Possible Congenital Zika Syndrome in Older Children Due to Earlier Circulation of Zika Virus

Congenital Zika syndrome (CZS) was identified following a large Zika virus (ZIKV) outbreak in Brazil in 2015. Two children with clinical presentations consistent with CZS, ages 7 and 8 years old, are described. Both mothers lived in Cambodia, a region with known ZIKV, during their pregnancies and reported fever and rash in the second trimester. The infants were born with severe microcephaly. Testing for congenital infection at birth and genetic testing were unremarkable. In 2017, serologic testing for both mothers were consistent with prior ZIKV infection. Review of infant neuroimaging demonstrated ventriculomegaly, severe cerebral atrophy, and subcortical calcifications consistent with CZS. Given the maternal symptoms suggesting ZIKV infection during pregnancy and the combination of clinical and radiological features unique to CZS, CZS is strongly suspected in these children, suggesting that CZS occurred before the 2013-2014 French Polynesia outbreak. As such, CZS should be considered in older children with congenital microcephaly of unknown etiology and a history consistent with possible ZIKV exposure.