Dataset Information

Effectiveness of mRNA and inactivated COVID-19 vaccines: A test-negative study in an infection-naive Hong Kong population.

ABSTRACT:

Objective

Assess real-world effectiveness of vaccines against COVID-19.

Methods

A test-negative study was conducted in January-May 2022 during an Omicron BA.2 wave in Hong Kong. COVID-19 was identified by RT-PCR. 1-1 case-control matching was based on propensity score with vaccine effectiveness adjusted for confounders.

Results

Altogether, 1781 cases and 1737 controls aged 3-105 years were analysed. The mean lag time from the last dose of vaccination to testing for SARS-CoV-2 was 133.9 (SD: 84.4) days. Two doses of either vaccine within 180 days offered a low effectiveness against COVID-19 of all severity combined (VE_adj [95% CI] for BNT162b2: 27.0% [4.2-44.5], CoronaVac: 22.9% [1.3-39.7]), and further decreased after 180 days. Two doses of CoronaVac were poorly protective 39.5% [4.9-62.5] against severe diseases for age ≥ 60 years, but the effectiveness increased substantially after the third dose (79.1% [25.7-96.7]). Two doses of BNT162b2 protected age ≥ 60 years against severe diseases (79.3% [47.2, 93.9]); however, the uptake was not high enough to assess three doses.

Conclusions

The current real-world analysis indicates a high vaccine effectiveness of three doses of inactivated virus (CoronaVac) vaccines against Omicron variant, whereas the effectiveness of two doses is suboptimal.

SUBMITTER: Ng RWY

PROVIDER: S-EPMC10219670 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Effectiveness of mRNA and inactivated COVID-19 vaccines: A test-negative study in an infection-naïve Hong Kong population.

Ng Rita W Y RWY Sze Ryan K H RKH Chong Ka Chun KC Zhao Shi S Ling Lowell L Lui Grace G Leung Agnes S Y ASY Yeung Apple C M ACM Ho Wendy C S WCS Wong Martin C S MCS Chen Zigui Z Boon Siaw S SS Hui David S C DSC Chan Paul K S PKS

The Journal of infection 20230526 2

<h4>Objective</h4>Assess real-world effectiveness of vaccines against COVID-19.<h4>Methods</h4>A test-negative study was conducted in January-May 2022 during an Omicron BA.2 wave in Hong Kong. COVID-19 was identified by RT-PCR. 1-1 case-control matching was based on propensity score with vaccine effectiveness adjusted for confounders.<h4>Results</h4>Altogether, 1781 cases and 1737 controls aged 3-105 years were analysed. The mean lag time from the last dose of vaccination to testing for SARS-CoV ...[more]

PMID: 37245544

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