The 3rd dose will help anyone with a weakened immune system to have stronger protection against COVID-19. This is since they are more likely to have an infection after getting the vaccine. Studies have shown 2 doses of the COVID-19 vaccine are less effective in this people group compared to those without chronic conditions. CDC recommends an extra dose of an mRNA COVID-19 vaccine be given at least 4 weeks after a second dose of Pfizer-BioNTech COVID-19 vaccine or Moderna COVID-19 vaccine.
A “booster” may be recommended in the fall for other groups whose protection wanes or goes away over time. More information on when boosters may be needed will become available in the weeks to come following approvals and guidance from the FDA and CDC.