Higher case fatality rate among obstetric patients with COVID-19 in the second year of pandemic in Brazil: do new genetic variants play a role?

BackgroundIn Brazil, a 20% increase in maternal mortality rate due to COVID-19 is projected for 2020. On January 4, 2021, the P.1 SARS-CoV-2 genetic variant was firstly identified in the country and recent data has indicated an association with higher hospitalization rates and mortality. The impact of P.1 variant in the obstetric population remains unclear. MethodsWe carried out a preliminary analysis of sociodemographic and clinical characteristics of COVID-19 confirmed maternal deaths (between 10-50 years old) comparing cases reported to the Brazilian official severe acute respiratory syndrome (SARS) surveillance system (SS) in 2020 with those from 2021 (until April 12, 2021). This preliminary analysis employed methods described in previous reports from our group. Results803 maternal deaths out of 8,248 COVID-19 maternal SARS cases with a recorded outcome were reported to the SARS-SS since March 2020. Case fatality rate was significantly higher in 2021 (15.6% vs 7.4%). The first three months of 2021 already account for 46.2% of all deaths occurred in the 13-months analysed period. COVID-19 fatal cases from 2021 had a lower proportion of at least one risk factor or comorbidity as compared to 2020 but had a higher frequency of obesity. There were no significant differences in terms of age, type of residence area (urban, rural, or peri-urban), type of funding of the notification unit (public vs. private), COVID-19 diagnostic criteria, pregnancy status (pregnancy or postpartum), cardiovascular disease or diabetes. The proportion of hospitalization, ICU admission, and respiratory support before death was also not significantly different. ConclusionCase fatality rate was increased in the three first months of 2021 when compared to 2020. Once variables related to health care access and demographics are not significantly different and women seem to be healthier in the 2021 sample, such difference may be related to the circulation of more aggressive genetic variants in the country.