According to a recent study that compares the length of immunity to SARS-CoV-2 between vaccination and spontaneous infection based on declining antibody levels, it is clear that booster vaccinations are necessary to prevent reinfections and breakthrough infections. (Also read: Free Covid booster dosages for all adults for the following 75 days at government clinics starting on July 15)
Understanding the longevity of immunity provided by vaccinations and spontaneous infection, the best time for boosters, and the possibility of breakthrough infections are necessary for the public health response to ongoing SARS-CoV-2 outbreaks.
Jeffrey P. Townsend and colleagues used comparative evolutionary analysis in a study that was published in the "Proceedings of the National Academy of Sciences" (PNAS) on June 15 to assess the longevity of immunity and chance of breakthrough infections across time.