Dr. Anthony Fauci said Sunday that some Americans with weakened immune systems may be among the first to need a COVID-19 vaccine booster shot. But at this point, he said the matter is still a “dynamic situation.”
“Those who are transplant patients, cancer chemotherapy, auto-immune diseases, that are on immunosuppressant regimens, those are the kind of individuals that if there’s going to be a third booster, which might likely happen, would be among first the vulnerable,” Fauci said during a CNN interview.
With the highly contagious Delta variant spreading rapidly, health officials are scrutinizing the latest scientific data in order to determine when to recommend booster doses.
Israel, which started vaccinating its population before many other countries, has already begun administering a third dose of Pfizer’s vaccine to adults with compromised immune systems. U.S. officials said previously that they don’t think booster doses are necessary for the general public yet.
Officials examining the data
Fauci, who is the director of the National Institute of Allergy and Infectious Diseases, said the issue of booster doses is being regularly assessed with the aim of ensuring that vulnerable people don’t experience an increase in their risk of contracting the virus over the coming months.
“It’s a dynamic situation. It’s a work in progress, it evolves like in so many other areas of the pandemic,” said Fauci. “You’ve got to look at the data.”
He cited studies, such as a small study out of Israel, suggesting that vaccinated people could experience a decline in immunity over time. A potential drop in efficacy is particularly concerning because of the aggressive nature of the Delta variant.
Earlier this month, Pfizer said it intends to seek booster dose authorization from the FDA in light of the data coming out of Israel.
"It's a small data set, but I think the trend is accurate: Six months out, given that Delta is the most contagious variant we have seen, it can cause infections and mild disease," said Mikael Dolsten, Pfizer's chief scientific officer.
On Friday, Pfizer and its partner BioNTech said the U.S. had purchased 200 million additional doses of their vaccine to support the pediatric vaccination effort as well as possible booster shots.