Perinatal Case Fatality Rate Related to Congenital Zika Syndrome in Brazil: a Cross-Sectional Study

BACKGROUND: Many studies have demonstrated a causal link between Zika virus (ZIKV) infection, microcephaly (MCP), and other congenital abnormalities (CA). This study aimed to determine perinatal case fatality rate in cases of Congenital Zika Syndrome (CZS) in the Rio Grande do Norte State (RN), a Brazilian Northeast State highly impacted by the Zika virus outbreak. METHODS: A cross-sectional study was conducted using data obtained through the State Health Department (SHD) for cases of MCP and CA in Rio Grande do Norte from April 2015 to February 5, 2016. Definition of perinatal period: commences at 22 completed weeks (154 days) of gestation and ends seven completed days after birth. RESULTS: During the study period, there were 486 cases of MCP and others CA notified in RN, of which 142 were confirmed and 108 remain under investigation. The remaining 236 cases have been ruled out by presenting normal examinations or due to presenting microcephaly by noninfectious causes. Of the total confirmed cases, 26.7% (38/142) died after birth or during pregnancy. 15.78% (06/38) of confirmed deaths had ZIKV infection during pregnancy and 2.63% (01/38) had a positive TORCH blood test. The six cases related to ZIKV were confirmed by RT–PCR and/or IgM/IgG antibodies against ZIKV. The remaining cases of deaths remain either under investigation or have been ruled out. CONCLUSION: This study highlights a high rate of perinatal lethality (15.78%) in cases of CZS. Despite the growing number of CZS cases, the real incidence and prevalence might be higher due to the underreporting and lack of resources for confirmatory diagnostic tests (laboratory and imaging). Due to the high rate of lethality and the ongoing uncontrolled ZIKV outbreak, this study predicts an increase in the infant mortality rate in Brazil and highlights the need for developing public health programs to control the ZIKV outbreak. DISCLOSURES: All authors: No reported disclosures.