SARS-CoV-2 infection after COVID-19 vaccinations among vaccinated individuals, prevention rate of COVID-19 vaccination: A systematic review and meta-analysis

Background: The global concern regarding protection against the COVID-19 variants through preexisting antibodies from vaccination or previous infection is evident. Reports from around the world indicate that a considerable number of healthcare professionals/individuals experience reinfection despite being vaccinated. Moreover, several studies have highlighted cases of symptomatic SARS-CoV-2 re -infection, specifically among individuals who have been vaccinated. Understanding the factors that contribute to these re -infections is crucial for implementing effective public health measures and enhancing vaccination strategies. Method: A comprehensive search was conducted between January 1, 2021, and February 14, 2024, using various reputable sources such as PubMed, Google scholar, Medline, EMBASE, CINAHL, and others. The search aimed to retrieve relevant research on topics related to "world nations" and phrases like "COVID-19 vaccination breakthrough infection," "SARS re -infection after COVID-19 vaccination," "COVID-19 vaccine complication," "post COVID-19 vaccination symptoms," and specific nation names. The data obtained from the databases underwent extraction and quality assessment using the Newcastle -Ottawa Scale (NOS) and the Preferred Reporting Items for Systematic Review and Meta -Analyses. Data analysis was performed using STATA 17 MP software, and measures such as the I 2 test statistic and Egger's test were used to assess heterogeneity and publication bias. The findings were presented using forest plots, displaying the odds ratio (OR) and 95 % confidence interval (CI). Result: This review and meta -analysis comprised a total of 15 articles, or a total sample size of 342,598. The pooled prevalence of SARS-CoV-2 after vaccination of COVID-19 was 9 % (95CI 7%-11 %) of population globally. This implied that reduced the overall attack rate of COVID-19 by 91 % after vaccination. The highest pooled estimated of SARS-CoV-2 infection after COVID -19 Vaccinations was seen among developing nations, 20 % (95 % CI: 5%-36 %).The pooled odds ratio showed that a significant association was found between SARS-CoV-2 infection after COVID19 vaccination and older age (OR = 2.04; 95%CI: 1.10-2.98) and comorbidity (OR = 3.25; 95% CI: 1.04-5.47). Conclusion: It is important for policymakers to prioritize continuous monitoring and surveillance of SARS-CoV-2 infection rates among vaccinated individuals globally, as there is a significant estimate of the combined prevalence of post-COVID-19 vaccine SARS-CoV-2 infections.