In utero Zika exposure ups neurodevelopmental delay risk in early childhood

Contraction of Zika virus infection during pregnancy may put the offspring at risk of neurodevelopmental delay in early childhood, as shown in a study.

Brazil-based researchers conducted a retrospective-prospective, matched cohort study that included mother–infant pairs exposed and unexposed to Zika virus during pregnancy. They used the Brazilian health surveillance system to obtain clinical and epidemiological data from the gestational period and neonatal evaluations.

Adverse outcomes of in utero Zika virus exposure vs nonexposure, including congenital anomalies (early) and neurodevelopmental delay (long term), were assessed in children.

Results showed that compared with children in the unexposed group, those in the exposed group had a nearly threefold higher risk of adverse outcomes (incidence risk ratio [IRR], 2.7, 95 percent confidence interval [CI], 1.4–5.1). The risk of motor (IRR, 3.4; 95% CI, 1.2–9.6) and cognitive delay (IRR, 4.7; 95% CI, 1.7–13.0) was significantly higher in exposed children.

When analysis was stratified by the timing of maternal infection, children who were born to mothers who contracted Zika virus infection in the first trimester (44 percent) had at least one adverse event, with the odds of adverse outcomes being 11.2-fold greater relative to children born to mothers who contracted infection in the third trimester (odds ratio, 11.2, 95 percent CI, 3.6–35.0).