molecular biology but also to their antibiotic susceptibility and treatment.
  • #41
  • #42 MRSA
    https://www.nhs.uk/conditions/mrsa/
    MRSA usually lives harmlessly on the skin and mainly spreads through touch. […] This can happen if you touch a person with MRSA, or something theyve touched. […] MRSA will only cause an infection if it spreads inside the body. […] MRSA infections can affect anyone, but you may be more at risk if you: […] have long stays in hospital (especially if youre being treated for a serious condition) […] have a break or opening in your skin, for example for a drip into a vein, a cut from surgery, a serious burn or wound, or other damage to your skin […] have a weakened immune system (for example, because of a condition such as HIV or treatment such as chemotherapy).
  • #43 MRSA: Causes, Symptoms, and Treatment
    https://patient.info/infections/mrsa-leaflet
    Infection with MRSA bacteria mainly occurs in people who are already ill in hospital. […] It can be difficult to treat MRSA, as the bacteria are resistant to most types of antibiotic medicines. […] Many people are carriers of MRSA without even realising it, as MRSA often does not cause symptoms in healthy people. […] MRSA has become much more common since the 1980s. MRSA is now the cause of over 4 in 10 bloodstream infections with S. aureus. […] MRSA occurs most commonly in people who are already in hospital, especially if they have been in hospital for a length of time. […] People who are more prone to MRSA are those who are very ill, who are HIV-positive or have wounds or open sores (for example, bedsores or burns). […] MRSA can also cause infections in people outside hospital but much less commonly than in hospitalised people. […] Infections with MRSA can sometimes become more severe than they may otherwise have been.
  • #44 Causes and Symptoms of HA-MRSA – MN Dept. of Health
    https://www.health.state.mn.us/diseases/staph/mrsa/hamrsa/basics.html
    HA-MRSA is a type of Methicillin-resistant Staphylococcus aureus infection. […] Hospitalized patients are at increased risk for MRSA infection for several reasons: […] Many hospitalized patients are taking antibiotics that can decrease the normal flora found on the body, giving MRSA strains an advantage. […] Many patients in hospitals have breaks in their skin (surgical wounds, intravenous lines (IVs), and catheters) that can allow bacteria to enter underlying tissues or the bloodstream. […] There is a possibility for longer lasting or more severe infections with CA-MRSA if the initial antibiotic prescribed is not capable of killing the bacteria.
  • #45 MRSA: Treatment, causes, and symptoms
    https://www.medicalnewstoday.com/articles/10634
    MRSA results from infection with bacterial strains that have acquired resistance to particular antibiotics. […] MRSA is a form of contagious bacterial infection. […] These resistant bacteria are called methicillin-resistant staphylococcus aureus, or MRSA. […] MRSA frequently causes illness in people with a compromised immune system who spend time in the hospital and other healthcare facilities. […] MRSA is less common outside a healthcare setting. […] Factors that increase the risk of developing community-associated MRSA include: living with a lot of people, such as on a military base, in jail, or on a campus; having regular skin-to-skin interaction with other people; doing a job or hobby that increases the risk of cuts or grazes to the skin; regularly injecting drugs; having low adherence to personal or environmental hygiene; previous antibiotic use.
  • #46 MRSA Infection: Symptoms, Treatment, Causes & Pictures
    https://www.emedicinehealth.com/mrsa_infection/article_em.htm
    MRSA is the abbreviation for methicillin-resistant Staphylococcus aureus. Staphylococcus is a group of bacteria, familiarly known as staph or staph bacteria, that can cause a multitude of diseases as a result of infection of various tissues of the body. […] Within 1-2 years, Staphylococcus aureus bacteria (S. aureus) started to be isolated that were resistant to methicillin. These S. aureus bacteria were then termed methicillin-resistant or MRSA. MRSA bacteria usually show resistance to many antibiotics. […] MRSA bacteria can be transmitted by direct (though skin and body fluids) and indirect contact (from towels, diapers, and toys) to uninfected people. […] Statistics show that CA-MRSA is the predominant MRSA type found in the population. […] Risk factors for getting MRSA staph infections in healthy people include: Playing contact sports, Sharing towels or other personal items, Having any condition that suppresses immune system function (for example, HIV, cancer, or chemotherapy), Unsanitary or crowded living conditions (dormitories or military barracks), Being a health care worker, Age.
  • #47 MRSA Infections
    https://ph.health.mil/topics/discond/diseases/Pages/MRSA-Community.aspx
    Staph bacteria that cannot be treated with several types of common antibiotics are called methicillin resistant Staphylococcus aureus, or „MRSA”. […] If a skin infection is caused by MRSA, it can be more severe and more difficult to treat because of its resistance to commonly used antibiotics. […] When people who are healthy and have not been in a hospital get a MRSA infection it is often called „community acquired”, or CA-MRSA. […] About 2% of people carry MRSA bacteria on their skin or in their nose, usually without any problems. […] People are at higher risk of getting a CA-MRSA skin infection when they participate in activities or live in places that involve crowding, skin-to-skin contact, or sharing of towels, razors, and other personal items.
  • #48 Facts About Methicillin-Resistant Staphylococcus aureus | CloroxPro
    https://www.cloroxpro.com/resource-center/mrsa/
    In healthcare settings, MRSA is one of the leading causes of surgical site infections, bloodstream infections and pneumonia. These can occur in patients who have breaks in the skin that can allow the bacteria to enter the tissues or bloodstream, or in patients taking antibiotics, which can reduce the normal flora on the skin, giving MRSA an advantage. […] The CDC has identified five factors the five Cs that may make it easier for people in locations where these exist to acquire MRSA. These are Crowding, frequent skin-to-skin Contact, Compromised skin (i.e., cuts or abrasions), Contaminated items and surfaces, and lack of Cleanliness. […] For HA-MRSA infections, because MRSA can enter any open wound or break in the skin (e.g., those resulting from IV catheter insertions), anyone who is hospitalized is at risk.
  • #49 MRSA (Methicillin-resistant Staphylococcus aureus) Infection
    https://mydoctor.kaiserpermanente.org/mas/structured-content/Condition_MRSA_Methicillin_Resistant_Staphylococcus_aureus_Infection_-_Medicine.xml?co=/regions/mas
    Methicillin-resistant Staphylococcus aureus (MRSA) infection is caused by Staphylococcus aureus (staph) bacteria. MRSA is most commonly spread through contact with an infected person. […] MRSA is most commonly spread by close contact with an infected person. Bacteria can transfer to another person during skin-to-skin contact. It can also spread from infected skin to towels, soaps, and sheets. The next person using these items may pick up the bacteria. […] MRSA and similar bacteria have developed resistance to commonly used antibiotics. These antibiotics no longer effectively treat MRSA-caused infections. Though some resistance would have happened naturally, modern medicine’s over-use of antibiotics has contributed to strongly resistant bacterial strains such as MRSA.
  • #50 Methicillin-resistant Staphylococcus aureus (MRSA) Basics | MRSA | CDC
    https://www.cdc.gov/mrsa/about/index.html
    MRSA is a type of bacteria that is resistant to several antibiotics. […] MRSA is a type of staph that can be resistant to several antibiotics. […] The risk increases for people with hospitalizations or nursing home stays, skin-to-skin contact with others (such as in contact sports), and exposure to crowded and unhygienic places. […] MRSA infections can cause serious problems in and outside of healthcare settings, including: pneumonia (lung infections), bloodstream infections, surgical site infections, sepsis, the body’s extreme response to an infection (if left untreated), and death (if left untreated). […] MRSA spreads in the community through contact with infected people, wounds, or things that have touched infected skin and are carrying the bacteria. […] Some people who carry MRSA can go on to get a MRSA infection. […] A healthcare provider must send a clinical specimen to a laboratory to determine if MRSA is the cause of an infection. […] While MRSA can be resistant to several antibiotics, meaning these drugs cannot cure the infections, there are antibiotics available to treat MRSA infections.
  • #51 Methicillin-resistant Staphylococcus aureus: MRSA (S. aureus) | Gouvernement du Québec
    https://www.quebec.ca/en/health/health-issues/a-z/staphylococcus-aureus-infection-mrsa
    Methicillin-resistant Staphylococcus aureus, known as MRSA (or Mursa), is a staphylococcus that has become resistant to a number of antibiotics, including methicillin. Given that this antibiotic is not effective for treating MRSA infections, this limits the choice of treatment. MRSA causes the same infections as other staphylococci. […] Taking antibiotics, while necessary for treating infections, disrupts all the bacteria in the body, the good as well as the bad. Because this natural barrier has been weakened, it is much easier for a micro-organism such as MRSA to colonize or infect a person. […] Depending on its nature, a MRSA infection may result in serious complications, such as pneumonia, a bone infection or a bloodstream infection. Some may even be life threatening for infected people. […] MRSA is mainly spread through direct contact with the contaminated hands of a carrier, an infected person, or healthcare personnel, or with contaminated surfaces and objects.
  • #52 MRSA (Staph) Infection: Pictures, Symptoms, Treatment, and Prevention
    https://www.healthline.com/health/mrsa
    Methicillin-resistant Staphylococcus aureus (MRSA) is an infection of Staphylococcus (staph) bacteria. […] However, when they begin to multiply uncontrollably, a MRSA infection can occur. […] MRSA infections typically occur when there’s a cut or break in your skin. MRSA is very contagious and can be spread through direct contact with a person who has the infection. […] CA-MRSA is associated with infections transmitted through close personal contact with a person who has the infection or through direct contact with an infected wound. […] This type of MRSA infection may also develop because of poor hygiene, such as infrequent or improper handwashing. […] HA-MRSA is associated with infections that are contracted in medical facilities, such as hospitals or nursing homes. […] You can also get the infection through contact with contaminated linens or poorly sanitized surgical instruments. […] Symptoms and treatments can vary based on the type of MRSA infection a person has.
  • #53 MRSA (Methicillin-resistant Staphylococcus aureus) Infection
    https://mydoctor.kaiserpermanente.org/mas/structured-content/Condition_MRSA_Methicillin_Resistant_Staphylococcus_aureus_Infection_-_Medicine.xml?co=/regions/mas
    Methicillin-resistant Staphylococcus aureus (MRSA) infection is caused by Staphylococcus aureus (staph) bacteria. MRSA is most commonly spread through contact with an infected person. […] MRSA is most commonly spread by close contact with an infected person. Bacteria can transfer to another person during skin-to-skin contact. It can also spread from infected skin to towels, soaps, and sheets. The next person using these items may pick up the bacteria. […] MRSA and similar bacteria have developed resistance to commonly used antibiotics. These antibiotics no longer effectively treat MRSA-caused infections. Though some resistance would have happened naturally, modern medicine’s over-use of antibiotics has contributed to strongly resistant bacterial strains such as MRSA.
  • #54 MRSA Action UK | Symptoms
    http://mrsaactionuk.net/symptoms.html
    MRSA bacteria are usually spread through skin-to-skin contact with someone who has an MRSA infection or who is colonised by the bacteria. […] The bacteria can also spread through contact with towels, sheets, clothes, dressings or other objects that have been used by someone colonised or infected with MRSA. […] MRSA can survive for long periods on objects or surfaces such as door handles, sinks, floors and cleaning equipment. […] MRSA infections are diagnosed by testing blood, urine or a sample of tissue from the infected area for the presence of MRSA bacteria. […] However, MRSA bacteria are resistant to meticillin (a type of penicillin antibiotic), and usually to some of the other antibiotics that are normally used to treat S. aureus infections. Therefore MRSA infections are more difficult to treat than other bacterial infections. […] MRSA does not usually harm healthy people; for example, it cannot harm pregnant women, children or babies, providing they are fit and healthy.
  • #55 Staphylococcal Infections: MedlinePlus
    https://medlineplus.gov/staphylococcalinfections.html
    Staphylococcus (staph) is a group of bacteria. There are more than 30 types. A type called Staphylococcus aureus causes most infections. […] Some people carry staph bacteria on their skin or in their noses, but they do not get an infection. But if they get a cut or wound, the bacteria can enter the body and cause an infection. […] Staph bacteria can spread from person to person. They can also spread on objects, such as towels, clothing, door handles, athletic equipment, and remotes. […] Some staph infections, such as MRSA (methicillin-resistant Staphylococcus aureus), are resistant to many antibiotics. There are still certain antibiotics that can treat these infections.
  • #56 Facts About Methicillin-Resistant Staphylococcus aureus | CloroxPro
    https://www.cloroxpro.com/resource-center/mrsa/
    Based on 2005 CDC estimates for invasive MRSA infections and data on culture-confirmed CA-MRSA infections, it is likely that there are over 1.3 million MRSA infections in total, of which around 90% were CA-MRSA infections. […] MRSA is generally spread by direct skin-to-skin contact, or by contact with surfaces or shared items such as towels or bedding that have been contaminated through contact with an infected site of someone with a MRSA infection. […] In the environment, S. aureus and MRSA can survive for between seven days and seven months on hard surfaces, with the length of survival dependent on conditions such as temperature and humidity. […] Treatment very often requires the use of antibiotics, but there are only a few antibiotics to which MRSA is susceptible, including the broad-spectrum antibiotic vancomycin.
  • #57 Learning about MRSA: A guide for Patients – MN Dept. of Health
    https://www.health.state.mn.us/diseases/staph/mrsa/book.html
    You dont follow your doctors directions when taking antibiotics (for example you stop taking your antibiotics before finishing a prescription or you skip doses) […] You frequently get cuts or scrapes on your skin (Your skin serves as a barrier to infection. When the skin gets damaged staph bacteria can enter and increase your risk for infection.) […] There are two ways you can have MRSA. […] You can have an active infection. An active infection means you have symptoms. This is usually a boil, a sore, or an infected cut that is red, swollen, or pus-filled. […] You can be a carrier. If you are a carrier you do not have symptoms that you can see, but you still have MRSA bacteria living in your nose or on your skin. […] Many people with active infections are treated effectively, and no longer have MRSA.
  • #58 MRSA Surgical Site Infections: What You Should Know | bioMérieux Living Diagnostics Blog
    https://www.biomerieux.com/corp/en/blog/infectious-diseases/MRSA-surgical-site-infections.html
    In low- and middle-income countries, 11% of patients who undergo surgery are infected in the process. […] However, with antimicrobial resistance on the rise, many infections are becoming more and more difficult to treat. MRSA, or methicillin-resistant Staphylococcus aureus, is a type of S. aureus that has become resistant to many first-line antibiotics and it commonly infects surgical wounds. […] According to a recent report in The Lancet, Staphylococcus aureus is among the six leading pathogens for deaths associated with resistance. MRSA poses a serious threat to public health and safety given its association with significantly high morbidity and mortality. […] Studies show that 1 in 3 people carry S. aureus in their nose and 2 in 100 carry MRSA in their nose. […] The degree of risk for a surgical site infection is related to the type of surgery and whether an infection is present at the time of surgery.
  • #59 Beware: Under the Wrong Conditions, You Can Die from MRSA
    https://www.healthline.com/health/can-you-die-from-mrsa
    Methicillin-resistant Staphylococcus aureus (MRSA) is a type of drug-resistant staph infection. […] MRSA is very contagious. Its transmitted through contact with a person who has the infection or any object or surface that has MRSA on it. […] MRSA only causes an infection when it finds an opening such as a cut and enters your skin or body. […] People who have MRSA but arent sick are said to be colonized. Theyre called carriers, and they can transmit MRSA to others. […] MRSA can infect the inside of your heart. This can quickly damage your heart valves. […] MRSAs more likely to cause an infection when theres a pathway for the bacteria to enter your body. […] Invasive MRSA infections can overwhelm your immune system and can be very hard to treat. Many people die. […] The outlook for invasive MRSA infections depends on the severity. […] Invasive infections are much more serious. They almost always require aggressive treatment with IV antibiotics in the hospital. Even then, you can die from a severe infection.
  • #60 Centre for Health Protection – Methicillin-resistant Staphylococcus Aureus (MRSA) Infection
    https://www.chp.gov.hk/en/healthtopics/content/24/10688.html
    Staphylococcus aureus (S. aureus) is a bacterium that can be found in the nasal cavity and on the skin of some healthy people. […] However, methicillin-resistant S. aureus (MRSA) is a strain of S. aureus that is resistant to antibiotics including methicillin and other commonly used antibiotics such as oxacillin, penicillin, amoxicillin and cephalosporins. […] Improper use of antibiotics is widely recognised as a contributing factor to antibiotic resistance. […] Anyone can carry or get infected with MRSA, the risk increases with crowded environment and activities with frequent skin to skin contact. […] Most MRSA infections occur in people who have been hospitalised, live in residential care homes or have received antibiotic treatment/ invasive procedures in health care settings such as dialysis centres.
  • #61 Facts About Methicillin-Resistant Staphylococcus aureus | CloroxPro
    https://www.cloroxpro.com/resource-center/mrsa/
    In healthcare settings, MRSA is one of the leading causes of surgical site infections, bloodstream infections and pneumonia. These can occur in patients who have breaks in the skin that can allow the bacteria to enter the tissues or bloodstream, or in patients taking antibiotics, which can reduce the normal flora on the skin, giving MRSA an advantage. […] The CDC has identified five factors the five Cs that may make it easier for people in locations where these exist to acquire MRSA. These are Crowding, frequent skin-to-skin Contact, Compromised skin (i.e., cuts or abrasions), Contaminated items and surfaces, and lack of Cleanliness. […] For HA-MRSA infections, because MRSA can enter any open wound or break in the skin (e.g., those resulting from IV catheter insertions), anyone who is hospitalized is at risk.
  • #62 MRSA Infections: Causes, Risks, and Legal Options | 3/10/2025
    https://www.forthepeople.com/blog/mrsa-infections-causes-risks-and-legal-options/
    Methicillin-resistant Staphylococcus aureus (MRSA) infection is a bacterial infection caused by a staph bacteria commonly found in hospitals, nursing homes, and dialysis centers. […] The infection is resistant to many common antibiotics, making it particularly difficult to treat. […] MRSA spreads through direct contact with an infected wound, personal items contaminated with the bacteria, or surfaces that have not been properly disinfected. […] The primary risk factors for MRSA infections include hospitalization, medical devices, weakened immune system, poor hygiene practices, overuse of antibiotics, and close-contact environments. […] If a patient contracts MRSA due to unsanitary hospital conditions, failure to follow infection control protocols, delayed or misdiagnosed MRSA infection, or improper use of antibiotics, they may have grounds to file a medical malpractice lawsuit.
  • #63 MRSA in Nursing Homes – Causes & Diagnosing MRSA
    https://nursinghomesabuse.org/nursing-home-injuries/infections/mrsa/
    MRSA represents a significant danger to nursing home residents, but many people outside the medical field haven’t heard of it. MRSA stands for methicillin-resistant Staphylococcus aureus. The disease is an antibiotic-resistant staph infection. […] According to the Centers for Disease Control & Prevention (CDC), healthcare facilities like nursing homes are particularly vulnerable to the disease because nursing home residents frequently receive inpatient medical care or surgery and have weakened immune systems due to age. […] Further CDC data indicates that around 120,000 MRSA infections occur each year and that approximately 20,000 deaths result from those infections. Many of those infections occur in health care settings like nursing homes. […] Methicillin-resistant Staphylococcus aureus (MRSA) infections occur when a nursing home resident comes into contact with the bacteria. The disease typically spreads by touch between human beings or when someone comes into contact with an item contaminated with the bacteria.
  • #64 Learning about MRSA: A guide for Patients – MN Dept. of Health
    https://www.health.state.mn.us/diseases/staph/mrsa/book.html
    Staphylococci or staph bacteria commonly live on the skin and in the nose. Usually, staph bacteria dont cause any harm. […] However, if they get inside the body they can cause an infection. […] When common antibiotics dont kill the staph bacteria, it means the bacteria have become resistant to those antibiotics. […] This type of staph is called MRSA (Methicillin-Resistant Staphylococcus aureus). […] MRSA was first identified in the 1960s and was mainly found in hospitals and nursing homes. […] In the late 1990s, a new type of MRSA was identified. […] This type of MRSA is becoming more common among children and adults who do not have medical conditions. […] You may increase your chances of getting MRSA if: […] You take antibiotics a lot […] You take antibiotics without a prescription
  • #65 MRSA: Treatment, causes, and symptoms
    https://www.medicalnewstoday.com/articles/10634
    MRSA results from infection with bacterial strains that have acquired resistance to particular antibiotics. […] MRSA is a form of contagious bacterial infection. […] These resistant bacteria are called methicillin-resistant staphylococcus aureus, or MRSA. […] MRSA frequently causes illness in people with a compromised immune system who spend time in the hospital and other healthcare facilities. […] MRSA is less common outside a healthcare setting. […] Factors that increase the risk of developing community-associated MRSA include: living with a lot of people, such as on a military base, in jail, or on a campus; having regular skin-to-skin interaction with other people; doing a job or hobby that increases the risk of cuts or grazes to the skin; regularly injecting drugs; having low adherence to personal or environmental hygiene; previous antibiotic use.
  • #66 Everything You Need to Know About the Superbug MRSA
    https://www.everydayhealth.com/staph-infection/guide/mrsa/
    MRSA stands for methicillin-resistant Staphylococcus aureus, a type of staph bacteria thats resistant to the usual antibiotic drugs used to treat common staph infections. […] Researchers have blamed the development of MRSA on the overprescribing of antibiotics including prescribing them for viral infections, such as colds and the flu. […] The risk factors for acquiring a MRSA infection in a healthcare setting (HA-MRSA) are different from those for an infection in a community setting (CA-MRSA). […] Risk factors for HA-MRSA include: Staying in a Hospital, Invasive Medical Devices, Living in a Long-Term Care Facility. […] Risk factors for CA-MRSA include: Playing Contact Sports, Living in Crowded or Unsanitary Conditions, Male Homosexual Activity, Injecting Illegal Drugs, Getting a Tattoo, Recent Illness or Surgery, Recent Antibiotic Use, History of MRSA Infection or Contact. […] If left untreated, or if an antibiotic used to treat it isnt effective, a MRSA infection may spread. Such an infection may become life-threatening. […] The infection may spread to your: Bones, Joints, Blood, Lungs, Heart valves.
  • #67 Methicillin-resistant Staphylococcus aureus – Wikipedia
    https://en.wikipedia.org/wiki/Methicillin-resistant_Staphylococcus_aureus
    The terms HA-MRSA (healthcare-associated or hospital-acquired MRSA), CA-MRSA (community-associated MRSA), and LA-MRSA (livestock-associated MRSA) reflect this. […] Antibiotic use in livestock increases the risk that MRSA will develop among the livestock and other animals that may reside near them; strains MRSA ST398 and CC398 are transmissible to humans. […] Domestic pets are susceptible to MRSA infection by transmission from their owners; conversely, MRSA-infected pets can also transmit MRSA to humans. […] Acquisition of SCCmec in methicillin-sensitive S. aureus (MSSA) gives rise to a number of genetically different MRSA lineages. […] Community-acquired MRSA (CA-MRSA) strains emerged in late 1990 to 2000, infecting healthy people who had not been in contact with healthcare facilities.
  • #68 Methicillin-resistant Staphylococcus aureus – Wikipedia
    https://en.wikipedia.org/wiki/Methicillin-resistant_Staphylococcus_aureus
    The terms HA-MRSA (healthcare-associated or hospital-acquired MRSA), CA-MRSA (community-associated MRSA), and LA-MRSA (livestock-associated MRSA) reflect this. […] Antibiotic use in livestock increases the risk that MRSA will develop among the livestock and other animals that may reside near them; strains MRSA ST398 and CC398 are transmissible to humans. […] Domestic pets are susceptible to MRSA infection by transmission from their owners; conversely, MRSA-infected pets can also transmit MRSA to humans. […] Acquisition of SCCmec in methicillin-sensitive S. aureus (MSSA) gives rise to a number of genetically different MRSA lineages. […] Community-acquired MRSA (CA-MRSA) strains emerged in late 1990 to 2000, infecting healthy people who had not been in contact with healthcare facilities.
  • #69 Livestock-Associated Methicillin-Resistant Staphylococcus aureus (MRSA) as Causes of Human Infection and Colonization in Germany | PLOS One
    https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0055040
    Pigs, cattle and poultry are colonized with MRSA and the zoonotic transmission of such MRSA to humans via direct animal contact, environmental contaminations or meat are a matter of concern. […] Livestock-associated (LA) MRSA are mostly belonging to clonal complex (CC) 398 as defined by multilocus sequence typing. […] The pathogenicity of MRSA CC398 for humans has been documented in a variety of reports describing cases of endocarditis, otomastoiditis, pneumonia or wound infections. […] Our findings indicate that LA-MRSA are a major cause for human infection and stress the need for close surveillance. […] Although LA-MRSA CC398 predominates, the occurrence of putative LA-MRSA from other clonal lineages should be monitored. […] Important questions related to the epidemiology of MRSA CC398 are 1.) whether they lead to an increase of the overall incidence of MRSA colonization or infection among humans and 2.) whether MRSA CC398 are strictly involving persons with direct livestock contact or how often MRSA CC398 is spreading from these persons onwards in the general population.
  • #70 Methicillin-resistant Staphylococcus aureus – Wikipedia
    https://en.wikipedia.org/wiki/Methicillin-resistant_Staphylococcus_aureus
    The terms HA-MRSA (healthcare-associated or hospital-acquired MRSA), CA-MRSA (community-associated MRSA), and LA-MRSA (livestock-associated MRSA) reflect this. […] Antibiotic use in livestock increases the risk that MRSA will develop among the livestock and other animals that may reside near them; strains MRSA ST398 and CC398 are transmissible to humans. […] Domestic pets are susceptible to MRSA infection by transmission from their owners; conversely, MRSA-infected pets can also transmit MRSA to humans. […] Acquisition of SCCmec in methicillin-sensitive S. aureus (MSSA) gives rise to a number of genetically different MRSA lineages. […] Community-acquired MRSA (CA-MRSA) strains emerged in late 1990 to 2000, infecting healthy people who had not been in contact with healthcare facilities.
  • #71 Methicillin-Resistant Staphylococcus Aureus (MRSA) and Pets – Environmental Epidemiology
    https://www.vdh.virginia.gov/environmental-epidemiology/zoonoses/methicillin-resistant-staphylococcus-aureus-mrsa-and-pets/
    Methicillin-resistant Staphylococcus aureus (MRSA) is a bacteria that is commonly found in nasal passages and skin of humans and multiple animals. […] MRSA has been recovered from animals including horses, dogs, cats, cows, and pigs. Some of these animals have not been exposed to antibiotic therapy and in several of these cases the MRSA infection appears to result from human-to-animal transfer. […] MRSA most commonly causes skin or wound infections. […] Symptoms of a MRSA infection depend on where the infection is located. Infections of the skin are the most common, and cause symptoms such as redness, warmth, pus and a wound that does not heal. […] More serious infections are treated with oral antibiotics.
  • #72 Methicillin-Resistant Staphylococcus Aureus (MRSA) | BCM
    https://www.bcm.edu/departments/molecular-virology-and-microbiology/emerging-infections-and-biodefense/specific-agents/mrsa
    The incidence of disease caused by MRSA bacteria is increasing worldwide. […] Thirty years ago, MRSA accounted for 2 percent of staph infections. […] By 2003, 64 percent of staph infections were caused by MRSA. […] The majority of MRSA cases, 85 percent, were associated with healthcare facilities, while approximately 14 percent occurred in individuals with no known exposure to healthcare. […] The staph bacterium continues to evolve and is beginning to show resistance to additional antibiotics. […] The rising problem of resistance of staph bacteria to methicillin and other antibiotics is part of a larger issue that greatly concerns healthcare professionals. […] The emergence of antimicrobial-resistant organisms is making it more difficult to treat a variety of infectious diseases.
  • #73 MRSA. Methicillin (meticillin) resistant Staphylococcus aureus
    https://dermnetnz.org/topics/methicillin-resistant-staphylococcus-aureus
    Risk factors for severe skin infections with MRSA include: Diabetes with obesity, Prior antibiotics (within 90 days), Chronic kidney disease/hemodialysis, Intravenous drug use, Previous MRSA exposure/infection (within 12 months), Previous hospitalisation (12 months), Human immunodeficiency virus infection or AIDS. […] If untreated, MRSA can lead to sepsis with rash, headaches, muscle aches, chills, fever, chest pain and shortness of breath, and in some cases, the death of the patient. […] There is growing concern about MRSA infections. They appear to be increasing in frequency and displaying resistance to a wider range of antibiotics. […] Of particular concern are the VISA strains of MRSA (vancomycin intermediate susceptibility S aureus). These are beginning to develop resistance to vancomycin, which is currently the most effective antibiotic against MRSA.
  • #74 Methicillin-Resistant Staphylococcus Aureus (MRSA) | BCM
    https://www.bcm.edu/departments/molecular-virology-and-microbiology/emerging-infections-and-biodefense/specific-agents/mrsa
    Drug resistance occurs because microbes, such as staph bacteria, need to reproduce to ensure their survival. […] When this ability is threatened, as when they are exposed to antibiotics, microbes adapt and evolve to overcome the block to their reproduction. […] However, drug resistance adaptations can be accelerated by human actions, particularly by the overuse and inappropriate use of antibiotics. […] The consequences of antimicrobial resistance pose a significant concern to scientists and medical professionals. […] Infection with drug-resistant organisms can lead to increased and longer hospital stays, more complicated treatment, more deaths, and higher healthcare costs. […] Scientists would further like to understand the genetic changes in MRSA that allow the bacterium to cause serious illness in otherwise healthy individuals.
  • #75 MRSA Surgical Site Infections: What You Should Know | bioMérieux Living Diagnostics Blog
    https://www.biomerieux.com/corp/en/blog/infectious-diseases/MRSA-surgical-site-infections.html
    In low- and middle-income countries, 11% of patients who undergo surgery are infected in the process. […] However, with antimicrobial resistance on the rise, many infections are becoming more and more difficult to treat. MRSA, or methicillin-resistant Staphylococcus aureus, is a type of S. aureus that has become resistant to many first-line antibiotics and it commonly infects surgical wounds. […] According to a recent report in The Lancet, Staphylococcus aureus is among the six leading pathogens for deaths associated with resistance. MRSA poses a serious threat to public health and safety given its association with significantly high morbidity and mortality. […] Studies show that 1 in 3 people carry S. aureus in their nose and 2 in 100 carry MRSA in their nose. […] The degree of risk for a surgical site infection is related to the type of surgery and whether an infection is present at the time of surgery.
  • #76 Methicillin-resistant Staphylococcus aureus – Wikipedia
    https://en.wikipedia.org/wiki/Methicillin-resistant_Staphylococcus_aureus
    Methicillin-resistant Staphylococcus aureus (MRSA) is a group of gram-positive bacteria that are genetically distinct from other strains of Staphylococcus aureus. MRSA is responsible for several difficult-to-treat infections in humans. It caused more than 100,000 deaths worldwide attributable to antimicrobial resistance in 2019. […] MRSA is any strain of S. aureus that has developed (through natural selection) or acquired (through horizontal gene transfer) a multiple drug resistance to beta-lactam antibiotics. […] MRSA infection is common in hospitals, prisons, and nursing homes, where people with open wounds, invasive devices such as catheters, and weakened immune systems are at greater risk of healthcare-associated infection. […] MRSA began as a hospital-acquired infection but has become community-acquired, as well as livestock-acquired.
  • #77 Methicillin-resistant Staphylococcus aureus: an overview of basic and clinical research | Nature Reviews Microbiology
    https://www.nature.com/articles/s41579-018-0147-4
    Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most successful modern pathogens. […] The same organism that lives as a commensal and is transmitted in both health-care and community settings is also a leading cause of bacteraemia, endocarditis, skin and soft tissue infections, bone and joint infections and hospital-acquired infections. […] Genetically diverse, the epidemiology of MRSA is primarily characterized by the serial emergence of epidemic strains. […] Although its incidence has recently declined in some regions, MRSA still poses a formidable clinical threat, with persistently high morbidity and mortality. […] Successful treatment remains challenging and requires the evaluation of both novel antimicrobials and adjunctive aspects of care, such as infectious disease consultation, echocardiography and source control.
  • #78 MRSA infection – Symptoms & causes – Mayo Clinic
    https://www.mayoclinic.org/diseases-conditions/mrsa/symptoms-causes/syc-20375336
    Methicillin-resistant Staphylococcus aureus (MRSA) infection is caused by a type of staph bacteria that’s become resistant to many of the antibiotics used to treat ordinary staph infections. […] Different varieties of Staphylococcus aureus bacteria, commonly called „staph,” exist. Staph bacteria are normally found on the skin or in the nose of about one-third of the population. The bacteria are generally harmless unless they enter the body through a cut or other wound, and even then they usually cause only minor skin problems in healthy people. […] According to the Centers for Disease Control and Prevention, around 5% of the population chronically carries the type of staph bacteria known as MRSA. […] MRSA is the result of decades of often unnecessary antibiotic use. For years, antibiotics have been prescribed for colds, flu and other viral infections that don’t respond to these drugs. Even when antibiotics are used appropriately, they contribute to the rise of drug-resistant bacteria because they don’t destroy every germ they target. Bacteria live on an evolutionary fast track, so germs that survive treatment with one antibiotic soon learn to resist others.
  • #79 Pathogenesis of Methicillin-Resistant Staphylococcus aureus Infection
    https://pmc.ncbi.nlm.nih.gov/articles/PMC2474459/
    Staphylococcus aureus is a versatile pathogen capable of causing a wide range of human diseases. […] Although methicillin-resistant S. aureus (MRSA) strains are not necessarily more virulent than methicillin-sensitive S. aureus strains, some MRSA strains contain factors or genetic backgrounds that may enhance their virulence or may enable them to cause particular clinical syndromes. […] Certain MRSA strains appear to contain particular factors or genetic backgrounds that enhance their virulence or enable them to cause particular clinical syndromes. […] Methicillin resistance is conferred by the mecA gene, which encodes a penicillin-binding protein (PBP2A) with decreased affinity for -lactam antibiotics. […] The basis for the apparent increased virulence of CA-MRSA strains is incompletely understood.
  • #80 Methicillin-Resistant Staphylococcus Aureus (MRSA) | BCM
    https://www.bcm.edu/departments/molecular-virology-and-microbiology/emerging-infections-and-biodefense/specific-agents/mrsa
    Drug resistance occurs because microbes, such as staph bacteria, need to reproduce to ensure their survival. […] When this ability is threatened, as when they are exposed to antibiotics, microbes adapt and evolve to overcome the block to their reproduction. […] However, drug resistance adaptations can be accelerated by human actions, particularly by the overuse and inappropriate use of antibiotics. […] The consequences of antimicrobial resistance pose a significant concern to scientists and medical professionals. […] Infection with drug-resistant organisms can lead to increased and longer hospital stays, more complicated treatment, more deaths, and higher healthcare costs. […] Scientists would further like to understand the genetic changes in MRSA that allow the bacterium to cause serious illness in otherwise healthy individuals.
  • #81 MRSA (Methicillin-resistant Staphylococcus aureus) Infection
    https://mydoctor.kaiserpermanente.org/mas/structured-content/Condition_MRSA_Methicillin_Resistant_Staphylococcus_aureus_Infection_-_Medicine.xml?co=/regions/mas
    Methicillin-resistant Staphylococcus aureus (MRSA) infection is caused by Staphylococcus aureus (staph) bacteria. MRSA is most commonly spread through contact with an infected person. […] MRSA is most commonly spread by close contact with an infected person. Bacteria can transfer to another person during skin-to-skin contact. It can also spread from infected skin to towels, soaps, and sheets. The next person using these items may pick up the bacteria. […] MRSA and similar bacteria have developed resistance to commonly used antibiotics. These antibiotics no longer effectively treat MRSA-caused infections. Though some resistance would have happened naturally, modern medicine’s over-use of antibiotics has contributed to strongly resistant bacterial strains such as MRSA.
  • #82 Pathogenesis of Methicillin-Resistant Staphylococcus aureus Infection
    https://pmc.ncbi.nlm.nih.gov/articles/PMC2474459/
    The genes and mechanisms by which CA-MRSA strains may cause aggressive disease are discussed in the sections that follow. […] There is a strong epidemiological association between PVL and the emergence of CA-MRSA infections. […] Given this evidence and the strong epidemiological association between PVL-containing CA-MRSA strains and necrotizing pneumonia and skin and soft-tissue infections, it is plausible that PVL is partly responsible for the enhanced virulence of CA-MRSA. […] The association of PVL with enhanced S. aureus virulence is complex and controversial and warrants further investigation. […] The role of many virulence factors in the pathogenesis of staphylococcal disease is unclear. […] To date, there is no compelling evidence that MRSA, in general, is more virulent than MSSA.
  • #83 Methicillin-resistant Staphylococcus aureus: an overview of basic and clinical research | Nature Reviews Microbiology
    https://www.nature.com/articles/s41579-018-0147-4
    Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most successful modern pathogens. […] The same organism that lives as a commensal and is transmitted in both health-care and community settings is also a leading cause of bacteraemia, endocarditis, skin and soft tissue infections, bone and joint infections and hospital-acquired infections. […] Genetically diverse, the epidemiology of MRSA is primarily characterized by the serial emergence of epidemic strains. […] Although its incidence has recently declined in some regions, MRSA still poses a formidable clinical threat, with persistently high morbidity and mortality. […] Successful treatment remains challenging and requires the evaluation of both novel antimicrobials and adjunctive aspects of care, such as infectious disease consultation, echocardiography and source control.

Zobacz więcej

bakteriofag VISA MRSA białko wiążące penicylinę LA-MRSA zakażenie związane z opieką zdrowotną gronkowiec złocisty gen mecA CA-MRSA czynnik zjadliwości szczep MRSA martwicze zapalenie płuc horyzontalny transfer genów HA-MRSA nadużywanie antybiotyków nosiciel MRSA metycylinooporny gronkowiec złocisty leukocydyna Panton-Valentine antybiotyk beta-laktamowy zakażenie miejsca operowanego patogen oporny na antybiotyki oporność na antybiotyki