Materiały źródłowe

• #1 Zika Virus: Causes, Symptoms, Treatment & Prevention

  https://my.clevelandclinic.org/health/diseases/16077-zika-virus

  Zika virus infections usually go away on their own. But if you’re pregnant and have Zika, it can cause congenital (present at birth) conditions in your baby, such as vision loss or improper brain development. These conditions are permanent. […] If you’re pregnant and test positive for Zika, your pregnancy care provider will monitor your health and the health of the fetus closely. When your child is born, a provider will test them for Zika-related issues. […] Remember that your provider can’t predict or prevent pregnancy complications and the congenital conditions that Zika can cause. But they can help prepare you for challenges you and your child might face when they’re born. […] If you’re pregnant and infected with Zika, the virus can also infect the fetus and interfere with its development. About 5% (1 in 20) of babies born to someone infected with Zika have congenital conditions, including: A smaller-than-average head (microcephaly). Microcephaly can mean your child’s brain didn’t develop properly.

• #2 Update: Interim Guidance for the Diagnosis, Evaluation, and Management of Infants with Possible Congenital Zika Virus Infection — United States, October 2017 | MMWR

  https://www.cdc.gov/mmwr/volumes/66/wr/mm6641a1.htm

  CDC has updated its interim guidance for U.S. health care providers caring for infants with possible congenital Zika virus infection in response to recently published updated guidance for health care providers caring for pregnant women with possible Zika virus exposure, unknown sensitivity and specificity of currently available diagnostic tests for congenital Zika virus infection, and recognition of additional clinical findings associated with congenital Zika virus infection. […] The long-term prognosis for infants with congenital Zika virus infection is not yet known; health care providers should strive to address families concerns, facilitate early identification of abnormal findings, and refer infants for neurodevelopmental follow-up and therapy when indicated.

• #3 Zika Virus: Causes, Symptoms, Treatment & Prevention

  https://my.clevelandclinic.org/health/diseases/16077-zika-virus

  Congenital Zika syndrome. This is a combination of conditions at birth, including severe microcephaly, a partially collapsed skull, a reduced amount of brain tissue, eye damage, joint issues and too much muscle tone (hypertonia). […] Improper brain development. This includes neural tube defects, an absence of folds in the brain (smooth brain or lissencephaly), hydrocephalus, missing brain structures, brain atrophy and other issues. […] Cerebral palsy. Cerebral palsy affects your coordination and ability to control your muscles. […] Vision or hearing problems. […] Low birth weight. […] Zika virus usually isn’t serious for adults and children. But if you’re pregnant and get infected, it can keep the fetus’s brain from developing properly and cause other health issues at birth. If you’re pregnant and have been diagnosed with Zika, your pregnancy care provider can guide you through what to expect in your specific situation. Although Zika can cause congenital conditions, remember that most babies born to someone with Zika don’t have Zika-related conditions.

• #4 Long-term persistence of infectious Zika virus: Inflammation and behavioral sequela in mice

  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7728251/

  The neurodevelopmental defects associated with ZIKV infections early in pregnancy are well documented, however the potential defects and long-term consequences associated with milder infections in late pregnancy and perinatal period are less well understood. […] Despite apparent recovery, MRI of convalescent mice show reduced cerebellar volume that correlates with altered coordination and motor function as well as hyperactivity and impulsivity. […] This raises concern regarding possible long-term effects in asymptomatic children exposed to the virus and suggests that long-term neurological and behavioral monitoring as well as anti-viral treatment to clear virus from the CNS may be useful in patients exposed to ZIKV at an early age. […] This suggests anti-viral treatment and long-term neurological and behavioral monitoring may be indicated for patients exposed to ZIKV early in life.

• #5 Long-term persistence of infectious Zika virus: Inflammation and behavioral sequela in mice

  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7728251/

  The infection appears to persist in defined reservoirs within CNS, the resulting inflammation could increase the risk of neurodegenerative disorders. […] These studies raise the possibility that individuals exposed to Zika early in development may not only experience long-term sequelae associated with the tissue damage that occurs during acute infection, but also have continuous foci of persistent inflammation in their CNS parenchyma that limit the spread of live replicating virus but may worsen their long-term prognosis. […] Together, these studies raise the possibility that virus may also persist in patients leading to chronic local inflammation and apoptosis. […] This suggests that the use of anti-viral drugs to completely eradicate the virus from the brain may be considered, and that anti-inflammatory or immunosuppressive therapies in patients that were infected with Zika early in life should be undertaken with caution. […] The data suggests the need to closely monitor exposed children, as an apparently transient ZIKV infection early in development could result in life-term behavioral and psychological deficits.

• #6 Predicting Efficacy of a Purified Inactivated Zika Virus Vaccine in Flavivirus-Naïve Humans Using an Immunological Correlate of Protection in Non-Human Primates

  https://www.mdpi.com/2076-2607/12/6/1177

  A traditional phase 3 clinical efficacy study for a Zika vaccine may be unfeasible because of the current low transmission of Zika virus (ZIKV). […] An alternative clinical development approach to evaluate Zika vaccine efficacy (VE) is therefore required, delineated in the US FDA’s Accelerated Approval Program for licensure, which utilizes an anti-Zika neutralizing antibody (Zika NAb) titer correlated with non-human primate (NHP) protection as a surrogate endpoint. […] We provide a statistical framework to predict the probability of protection for human participants vaccinated with a purified inactivated ZIKV vaccine (TAK-426), in the absence of VE measurements, using NHP data under a single-correlate model. […] Based on a logistic regression (LR) with bias-reduction model, a probability of 90% protection in humans is expected with a ZIKV NAb geometric mean titer (GMT) ≥ 3.38 log10 half-maximal effective concentration (EC50).

• #7 Predicting Efficacy of a Purified Inactivated Zika Virus Vaccine in Flavivirus-Naïve Humans Using an Immunological Correlate of Protection in Non-Human Primates

  https://www.mdpi.com/2076-2607/12/6/1177

  The predicted probability of protection of TAK-426 against ZIKV infection was determined using the two-parameter LR model that fit the calculated VE in rhesus macaques and the flavivirus-naïve phase 1 trial participants’ ZIKV NAb GMTs log10 EC50, measured by a ZIKV reporter virus particle assay, at 1 month post dose 2. […] The TAK-426 10 µg dose predicted a probability of protection from infection of 98% among flavivirus-naïve phase 1 trial participants. […] The use of ZIKV NAbs as a surrogate endpoint for protection against ZIKV infection is supported by (but not limited to) the following precedents: (i) NAbs specifically directed against the E protein have been identified as correlates of protection for vaccines directed against other flaviviruses (FVs), such as Japanese encephalitis virus, yellow fever virus, and tickborne encephalitis viruses.

• #8 Predicting Efficacy of a Purified Inactivated Zika Virus Vaccine in Flavivirus-Naïve Humans Using an Immunological Correlate of Protection in Non-Human Primates

  https://www.mdpi.com/2076-2607/12/6/1177

  Animal models are adequate to estimate or confirm NAb titer thresholds that correlate with protection against ZIKV infection (i.e., VE). […] The closest ZIKV infection model to humans is NHPs. […] In summary, an immunological marker is identified as a surrogate endpoint that is reasonably likely to predict clinical benefit and therefore is utilized to estimate VE. […] A major limitation faced by ZIKV vaccine developers is the lack of an immune marker of protection following ZIKV natural infection such as the one reported for chikungunya virus used for FDA licensure of IXCHIQ and recommendations following the US Food and Drug Administration’s Accelerated Approval pathway. […] Nonetheless, under the current ZIKV transmission conditions (characterized by low levels of circulation and the absence of major outbreaks), the use of TAK-426–elicited ZIKV NAbs as a surrogate of protection in the pathway for licensure is supported by published data on TAK-426 in humans and animal models and has been discussed with regulators.

• #9 A systematic review and evaluation of Zika virus forecasting and prediction research during a public health emergency of international concern

  https://pmc.ncbi.nlm.nih.gov/articles/PMC6805005/

  Epidemic forecasting and prediction tools have the potential to provide actionable information in the midst of emerging epidemics. While numerous predictive studies were published during the 2016-2017 Zika Virus (ZIKV) pandemic, it remains unknown how timely, reproducible, and actionable the information produced by these studies was. […] Many ZIKV predictions were published during the 2016-2017 pandemic. The accessibility, reproducibility, timeliness, and incorporation of uncertainty in these published predictions varied and indicates there is substantial room for improvement. To enhance the utility of analytical tools for outbreak response it is essential to improve the sharing of model data, code, and preprints for future outbreaks, epidemics, and pandemics. […] Our systematic review identified a large number of Zika models that predicted a wide range of epidemiological and ecological phenomena. The most commonly predicted phenomena were spatial spread, R0, epidemic dynamics, microcephaly burden, and vector competence. Notably few of the studies modeled the impact or cost-effectiveness of interventions, sexual transmission risk, or GBS burden.

• #10 A systematic review and evaluation of Zika virus forecasting and prediction research during a public health emergency of international concern

  https://pmc.ncbi.nlm.nih.gov/articles/PMC6805005/

  Our results also identified the need for improved sharing of computational code to permit full result reproducibility. Shared model code could also be adapted by other researchers during time-sensitive epidemics. […] Overall, the review identified several areas of improvement such as providing data and code, developing reporting standards, posting preprints, and communicating uncertainty. Addressing these areas can improve our understanding of Zika and other outbreaks and ensure that forecasts can inform preparedness and response to future outbreaks, epidemics, and pandemics.

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