Zika Virus Infection with Prolonged Maternal Viremia and Fetal Brain Abnormalities

TLDR

The Zika virus outbreak has been linked to an increased risk of congenital microcephaly. This case report describes a pregnant woman and her fetus infected with ZIKV at 11 weeks gestation. The fetus showed progressive head‑circumference reduction, extensive brain abnormalities on ultrasound and MRI at 19–20 weeks, cortical thinning and high viral loads on postmortem examination, and maternal serum remained viremic at 16 and 21 weeks, yet no microcephaly or intracranial calcifications were observed.

Abstract

The current outbreak of Zika virus (ZIKV) infection has been associated with an apparent increased risk of congenital microcephaly. We describe a case of a pregnant woman and her fetus infected with ZIKV during the 11th gestational week. The fetal head circumference decreased from the 47th percentile to the 24th percentile between 16 and 20 weeks of gestation. ZIKV RNA was identified in maternal serum at 16 and 21 weeks of gestation. At 19 and 20 weeks of gestation, substantial brain abnormalities were detected on ultrasonography and magnetic resonance imaging (MRI) without the presence of microcephaly or intracranial calcifications. On postmortem analysis of the fetal brain, diffuse cerebral cortical thinning, high ZIKV RNA loads, and viral particles were detected, and ZIKV was subsequently isolated.