<p>Infections of the BA.3.2 variant of the COVID-causing coronavirus are still at very low levels, but experts are concerned it may be resistant to immunity from vaccines or prior infection</p>
Vaccine efficacy refers to the ability of a vaccine to prevent disease in controlled clinical trials. It is a crucial measure for understanding how well a vaccine works against specific pathogens and can vary based on factors such as the population studied and the presence of variants.
COVID-19 variants are different strains of the virus that causes COVID-19, which may arise due to mutations in the virus's genetic material. Some variants can exhibit changes in transmissibility, severity of disease, or resistance to vaccines and treatments.