Study Population
Every pregnant woman who contacted a health facility with Flavivirus-like symptoms and were reported to the local Disease Control Division (DCD) and had blood (within 5 days of symptoms) and urine (within 8 days) taken for RNA-ZIKV17 testing by Adolfo Lutz Institute ZIKV infection was confirmed in women if there was detectable ZIKV-RNA in blood, urine, amniotic fluid, or feto-placental tissue after pregnancy loss.
Most patients received prenatal care and delivered in various institutions without knowing their ZIKV-RNA status, as the sudden pandemic meant that demands on the single reference laboratory was very high, leading to delay in results (median 39 days). A taskforce (NATZIG study team, Ribeirão Preto DCD, and the São Paulo State Secretary of Health) contacted all mothers and obtain pregnancy, delivery, and neonatal information from medical records, their family physicians and directly from patients.