Andres Moreira-Soto, Manoel Sarno, Celia Pedroso, Eduardo Martins Netto, Alexandra Rockstroh, Estela Luz, Marie Feldmann, Carlo Fischer, Fernanda Anjos Bastos, Beate M Kümmerer, Xavier de Lamballerie, Christian Drosten, Sebastian Ulbert, Carlos Brites, Jan Felix Drexler
Reliable diagnosis of congenital Zika virus (ZIKV) infection is challenging. Here, we assessed ZIKV-specific neutralizing antibodies in 28 mothers of microcephaly cases and 122 controls from north-eastern Brazil using plaque-reduction neutralization tests. ZIKV-specific antibody titers were significantly higher in cases than in controls (t-test, p<0.0001). We identified a putative case of congenital Zika syndrome retrospectively by unusually high ZIKV-specific antibody titers. High ZIKV-specific antibody titers in cases were unrelated to prior dengue virus infection. Our data suggest a strong immunological stimulus from prolonged placental or transplacental ZIKV shedding and potential utility of maternal antibody titers to corroborate congenital ZIKV infection.