The FDA issued emergency use authorizations for all currently available COVID-19 vaccines – Pfizer, Moderna, Johnson & Johnson – allowing all adults aged 18 and older to receive a booster dose. Individuals must complete their initial vaccine series prior to receiving a booster dose, with those who received either the Pfizer or Moderna vaccine required to wait six months after completion of vaccination, and those who received the Johnson & Johnson vaccine to wait two months after completion of vaccination.