US clears mixing COVID vaccine boosters

The US Food and Drug Administration (FDA) on Wednesday authorized using a "mix and match" strategy for people who require a booster shot of a Covid vaccine after their primary series. "The FDA has determined that the known and potential benefits of the use of a single heterologous booster dose outweigh the known and potential risks of their use in eligible populations," the agency said in a statement.The Pfizer, Moderna, and Johnson & Johnson vaccines are authorized in the United States. A single dose of any of them may now be used following completion of primary vaccination with a different Covid vaccine.

According to the new decision, people who received two Moderna shots initially and are 65 or older, over 18 and at high risk for Covid, or over 18 and have high occupational exposure, may now receive a booster. All adults who received the one shot J&J vaccine more than two months ago are also eligible for a booster. Previously, only immune compromised people or people who belonged to elderly or high risk groups and had received the Pfizer vaccine initially were eligible for a boost. The data supporting the decisions come from emerging research reviewed by the FDA.

To be eligible for the third dose of the Moderna vaccine, however, individuals have to be 65 years of age and older, since the federal agency considers this section of the population at ‘high risk’ of severe infection. Alternatively, the Moderna Covid-19 booster dose may also be administered to people 18 years of age and above whose job exposes them to the novel coronavirus or if they are at high risk of infection, according to the US FDA release. The third dose of the Moderna vaccine is to be administered at least six months after eligible individuals receive their first dose of an approved Covid-19 vaccine.