Serologic surveillance of maternal Zika infection in a prospective cohort in Leon, Nicaragua during the peak of the Zika epidemic

• Authors: Matthew Collins, Emory University; Omar Zepeda, National Autonomous University of Nicaragua; Bryan Blette, University of North Carolina; Ramesh Jadi, University of North Carolina; Marlen Morales, National Autonomous University of Nicaragua; Rigoberto Perez, National Autonomous University of Nicaragua; Guei-Jiun Liou, University of North Carolina; Magelda Montoya-Cruz, University of California Berkeley; Eva Harris, University of California Berkeley; Sylvia Becker-Dreps, University of North Carolina; Aravinda M. de Silva, University of North Carolina; Jeffrey Stringer, University of North Carolina; Filemon Bucardo, National Autonomous University of Nicaragua; Elizabeth Stringer, University of North Carolina
• Journal Title: PLoS ONE
• Volume: Volume 15, Number 4
• Publisher: Public Library Science | 2020-04-03, Pages e0230692-e0230692
• Type of Work: Article | Final Publisher PDF
• Publisher DOI: http://doi.org/10.1371/journal.pone.0230692
• Subjects: Biology, Virology; Health Sciences, Epidemiology; Biology, Microbiology; Health Sciences, Immunology
• Keywords: Science & Technology; Multidisciplinary Sciences; Science & Technology - Other Topics; Virus; Brazil; Antibodies

Abstract

Background Zika virus caused thousands of congenital anomalies during a recent epidemic. Because Zika emerged in areas endemic for dengue and these related flaviviruses elicit cross-reactive antibodies, it is challenging to serologically monitor pregnant women for Zika infection. Methods A prospective cohort of 253 pregnant women was established in León, Nicaragua. Women were followed during prenatal care through delivery. Serologic specimens were obtained at each visit, and birth outcome was recorded. Established flavivirus serologic methods were adapted to determine Zika seroprevalence, and a stepwise testing algorithm estimated timing of Zika infection in relation to pregnancy. Results Zika seroprevalence was approximately 59% among women tested. Neutralization testing was highly concordant with Zika NS1 BOB results. Per study algorithm, 21% (40/187) of women were classified as experiencing Incident ZIKV infection during pregnancy. Importantly, the Incident ZIKV group included mostly women pregnant during the 2016 Zika epidemic peak and the only 3 subjects in the cohort with RT-PCR-confirmed infections. Approximately 17% of births had complications; 1.5% (3/194) manifesting clinical criteria of congenital Zika syndrome, one was RT-PCR-confirmed as a case of congenital Zika syndrome. Adverse birth outcome did not correlate with timing of Zika infection. Conclusions By leveraging prenatal care systems, we developed a simple algorithm for identifying women who were likely infected by Zika during pregnancy.