Socioecology and Prevalence of SARS-CoV-2 Infection in Quilombolas Living in the Brazilian Amazon

This cross-sectional study presents socioecological, epidemiological aspects, and the seroprevalence of immunoglobulin G (IgG) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in a group of quilombola (afro-derived) communities in the states of Pará and Tocantins, in the Brazilian Amazon, to evaluate the impact of SARS-CoV-2 prevalence among them.

A total of 551 individuals participated. The detection of anti-SARS-CoV-2 antibodies was performed using an enzyme immunoassay. Socioeconomic and ecological data was collected from all participants 7 years of age or older who were not previously vaccinated.

The seroprevalence of antibodies in both states was 40.7% and was associated with factors such as age group, contact with infected individuals, and being in lockdown inside the quilombos. In Pará, a statistically significant association was observed between seroprevalence and females, and the age group of 12-18 years. In addition, seroprevalence in Pará was higher than in Tocantins, and the reported use of masks was a protective factor, while in Tocantins, the reported use of masks was associated with the presence of antibodies. There was no association between the prevalence of antibodies and the presence of COVID-19 symptoms in Pará. However, in Tocantins, diarrhea and loss of taste were associated with infection.

Quilombola are highly vulnerable groups due to the long history of enslavement in Brazil. This is the first investigation of SARS-CoV-2 seroprevalence and its impact in these groups in the Amazon. The study helps us to understand the relationship of socioecological differences, behavioral characteristics, and the dynamics of viral transmission associated with the risk of infection by SARS-CoV-2 among traditional populations, and can be useful to the planning of more culturally adequate public health policies for future epidemics.