There’s growing consensus among scientists that people who received two shots of COVID-19 vaccine will eventually need a third, but the timing and urgency of those booster shots remains unclear, according to an infectious disease expert at Duke University.
Dr. Cameron Wolfe said Wednesday that more data is needed to determine when people who are not at high risk of getting sick or dying of COVID-19 should get a booster shot. So far, very few vaccinated people with healthy immune systems and no underlying health risks are getting sick enough from COVID-19 to end up in the hospital.
“So when we talk about boosting for individuals in the general community, I want to be very clear that that is far less important than still reaching those individuals who are not yet vaccinated at all,” Wolfe said. “We need to continue to talk to those individuals about safety data and how robust it is and about the profound difference in their risk of hospitalization and death by the single act of getting vaccinated.”
The White House announced two weeks ago that vaccine boosters would be available this fall, pending approval of the U.S. Food and Drug Administration and under guidelines to be set by the U.S. Centers for Disease Control and Prevention. So far, neither of those agencies have approved the White House plan.
The FDA has authorized use of a third dose of the Pfizer-BioNTech and Moderna vaccines by people with certain health conditions that compromise their immune systems. Studies had shown that two doses have not provided the desired protection for this group, who are more likely to get seriously ill with COVID-19.
Wolfe said this “small niche” of the population includes those who have had kidney, heart, lung or liver transplants; are undergoing chemotherapy; have HIV; or are taking drugs to suppress their immune systems to treat conditions such as lupus, rheumatoid arthritis or multiple sclerosis.
“We’re trying to carve out a group of individuals who we know to be at high risk of severe COVID,” he said. “We know that their on-average response is poorer to vaccines, so we’re trying to get them a little bit more.”
Wolfe said studies in Israel and the United Kingdom suggest that the protection provided by the Pfizer and Moderna vaccines begins to wane six to eight months after the second dose. But, he said, that has not yet resulted in a substantial increase in the number of vaccinated people who get sick enough from the coronavirus to end up in the hospital.
That raises questions about if and when healthy people who don’t face unusual risks of contracting the virus should get a third shot of vaccine, Wolfe said. He said if the FDA approves, he would support boosters for health care workers and nursing home residents, the first two groups that qualified for vaccination when it became available last December.
“If there’s going to be a larger load to bear for people getting infected and having breakthroughs, it’s going to be front and center with health care workers and older adults first,” he said.
But Wolfe said he’d like to see more data that would show whether providing booster shots to the wider population would provide any benefit. He gave an example of a 35-year-old healthy person who doesn’t work in health care or other risky situation.
“I think we need to still see a little more data to fully understand why that person would need to be boosted and if that’s absolutely crucial,” he said.