Unequal burden of Zika-associated microcephaly among populations with public and private healthcare in Salvador, Brazil

OBJECTIVES: To describe the differences in clinical presentation and relative disease burden of congenital Zika syndrome (CZS)-associated microcephaly at 2 large hospitals in Salvador, Brazil that serve patients of different socioeconomic status (SES). METHODS: Clinical and serologic data were collected prospectively from pregnant women and their infants, who delivered at 2 study centers during the 2015–2016 Zika virus (ZIKV) epidemic in Salvador, Brazil. RESULTS: Pregnant women from Salvador, Brazil delivering in a low SES hospital had 3 times higher ZIKV exposure rate than women at a high SES hospital. However, different SES hospitals had similar prevalence of infants with CZS-associated microcephaly (10% vs 6%, p = 0.16) after controlling for ZIKV exposure in their mothers. CONCLUSIONS: Our study supports the positive association between low SES, high maternal ZIKV exposure, and high rates of CZS-associated microcephaly.