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Protective effectiveness of previous infection against subsequent SARS-Cov-2 infection: systematic review and meta-analysis.
- Source :
-
Frontiers in public health [Front Public Health] 2024 Jun 20; Vol. 12, pp. 1353415. Date of Electronic Publication: 2024 Jun 20 (Print Publication: 2024). - Publication Year :
- 2024
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Abstract
- Background: The protective effectiveness provided by naturally acquired immunity against SARS-CoV-2 reinfection remain controversial.<br />Objective: To systematically evaluate the protective effect of natural immunity against subsequent SARS-CoV-2 infection with different variants.<br />Methods: We searched for related studies published in seven databases before March 5, 2023. Eligible studies included in the analysis reported the risk of subsequent infection for groups with or without a prior SARS-CoV-2 infection. The primary outcome was the overall pooled incidence rate ratio ( IRR ) of SARS-CoV-2 reinfection/infection between the two groups. We also focused on the protective effectiveness of natural immunity against reinfection/infection with different SARS-CoV-2 variants. We used a random-effects model to pool the data, and obtained the bias-adjusted results using the trim-and-fill method. Meta-regression and subgroup analyses were conducted to explore the sources of heterogeneity. Sensitivity analysis was performed by excluding included studies one by one to evaluate the stability of the results.<br />Results: We identified 40 eligible articles including more than 20 million individuals without the history of SARS-CoV-2 vaccination. The bias-adjusted efficacy of naturally acquired antibodies against reinfection was estimated at 65% (pooled IRR = 0.35, 95% CI = 0.26-0.47), with higher efficacy against symptomatic COVID-19 cases (pooled IRR = 0.15, 95% CI = 0.08-0.26) than asymptomatic infection (pooled IRR = 0.40, 95% CI = 0.29-0.54). Meta-regression revealed that SARS-CoV-2 variant was a statistically significant effect modifier, which explaining 46.40% of the variation in IRR s. For different SARS-CoV-2 variant, the pooled IRRs for the Alpha (pooled IRR = 0.11, 95% CI = 0.06-0.19), Delta (pooled IRR = 0.19, 95% CI = 0.15-0.24) and Omicron (pooled IRR = 0.61, 95% CI = 0.42-0.87) variant were higher and higher. In other subgroup analyses, the pooled IRR s of SARS-CoV-2 infection were statistically various in different countries, publication year and the inclusion end time of population, with a significant difference ( p = 0.02, p < 0.010 and p < 0.010), respectively. The risk of subsequent infection in the seropositive population appeared to increase slowly over time. Despite the heterogeneity in included studies, sensitivity analyses showed stable results.<br />Conclusion: Previous SARS-CoV-2 infection provides protection against pre-omicron reinfection, but less against omicron. Ongoing viral mutation requires attention and prevention strategies, such as vaccine catch-up, in conjunction with multiple factors.<br />Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.<br /> (Copyright © 2024 Hu, Cai, Yan, Wang, Sun, Wei and Hao.)
Details
- Language :
- English
- ISSN :
- 2296-2565
- Volume :
- 12
- Database :
- MEDLINE
- Journal :
- Frontiers in public health
- Publication Type :
- Academic Journal
- Accession number :
- 38966699
- Full Text :
- https://doi.org/10.3389/fpubh.2024.1353415