Emerging Role of Zika Virus in Adverse Fetal and Neonatal Outcomes

Abstract

SUMMARYThe rapid spread of the Zika virus (ZIKV) in the Americas and its potential association with thousands of suspected cases of microcephaly in Brazil and higher rates of Guillain-Barré syndrome meet the conditions for a Public Health Emergency of International Concern, as stated by the World Health Organization in February 2016. Two months later, the Centers for Disease Control and Prevention (CDC) announced that the current available evidence supports the existence of a causal relationship between prenatal Zika virus infection and microcephaly and other serious brain anomalies. Microcephaly can be caused by several factors, and its clinical course and prognosis are difficult to predict. Other pathogens with proven teratogenicity have been identified long before the current ZIKV epidemic. Despite the growing number of cases with maternal signs of infection and/or presence of ZIKV in tissues of affected newborns or fetuses, it is currently difficult to assess the magnitude of increase of microcephaly prevalence in Brazil, as well as the role of other factors in the development of congenital neurological conditions. Meanwhile, health agencies and medical organizations have issued cautious guidelines advising health care practitioners and expectant couples traveling to, returning from, or living in affected areas. Analogous to dengue virus (DENV) epidemics, ZIKV has the potential to become endemic in all countries infested byAedesmosquitoes, while new mutations could impact viral replication in humans, leading to increased virulence and consequently heightened chances of viral transmission to additional naive mosquito vectors. Studies are urgently needed to answer the questions surrounding ZIKV and its role in congenital neurological conditions.

Association between Zika virus infection and microcephaly in Brazil, January to May, 2016: preliminary report of a case-control study

“…The PRNT 50 assay was done using the virus strain ZIKV PE/243 isolated in Pernambuco, Brazil. Serum samples of mothers and neonates were tested for IgM and IgG antibodies specifi c for toxoplasmosis, rubella, and cytomegalovirus (the main infectious causes of congenital microcephaly 25 ).…”

Infección por virus del Zika en el embarazo, impacto fetal y neonatal

“…Esto coincide con lo reportado en la actualidad donde 75 a 80% de los pacientes infectados son asintomáticos 10 . Se podría interpretar como si el virus del Zika se hubiese quedado latente o dormido en el tiempo y ahora ha sido despertado por factores como el cambio climá-tico, el fenómeno del Niño [11][12][13][14][15] , los cuales han generado condiciones excepcionales en el Noreste de Sur América, donde en el segundo semestre de 2015, se registraron las temperaturas más calientes acompañadas de grandes sequías. Este fenómeno ha contribuido a la expansión Infectología al Día geográfica del vector, al igual que su supervivencia y replicación viral, además de incrementar la tasa de alimentación por la mosquita 16,17 .…”

Zika Virus Infection in Pregnancy, Microcephaly, and Maternal and Fetal Health: What We Think, What We Know, and What We Think We Know

“…[21][22][23][24][25] Musculoskeletal, Genitourinary, and Pulmonary Abnormalities Musculoskeletal abnormalities are frequently described in published reports of CZS, but their actual prevalence among infants of women infected during pregnancy remains unknown. Schwartz 9 analyzed 9 reported autopsies of fetuses and infants with intrauterine ZIKV infection and congenital microcephaly; of which 6 had variable findings of craniofacial malformations, craniosynostosis, and limb abnormalities, which included contractures of multiple joints or arthrogryposis.…”