Vertical transmission of Zika virus and its outcomes: a Bayesian synthesis of prospective studies

02 Nov, 2020

Authors: A E Ades, Antoni Soriano-Arandes, Ana Alarcon, Francesco Bonfante, Claire Thorne, Catherine S Peckham, Carlo Giaquinto

Published in: The Lancet

Abstract
Background:  Prospective studies of Zika virus in pregnancy have reported rates of congenital Zika syndrome and other adverse outcomes by trimester. However, Zika virus can infect and damage the fetus early in utero, but clear before delivery. The true vertical transmission rate is therefore unknown. We aimed to provide the first estimates of underlying vertical transmission rates and adverse outcomes due to congenital infection with Zika virus by trimester of exposure.

Methods: This was a Bayesian latent class analysis of data from seven prospective studies of Zika virus in pregnancy. We estimated vertical transmission rates, rates of Zika-virus-related and non-Zika-virus-related adverse outcomes, and the diagnostic sensitivity of markers of congenital infection. We allowed for variation between studies in these parameters and used information from women in comparison groups with no PCR-confirmed infection, where available.

Funding: European Union Horizon 2020 programme.