SARS-CoV-2-related mortality in a rural Latin American population

A sudden increase in adult mortality associated with respiratory diseases was noticed in Atahualpa (a rural Ecuadorian village), coinciding with the introduction of SARS-CoV-2 in the region. From a total of 1,852 individuals aged ≥18 years, 40 deaths occurred between January and June, 2020. In addition, a seroprevalence survey showed that 45% of the adult population have SARS-CoV-2 antibodies. Verbal autopsies revealed SARS-CoV-2 as the most likely cause of death in 29 cases. The mean age of suspected or confirmed SARS-CoV-2 cases was 76.9±12.1 years, while that of those dying from unrelated causes was 60.3±20.4 years (p=0.003). The overall mortality rate was 21.6 per 1,000 population (95% C.I.: 15.9 - 29.2), almost three-quarters of it due to SARS-CoV-2 (15.7 per 1,000; 95% C.I.: 11 - 22.4). This configures a 266% of excess mortality when compared to 5.9 per 1,000 (95% C.I.: 3.3 - 10.6) deaths from other causes. When SARS-CoV-2 mortality rate was calculated in individuals aged ≥60 years, it raised up to 68.9 per 1,000 (95% C.I.: 47.8 - 98.4). After peaking in April and May, mortality significantly decreased. It is possible that the high proportion of infected individuals and the resulting herd immunity contributed to the observed reduction in mortality.