Effectiveness of the CoronaVac vaccine in the elderly population during a P.1 variant-associated epidemic of COVID-19 in Brazil: A test-negative case-control study

  title={Effectiveness of the CoronaVac vaccine in the elderly population during a P.1 variant-associated epidemic of COVID-19 in Brazil: A test-negative case-control study},
  author={Otavio Tavares Ranzani and Matthew D. Hitchings and Murilo Dorion and T. D’agostini and Regiane Cardoso de Paula and Olivia Ferreira Pereira de Paula and Edlaine Faria de Moura Villela and Mario Sergio Scaramuzzini Torres and Silvano Barbosa de Oliveira and Wade L. Schulz and Maria Almiron and R. F. C. Said and Roberto Dias de Oliveira and Patricia Vieira da Silva and Wildo Navegantes de Ara{\'u}jo and Jean Carlo Gorinchteyn and Jason R. Andrews and Derek A. T. Cummings and Albert I. Ko and Julio Croda},
Background Mass vaccination is being used in response to coronavirus disease (COVID-19) epidemics, including those driven by emerging variants of concern. We evaluated the effectiveness of the inactivated whole-virus vaccine, CoronaVac, against symptomatic COVID-19 in the elderly population of Sao Paulo State, Brazil during widespread circulation of the P.1 variant. Methods We conducted a test-negative, case-control study of adults >=70 years of age from Sao Paulo State from January 17 to April… 

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Administration of at least one dose of CoronaVac showed effectiveness against symptomatic SARS-CoV-2 infection in the setting of epidemic P.1 transmission, underscoring the need to increase vaccination efforts in response to the spread of this variant in Brazil and globally.

Prevention of Coronavirus Disease 2019 (COVID-19) by mRNA-Based Vaccines Within the General Population of California

  • K. AndrejkoJ. Pry A. Lam
  • Medicine
    Clinical infectious diseases : an official publication of the Infectious Diseases Society of America
  • 2021
Authorized mRNA-based vaccines are effective at reducing documented SARS-CoV-2 infections within the general population of California and through the matched odds ratio of prior vaccination, comparing cases with controls.

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