Yes. The protection COVID-19 vaccines provide decreases over time, especially for certain groups of people. Recent data suggest their effectiveness at preventing infection or severe illness wanes over time, especially in people ages 65 years and older. The emergence of the variants further emphasizes the importance of vaccination, boosters, and prevention efforts needed to protect against COVID-19. CDC recommends everyone ages 12 and older get a booster for the best protection against COVID-19. Data show that an mRNA booster increases the immune response, which improves protection against getting a serious COVID-19 infection. Learn more about COVID-19 vaccine recommendations, including recommendations for people who are moderately or severely immunocompromised.