ArticleBMC public health2023
Vaccine coverage and effectiveness against laboratory-confirmed symptomatic and severe Covid-19 in indigenous people in Brazil: a cohort study.
Article in BMC public health, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 10 papers, 1 of them a synthesis that pooled it.
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Who cites it
10 citing papers in PubMed, 1 synthesis or guideline pooled it, 14 citations in OpenAlex.
- Impact of Coronavirus Disease (COVID)-19 on the Indigenous Population of Brazil: A Systematic Review.Journal of racial and ethnic health disparities · 2026Pooled it
- Vaccination Coverage Against Coronavirus Disease 2019 (COVID-19) in Brazil's Indigenous Population.Journal of medical virology · 2026Article
- Effectiveness and feasibility of vaccination interventions for Indigenous and hard-to-reach populations in Latin America and the Caribbean: a systematic review and meta-analysis.Therapeutic advances in vaccines and immunotherapy · 2026Review
- Varicella outbreak at the Itamaraju Indigenous Health Base Center: a descriptive study, Bahia, 2024.Epidemiologia e servicos de saude : revista do Sistema Unico de Saude do Brasil · 2026Article
- Effectiveness of Sinovac vaccine against SARS-CoV-2 (CoronaVac) in reducing in-hospital mortality in individuals with COVID-19 and schizophrenia: a retrospective cohort study.BMC public health · 2025Article
- Unequal access in a universal health system: COVID-19 vaccination and health services utilization among international migrants in Brazil.BMC public health · 2025Article
- Bridging the Infodemic Equity Gap: North-South Digital Health Disparities and a Framework for Action.Journal of medical Internet research · 2025Article
- SARS-CoV-2 infection in the Indigenous Pataxó community of Southern Bahia, Brazil: second wave of transmission and vaccine effects.Cadernos de saude publica · 2025Article
- Immune Response to an Inactivated Vaccine of SARS-CoV-2 (CoronaVac) in an Indigenous Brazilian Population: A Cohort Study.Vaccines · 2024Article
- COVID-19 vaccine uptake and barriers among Indigenous language speakers in Mexico: Results from a nationally representative survey.PLOS global public health · 2024Article
Corrections and comments
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Authors and funding
13 authors at 6 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundIndigenous people have historically suffered devastating impacts from epidemics and continue to have lower access to healthcare and be especially vulnerable to respiratory infections. We estimated the coverage and effectiveness of Covid-19 vaccines against laboratory-confirmed Covid-19 cases among indigenous people in Brazil.
methodsWe linked nationwide Covid-19 vaccination data with flu-like surveillance records and studied a cohort of vaccinated indigenous people aged ≥ 5 years between 18th January 2021 and 1st March 2022. We considered individuals unexposed from the date they received the first dose of vaccine until the 13th day of vaccination, partially vaccinated from the 14th day after the first dose until the 13th day after receiving the second dose, and fully vaccinated onwards. We estimated the Covid-19 vaccination coverage and used Poisson regression to calculate the relative risks (RR) and vaccine effectiveness (VE) of CoronaVac, ChAdOx1, and BNT162b2 against Covid-19 laboratory-confirmed cases incidence, mortality, hospitalisation, and hospital-progression to Intensive Care Unit (ICU) or death. VE was estimated as (1-RR)*100, comparing unexposed to partially or fully vaccinated.
resultsBy 1st March 2022, 48.7% (35.0-62.3) of eligible indigenous people vs. 74.8% (57.9-91.8) overall Brazilians had been fully vaccinated for Covid-19. Among fully vaccinated indigenous people, we found a lower risk of symptomatic cases (RR: 0.47, 95%CI: 0.40-0.56) and mortality (RR: 0.47, 95%CI: 0.14-1.56) after the 14th day of the second dose. VE for the three Covid-19 vaccines combined was 53% (95%CI:44-60%) for symptomatic cases, 53% (95%CI:-56-86%) for mortality and 41% (95%CI:-35-75%) for hospitalisation. In our sample, we found that vaccination did not reduce Covid-19 related hospitalisation. However, among hospitalised patients, we found a lower risk of progression to ICU (RR: 0.14, 95%CI: 0.02-0.81; VE: 87%, 95%CI:27-98%) and Covid-19 death (RR: 0.04, 95%CI:0.01-0.10; VE: 96%, 95%CI: 90-99%) after the 14th day of the second dose.
conclusionsLower coverage but similar Covid-19 VE among indigenous people than overall Brazilians suggest the need to expand access, timely vaccination, and urgently offer booster doses to achieve a great level of protection among this group.
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