Some experts are calling for people who were vaccinated with Johnson & Johnson's COVID-19 vaccine to get a booster shot of an mRNA vaccine from either Pfizer or Moderna to protect against the delta variant of the coronavirus, Politico reported June 29.
Johnson & Johnson's shot had an overall efficacy rate of 72 percent in U.S. clinical trials, while both Moderna and Pfizer's had efficacy rates of up to 95 percent.
The delta variant of the coronavirus is gaining a foothold in some parts of the U.S., underscoring the need to continue vaccinations. In the week ending June 12, the delta variant accounted for nearly half of all variants sequenced in Los Angeles, nearly all cases in people who were unvaccinated.
Leena Wen, MD, an emergency physician and public health professor at George Washington University in Washington, D.C., told Politico: "Scientifically, it would make sense that getting a second dose of an mRNA vaccine could boost the immune response for those who got the one-dose J&J vaccine."
The FDA and CDC have said they don't have enough information about an mRNA booster to recommend it, Politico reported.
But early results of a British study released June 28 suggest mixing brands of COVID-19 vaccines can create strong protection against the virus.