Anthony Fauci, M.D., said that some people will very likely need a COVID-19 vaccine booster shot—but not everyone. Dr. Fauci, director of the National Institute of Allergy and Infectious Diseases, explained in a new interview that immunocompromised individuals will need additional shots of the COVID-19 vaccine in order to be adequately protected against the novel coronavirus.
“No vaccine, at least not within this category, is going to have an indefinite amount of protection,” Dr. Fauci said NBC’s Today on Thursday. “Inevitably, there will be a time when we’ll have to give boosts.” Based on the current evidence, however, public health officials are ready to recommend a booster shot—a third dose of the two-dose mRNA vaccines from Moderna or Pfizer intended to help bolster the immune system response—only to people who have compromised immune systems.
Dr. Fauci said that presently, scientists at the Centers for Disease Control and Prevention (CDC) “do not feel that we absolutely have to give [booster shots], except for the immunocompromised,” who are “imminently” going to be able to get those shots. The U.S. Food and Drug Administration (FDA) is expected to give authorization for booster shots for some immunocompromised people as soon as this week, CNN reports.
People who are immunocompromised have an immune system that is too weakened to produce an adequate protective immune response from the original vaccination. People may develop a compromised immune system due to certain conditions (such as specific genetic disorders or AIDS), an organ transplant, or certain medications (like anticancer drugs), according to the National Cancer Institute.
For this population, a booster shot could help rev up that inadequate initial immune response. In immunocompromised individuals, “who really never really got a good response to begin with,” booster shots could help them achieve the level of immunity other people got from the original vaccination, Dr. Fauci explained. (While achieving herd immunity could in theory help protect this population, vaccination rates are too low.) The FDA has been evaluating incoming data from studies on immunocompromised individuals who receive booster shots, and is expected to make its determination soon, CNN reports.
For everyone else, it’s not clear yet whether or not (or when) an additional COVID-19 vaccine dose may be helpful. People without compromised immune systems may eventually need booster shots if protection from the initial vaccine wears off over time, or the virus mutates in ways that make the original vaccine significantly less effective. The data to answer those questions are still coming in. (Some studies do indicate the mRNA vaccines are still pretty effective against the delta variant, but the dataset is evolving, and other variants are on the horizon.)
The CDC is currently examining the evidence on various groups of people (including the elderly and the young and healthy) to track how well immunity holds up over time. “What we’re doing, literally, on a weekly and monthly basis is following cohorts of patients to determine if, when, and whom should get [a booster shot],” Dr. Fauci said. “If the data shows, in fact, that the degree of protection has gone down below a critical level, that’s when you’re going to be hearing about the implementation of boosters.”
So as of now, boosters aren’t recommended for people who are not immunocompromised. “But we will be following [those groups of other people] very carefully,” Dr. Fauci said. “And if they do need it, we’ll be ready to give it to them.”