Dataset Information

Change in covid-19 risk over time following vaccination with CoronaVac: test negative case-control study.

ABSTRACT:

Objective

To estimate the change in odds of covid-19 over time following primary series completion of the inactivated whole virus vaccine CoronaVac (Sinovac Biotech) in São Paulo State, Brazil.

Design

Test negative case-control study.

Setting

Community testing for covid-19 in São Paulo State, Brazil.

Participants

Adults aged ≥18 years who were residents of São Paulo state, had received two doses of CoronaVac, did not have a laboratory confirmed SARS-CoV-2 infection before vaccination, and underwent reverse transcription polymerase chain reaction (RT-PCR) testing for SARS-CoV-2 from 17 January to 14 December 2021. Cases were matched to test negative controls by age (in 5 year bands), municipality of residence, healthcare worker status, and epidemiological week of RT-PCR test.

Main outcome measures

RT-PCR confirmed symptomatic covid-19 and associated hospital admissions and deaths. Conditional logistic regression was adjusted for sex, number of covid-19 associated comorbidities, race, and previous acute respiratory illness.

Results

From 202 741 eligible people, 52 170 cases with symptomatic covid-19 and 69 115 test negative controls with covid-19 symptoms were formed into 43 257 matched sets. Adjusted odds ratios of symptomatic covid-19 increased with time since completion of the vaccination series. The increase in odds was greater in younger people and among healthcare workers, although sensitivity analyses suggested that this was in part due to bias. In addition, the adjusted odds ratios of covid-19 related hospital admission or death significantly increased with time compared with the odds 14-41 days after series completion: from 1.25 (95% confidence interval 1.04 to 1.51) at 70-97 days up to 1.94 (1.41 to 2.67) from 182 days onwards.

Conclusions

Significant increases in the risk of moderate and severe covid-19 outcomes occurred three months after primary vaccination with CoronaVac among people aged 65 and older. These findings provide supportive evidence for the implementation of vaccine boosters in these populations who received this inactivated vaccine. Studies of waning should include analyses designed to uncover common biases.

SUBMITTER: Hitchings MDT

PROVIDER: S-EPMC9189440 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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Publications

Change in covid-19 risk over time following vaccination with CoronaVac: test negative case-control study.

Hitchings Matt D T MDT Ranzani Otavio T OT Lind Margaret L ML Dorion Murilo M D'Agostini Tatiana Lang TL de Paula Regiane Cardoso RC de Paula Olivia Ferreira Pereira OFP de Moura Villela Edlaine Faria EF Scaramuzzini Torres Mario Sergio MS de Oliveira Silvano Barbosa SB Schulz Wade W Almiron Maria M Said Rodrigo R de Oliveira Roberto Dias RD Vieira da Silva Patricia P de Araújo Wildo Navegantes WN Gorinchteyn Jean Carlo JC Dean Natalie E NE Andrews Jason R JR Cummings Derek A T DAT Ko Albert I AI Croda Julio J

BMJ (Clinical research ed.) 20220613

<h4>Objective</h4>To estimate the change in odds of covid-19 over time following primary series completion of the inactivated whole virus vaccine CoronaVac (Sinovac Biotech) in São Paulo State, Brazil.<h4>Design</h4>Test negative case-control study.<h4>Setting</h4>Community testing for covid-19 in São Paulo State, Brazil.<h4>Participants</h4>Adults aged ≥18 years who were residents of São Paulo state, had received two doses of CoronaVac, did not have a laboratory confirmed SARS-CoV-2 infection b ...[more]

PMID: 35697361

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Dataset Information

Change in covid-19 risk over time following vaccination with CoronaVac: test negative case-control study.

Objective

Design

Setting

Participants

Main outcome measures

Results

Conclusions

Publications

Change in covid-19 risk over time following vaccination with CoronaVac: test negative case-control study.

Similar Datasets

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