COVID-19 vaccine coverage is lower among indigenous populations in Brazil

Inequalities in COVID-19 vaccination coverage between indigenous and non-indigenous populations were estimated in a study conducted by researchers from the Center for Data and Knowledge Integration for Health (Cidacs/Fiocruz Bahia), together with the London School of Hygiene and Tropical Medicine, the Federal University of Rio de Janeiro (UFRJ), the University of São Paulo (USP), the Universitat Pompeu Fabra (Barcelona), the Federal University of Bahia (UFBA) and the State University of Rio de Janeiro (UERJ). According to the preprint article, it is estimated that the indigenous population has a smaller proportion of people with a complete vaccination schedule, 48.7%, than non-indigenous people, 74.8%.

The study linked national data on immunization with records of symptomatic cases and Severe Acute Respiratory Infection and studied a cohort of vaccinated indigenous people over 5 years old between January 18, 2021 and March 1, 2022. Estimates of vaccine coverage were made to calculate the effectiveness of the CoronaVac, AstraZeneca (ChAdOx-1), and Pfizer (BNT162b2) vaccines.

Results point to an unequal coverage of COVID-19 vaccines between indigenous and non-indigenous people, especially among children and adolescents and regions with a greater number of indigenous people. However, the study also showed a similarity when it comes to the effectiveness of the vaccines between the two groups. Vaccine effectiveness was measured in terms of symptomatic cases, mortality and hospitalization.

The researchers recommend expanding access, especially among children and adolescents, and offering booster doses for an adequate level of protection for the indigenous group.