Lausanne University Hospital, Switzerland
Posters & Accepted Abstracts: J Infect Dis Preve Med
There is ongoing controversy as to whether prolonged maternal viremia after Zika infection represents a risk factor for maternal-fetal transmission and subsequent adverse outcomes. In this prospective cohort study, we enrolled ZIKV-infected pregnant women with a positive polymerase chain-reaction at inclusion, and non-infected pregnant women tested by serology in each trimester and at delivery from January to July 2016. Prolonged viremia was defined as ongoing virus detection at least 30 days post infection. Adverse outcomes (fetal loss or neurologic anomalies) were more common in fetuses and neonates from mothers with prolonged viremia (6/15; 40.0%) compared to those from infected mothers without prolonged viremia (1/19; 5.3%, adjusted Relative Risk (aRR) 7.2 [95%CI 0.9-57.6]) or those from non-infected mothers (20/332; 6.6%, aRR 6.7 [95%CI 3.0-15.1]), respectively. Congenital infections were confirmed more often in fetuses and neonates from mothers with prolonged viremia compared to others (60% vs 26.3% vs 0.0%): aRR 2.3 [95%CI 0.9-5.5].