lancet-header

Preprints with The Lancet is part of SSRN´s First Look, a place where journals identify content of interest prior to publication. Authors have opted in at submission to The Lancet family of journals to post their preprints on Preprints with The Lancet. The usual SSRN checks and a Lancet-specific check for appropriateness and transparency have been applied. Preprints available here are not Lancet publications or necessarily under review with a Lancet journal. These preprints are early stage research papers that have not been peer-reviewed. The findings should not be used for clinical or public health decision making and should not be presented to a lay audience without highlighting that they are preliminary and have not been peer-reviewed. For more information on this collaboration, see the comments published in The Lancet about the trial period, and our decision to make this a permanent offering, or visit The Lancet´s FAQ page, and for any feedback please contact preprints@lancet.com.

Vaccine Coverage and Effectiveness Against Laboratory-Confirmed Symptomatic and Severe COVID-19 in Indigenous People in Brazil: A Cohort Study

19 Pages Posted: 20 Sep 2022

See all articles by Julia Moreira Pescarini

Julia Moreira Pescarini

Oswaldo Cruz Foundation (FIOCRUZ) - Center for Data and Knowledge Integration for Health (CIDACS)

Andrey Moreira Cardoso

Fundação Oswaldo Cruz - Escola Nacional de Saúde Pública

Ricardo Ventura Santos

Fundação Oswaldo Cruz - Escola Nacional de Saúde Pública

Priscila Scaff

Oswaldo Cruz Foundation (FIOCRUZ) - Center for Data and Knowledge Integration for Health (CIDACS)

Enny S. Paixão

Oswaldo Cruz Foundation (FIOCRUZ) - Center for Data and Knowledge Integration for Health (CIDACS)

Otávio Ranzani

Barcelona Institute for Global Health (ISGlobal)

Thiago Cerqueira-Silva

Oswaldo Cruz Foundation (FIOCRUZ) - LIB and LEITV Laboratories

Viviane Boaventura

Federal University of Bahia (UFBA)

Juracy Bertoldo Júnior

Oswaldo Cruz Foundation (FIOCRUZ) - Center for Data and Knowledge Integration for Health (CIDACS)

Vinicius de Araújo Oliveira

Oswaldo Cruz Foundation (FIOCRUZ) - Center for Data and Knowledge Integration for Health (CIDACS)

Guilherme Werneck

Universidade do Estado do Rio de Janeiro (UERJ) - Instituto de Medicina Social

Mauricio Lima Barreto

Oswaldo Cruz Foundation (FIOCRUZ) - Center for Data and Knowledge Integration for Health (CIDACS)

Manoel Barral-Netto

Oswaldo Cruz Foundation (FIOCRUZ) - Center for Data and Knowledge Integration for Health (CIDACS)

More...

Abstract

Background: We estimated the coverage and effectiveness of Covid-19 vaccines against laboratory-confirmed Covid-19 cases among indigenous people in Brazil.

Methods: We linked nationwide immunization data with symptomatic and Severe Acute Respiratory Infection records and studied a cohort of vaccinated indigenous people aged ≥5 years between 18th Jan 2021 and 1st Mar 2022. We estimated the Covid-19 vaccination coverage and used Poisson regression to calculate the vaccine effectiveness (VE) of CoronaVac, ChAdOx1, and BNT162b2 against Covid-19 laboratory-confirmed symptomatic and severe cases (i.e., mortality, hospitalisation, and hospital-progression to Intensive Care Unit (ICU) or death). VE was estimated as (1-RR)*100, comparing unexposed (<14 days after the 1st dose), to partially (≥14 days after 1st dose to <14 days after 2nd dose), or fully vaccinated (≥14 days after 2nd dose).

Findings: By 1st Mar 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 the 370,092 indigenous subjects studied, we detected 1951 Covid-19 cases, of which 105 were hospitalised and 35 died. 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. Among hospitalised patients, VE was 87% (95%CI:27-98%) for progression to ICU and 96% (95%CI: 90-99%) for death.

Interpretation: Lower coverage but similar Covid-19 vaccine effectiveness among indigenous people than overall Brazilians suggest the need to expand access, timely vaccination, especially among children and adolescents, and urgently offer booster doses to achieve a great level of protection among this group.

Funding Information: None.

Declaration of Interests: We declare no competing interests.

Ethics Approval Statement: The Brazilian National Commission on Research Ethics (CONEP) approved this study (n. 4.921.308). The study used an anonymised secondary dataset, which complies with the Brazilian General Personal Data Protection Law (LGPD).

Keywords: COVID-19, pandemic, Vaccine effectiveness, Vaccine coverage, Cohort study, Indigenous Peoples, Health services, indigenous, Indigenous population, Health of indigenous people, Amerinds, Indians, South American, Vulnerable groups, Infectious Disease Transmission, Brazil.

Suggested Citation

Pescarini, Julia Moreira and Cardoso, Andrey Moreira and Santos, Ricardo Ventura and Scaff, Priscila and Paixão, Enny S. and Ranzani, Otávio and Cerqueira-Silva, Thiago and Boaventura, Viviane and Júnior, Juracy Bertoldo and de Araújo Oliveira, Vinicius and Werneck, Guilherme and Lima Barreto, Mauricio and Barral-Netto, Manoel, Vaccine Coverage and Effectiveness Against Laboratory-Confirmed Symptomatic and Severe COVID-19 in Indigenous People in Brazil: A Cohort Study. Available at SSRN: https://ssrn.com/abstract=4224510 or http://dx.doi.org/10.2139/ssrn.4224510

Julia Moreira Pescarini

Oswaldo Cruz Foundation (FIOCRUZ) - Center for Data and Knowledge Integration for Health (CIDACS) ( email )

Bahia
Brazil

Andrey Moreira Cardoso (Contact Author)

Fundação Oswaldo Cruz - Escola Nacional de Saúde Pública ( email )

Ricardo Ventura Santos

Fundação Oswaldo Cruz - Escola Nacional de Saúde Pública ( email )

Priscila Scaff

Oswaldo Cruz Foundation (FIOCRUZ) - Center for Data and Knowledge Integration for Health (CIDACS) ( email )

Enny S. Paixão

Oswaldo Cruz Foundation (FIOCRUZ) - Center for Data and Knowledge Integration for Health (CIDACS)

Bahia
Brazil

Otávio Ranzani

Barcelona Institute for Global Health (ISGlobal) ( email )

Thiago Cerqueira-Silva

Oswaldo Cruz Foundation (FIOCRUZ) - LIB and LEITV Laboratories ( email )

Bahia
Brazil

Viviane Boaventura

Federal University of Bahia (UFBA) ( email )

Av. Reitor Miguel Calmon, s/n
Vale do Canela
Salvador, Bahia
Brazil

Juracy Bertoldo Júnior

Oswaldo Cruz Foundation (FIOCRUZ) - Center for Data and Knowledge Integration for Health (CIDACS) ( email )

Bahia
Brazil

Vinicius De Araújo Oliveira

Oswaldo Cruz Foundation (FIOCRUZ) - Center for Data and Knowledge Integration for Health (CIDACS) ( email )

Bahia
Brazil

Guilherme Werneck

Universidade do Estado do Rio de Janeiro (UERJ) - Instituto de Medicina Social ( email )

Rua São Francisco Xavier, 524
Maracanã
Rio de Janeiro, RJ
Brazil

Mauricio Lima Barreto

Oswaldo Cruz Foundation (FIOCRUZ) - Center for Data and Knowledge Integration for Health (CIDACS) ( email )

Bahia
Brazil

Manoel Barral-Netto

Oswaldo Cruz Foundation (FIOCRUZ) - Center for Data and Knowledge Integration for Health (CIDACS) ( email )

Bahia
Brazil

Click here to go to TheLancet.com

Paper statistics

Downloads
192
Abstract Views
681
PlumX Metrics