The Food and Drug Administration on Tuesday cleared the way for people who are at least 65 years old or immune-compromised to receive a second updated booster shot against the coronavirus, an option designed to bolster protection for the most vulnerable Americans even as the pandemic recedes.

The action appears likely to provide a measure of reassurance to people whose age or medical issues put them at risk of serious illness if they are infected by the coronavirus. Some got updated boosters last fall, soon after the omicron-targeting shots were authorized, but patients and physicians recognize the mRNA vaccines have a history of waning protection within months of administration.

Virus Outbreak Vaccine

Vials of the company’s updated COVID-19 vaccine during production in Kalamazoo, Mich. Pfizer via AP

People who are eligible for the extra boosters might be able to get them as soon as this week. Vaccine advisers to the Centers for Disease Control and Prevention are scheduled to meet Wednesday to discuss the second booster, and CDC Director Rochelle Walensky is expected to sign off quickly.

The bivalent booster, as it is known, targets omicron subvariants BA.4 and BA.5, as well as the original coronavirus. Older people will be able to get the booster once four months have passed since they received their first omicron-specific booster; for the immunocompromised, the minimum spacing is two months, assuming their doctors agree. The shots are made by Moderna and by Pfizer and its German partner, BioNTech.

Federal health officials will not formally urge that people get a second booster. Instead, the “permissive” policy says they may get a second dose if they want.

Even as some people have been clamoring for a second booster, others appear unconcerned. Only about 42 percent of people 65 and older have received the first bivalent booster, according to the CDC.


Experts have expressed differing views on the necessity of a second bivalent dose. While some say little data exists to justify it, others believe the extra shot is a good option for high-risk individuals. The United Kingdom and Canada already are offering spring booster shots for vulnerable individuals.

“It seems like a pretty easy call – given the risks of COVID in the immunocompromised population and the good safety record of the vaccine,” said Eric J. Rubin, a member of the FDA’s advisory committee on vaccines and editor in chief of the New England Journal of Medicine. “It seems like a reasonable strategy.”

Jesse L. Goodman, professor of medicine and infectious diseases at Georgetown University Medical Center and former chief scientist at the FDA, agreed, saying that a second booster targeted to those at high risk “makes good sense.” But he added that more studies are needed not only to improve vaccines but also to determine how best to use them.

Federal officials concede extensive information about the booster is lacking. But they say data indicates that the booster is beneficial against serious illness, although its durability fades some months after it is given, just as with the original vaccine.

A recently published Israeli study of the bivalent booster made by Pfizer and BioNTech compared people 65 and older who got the shot with those who did not. Those who received the booster had a 72 percent lower risk of covid-related hospitalization and a 68 percent lower risk of covid-related death, according to the study published in the journal Lancet Infectious Diseases.

“Bivalent mRNA booster vaccination in adults aged 65 years or older is an effective and essential tool to reduce their risk of hospitalisation and death due to COVID-19,” wrote study co-author Ronen Arbel of Clalit Health Services, a health-care organization in Israel.


A recent Finnish analysis that has not been peer reviewed also found that the updated booster reduced risk of hospitalization and death from COVID-19 for people 65 and older.

In addition, unpublished data presented at the CDC’s vaccine advisory panel meeting in February confirmed earlier real-world reports that bivalent vaccines are providing protection against serious illness in adults, compared with people who received previous doses of the original vaccine and no omicron-targeting dose.

Federal officials have noted they are not advocating a second omicron booster for young people, who in rare cases can experience heart-related side effects after getting the vaccine.

The FDA on Tuesday also retired the original mRNA vaccines by Moderna and Pfizer-BioNTech in favor of the updated shots.

The FDA still plans to move to a once-a-year coronavirus vaccine shot for most Americans – a timetable announced in January that is intended to coincide with annual flu inoculations in the fall. The FDA and its advisers hope the simplified schedule will encourage more people to get coronavirus vaccine doses. Officials will select a reformulated dose in coming months based on which coronavirus strain scientists think is most likely to be circulating in fall and winter.

Under that blueprint, most people, whether vaccinated or not, would be urged to receive a single annual dose of a coronavirus shot.


For now, older adults or those with weak immune systems will be eligible for two or more bivalent doses, the FDA said. And, at this time, families with young children who have not completed their initial vaccine series should consult with their pediatricians on how many shots they should get.

The updated shot will be free of charge, regardless of insurance coverage, because the government has an ample supply.

Even after the federal supply is gone, shots will continue to be free of charge to most people with private and public health insurance. But once federally purchased doses are depleted, uninsured and underinsured adults may have to pay, and privately insured people may need to confirm that their provider is in-network, according to an analysis by the Kaiser Family Foundation, a health-policy organization.

An omicron subvariant, XBB.1.5, accounts for almost 80 percent of cases now being diagnosed in the United States, according to the CDC. Another omicron descendant, XBB.1.6, which is called Arcturus and is spreading rapidly in India, is responsible for about 7 percent of U.S. cases.

Comments are no longer available on this story