Zika Virus Induced Microcephaly in Pregnancy: Is There a Specific Prenatal Biomarker Screen Available? Review and Commentary

The recent Zika virus outbreak, which began in Brazilin 2015, has been linked to microcephaly in fetuses and newborns. The virus has spread rapidly through South, Central, and even North America; hence, it has been declared a public health emergency of international concern. Presently, a specific prenatal biomarker screen for microcephaly is not in place because the cranial defect usually appears among a cluster of neural anatomic developmental malformations of the cerebrum. Although the present prenatal screen for Down syndrome (DS) in the second trimester could be utilized as a substitute triple marker biomarker assay, the risk calculations are not specific for microcephaly. Moreover, prenatal DS testing sometimes produces a negative screen and microcephaly has previously been misdiagnosed as an anencephaly. Therefore, a modified triple test for microcephaly has been suggested for the development of a more specific prenatal screening test in the second trimester of pregnancy.