The following is a summary of “SARS-CoV-2 vaccine breakthrough infection in the older adults: a meta-analysis and systematic review,” published in the September 2023 issue of Infectious Disease by Jing et al.
The efficacy of the Corona Virus Disease 2019 (COVID-19) mRNA vaccine effectiveness (VE) has recently waned, with a concurrent rise in reports of COVID-19 breakthrough infection. Researchers performed a retrospective study to compare population-based studies on the prevalence and incidence of SARS-CoV-2 breakthrough infection in older adults worldwide.
They conducted a systematic review of 30 studies published in English from PubMed, Embase, Cochrane Library, and Web of Science, spanning from inception to November 2, 2022. A random-effects model was used to calculate pooled estimates of the prevalence and incidence of SARS-CoV-2 breakthrough infection in older adults. To ensure result robustness, publication bias was assessed with funnel plots, Egger’s regression test, and sensitivity analyses. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were implied.
The results showed that in this meta-analysis, 30 publications were included (17 on prevalence, 17 on incidence, and 4 on both). The pooled prevalence of COVID-19 breakthrough infection among older adults was 7.7 per 1,000 persons (95%CI] 4.0–15.0), while the pooled incidence was 29.1 per 1000 person-years (95%CI 15.2–55.7).
They concluded that the prevalence and incidence of SARS-CoV-19 breakthrough infection in older adults was low, and the risk of hospitalization, severe disease, and death was even lower.