UK study reveals COVID-19 vaccination effectively boosts anti-S antibody levels and reduces symptom severity post-infection, irrespective of the viral variant involved. High antibody levels are linked to quicker viral clearance, suggesting reduced transmission risk.
By Neha MathurSep 10 2023 In a recent article posted to the medRxiv* preprint server, researchers evaluated the serological outcomes of severe acute respiratory syndrome coronavirus 2 infection among coronavirus disease 2019 vaccinated and unvaccinated individuals in England during the Alpha, Delta, and Omicron waves spanning the period between February 2021 and April 2022.
Background Similar to the SARS-CoV-2 transmission pattern worldwide, in England, each variant had a distinct time of predominance; for instance, Alpha was the predominant variant before May 2021, while Delta dominated between May and November 2021. The Delta variant caused more severe infections and was highly transmissible, yet Omicron emerged and replaced Delta as the predominant variant from December 2021 onward.
However, the effect of antibody responses on the risk of developing severe COVID-19 by vaccine type, vaccination status, and infecting variant requires further investigation. This data could inform future vaccination strategies and design more effective next-generation COVID-19 vaccines for the future.
The RT-PCR cycle threshold value indicated SARS-CoV-2 viral load, and whole-genome sequencing confirmed the variant status of SARS-CoV-2-positive RT-PCR swabs. The study analysis covered data from individuals with qualitative acute or convalescent antibody results. Results The analytical set of the current study comprised 1,497 RT-PCR-positive individuals with an average age of 49 years who had different vaccination statuses and contracted infection from different SARS-CoV-2 variants.