CDC Expands Booster Eligibility and Allows Vaccine Mix and Matching

Centers for Disease Control (CDC) director Rochelle P. Walensky, M.D., M.P.H., has recommended COVID vaccine booster shots from both Moderna and Johnson & Johnson, as well as backed mixing vaccines for the booster dose. This decision came after a unanimous recommendation from the panel of experts advising the CDC.

Experts recommend that people should aim to receive the same dose they were given originally, but if it is not possible, switching brands is an option based on availability. A preprint study from researchers at the National Institutes of Health examined mixed doses and came to the conclusion that all vaccine combinations were the same and immunogenic. Johnson & Johnson recipients were also shown to have a stronger immune response if they received a dose of one of the mRNA vaccine options over getting the Johnson & Johnson booster dose.

Dr. Walensky’s statement is as follows: “These recommendations are another example of our fundamental commitment to protect as many people as possible from COVID-19. The evidence shows that all three COVID-19 vaccines authorized in the United States are safe – as demonstrated by the over 400 million vaccine doses already given. And, they are all highly effective in reducing the risk of severe disease, hospitalization, and death, even in the midst of the widely circulating Delta variant.”

The recommendations for those who received Moderna are for everyone aged over 65 and individuals over 18 who have risk factors that predispose them to severe COVID-19 cases. Those who are at occupational risks, including frontline workers such as hospital staff, long-term care centers, teachers, mass transit employees, supermarket staff, and first responders are also included. These recommendations line up with Pfizer’s recommendation. Both doses should be given at least 6 months after completion of the 2-dose series. 

Johnson & Johnson on the other hand, has much broader recommendations. Their booster dose recommendation is eligible for anyone 18 or older after two months. Those who were originally vaccinated with Johnson & Johnson are also able to choose to get a booster with Pfizer or Moderna during the two month period and do not have to wait 6 months. 

The rare bouts of myocarditis reported by recipients of Pfizer and Moderna, which were shown to be mild and with a prompt resolution, were found to be higher in those who received Moderna than Pfizer. However, the Moderna booster will be administered as a half dose (the full dose is associated with the heart condition).

The FDA and CDC are expected to continue working on clearance for Pfizer vaccines for children ages 5-11 years old as well as deciding whether to reduce the booster age to 40 years old.