Infection by SARS-CoV-2 with alternate frequencies of mRNA vaccine boosting.

One of the most consequential unknowns of the COVID-19 pandemic is the frequency at which vaccine boosting provides sufficient protection from infection. We quantified the statistical likelihood of breakthrough infections over time following different boosting schedules with mRNA-1273 (Moderna) and BNT162b2 (Pfizer-BioNTech) by integration of anti-Spike IgG antibody optical densities with profiles of the waning of antibodies and corresponding probabilities of infection associated with endemic transmission. Projecting antibody levels over time given boosting every 6 months, 1 year, 1.5 years, 2 years, or 3 years yielded respective probabilities of fending off infection over a 6-year span of >93%, 75%, 55%, 40%, and 24% (mRNA-1273) and >89%, 69%, 49%, 36%, and 23% (BNT162b2). Delaying administration of boosters has bleak repercussions regarding the probability of individual infection by SARS-CoV-2, and correspondingly, to the course of ongoing disease spread, prevalence, morbidity, hospitalization, and mortality. Instituting regular, population-wide booster vaccination updated to predominant variants has the potential to substantially forestall-and with widespread uptake, eliminate-COVID-19. This article is protected by copyright. All rights reserved.