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Is pivoting to an annual COVID-19 shot a smart move? The FDA, which proposed the change on Monday, says an annual shot vs. periodic boosters could simplify the process to ensure more people stay vaccinated and protected against severe COVID-19 infection. 

A national advisory committee plans to vote on the recommendation Thursday.

If accepted, the vaccine formula would be decided each June and Americans could start getting their annual COVID-19 shot in the fall, like your yearly flu shot.

Keep in mind: Older Americans and those who are immunocompromised may need more than one dose of the annual COVID-19 shot.

Most Americans are not up to date with their COVID-19 boosters. Only 15% of Americans have gotten the latest booster dose, while a whopping nine out of 10 Americans age 12 or older finished their primary vaccine series. The FDA, in briefing documents for Thursday’s meeting, retin a 0.1 crema precio says problems with getting vaccines into people’s arms makes this a change worth considering. 

“Given these complexities, and the available data, a move to a single vaccine composition for primary and booster vaccinations should be considered,” the agency says.

A yearly COVID-19 vaccine could be simpler, but would it be as effective? WebMD asks health experts your most pressing questions about the proposal.

Pros and Cons of an Annual Shot

Having an annual COVID-19 shot, alongside the flu shot, could make it simpler for doctors and health care providers to share vaccination recommendations and reminders, according to Leana Wen, MD, a public health professor at George Washington University and former Baltimore health commissioner.

“It would be easier [for primary care doctors and other health care providers] to encourage our patients to get one set of annual shots, rather than to count the number of boosters or have two separate shots that people have to obtain,” she says.

“Employers, nursing homes, and other facilities could offer the two shots together, and a combined shot may even be possible in the future.”

Despite the greater convenience, not everyone is enthusiastic about the idea of an annual COVID shot. COVID-19 does not behave the same as the flu, says Eric Topol, MD, editor-in-chief of Medscape, WebMD’s sister site for health care professionals.

Trying to mimic flu vaccination and have a year of protection from a single COVID-19 immunization “is not based on science,” he says. 

Carlos del Rio, MD, of Emory University in Atlanta and president of the Infectious Diseases Society of America, agrees. 

“We would like to see something simple and similar like the flu. But I also think we need to have the science to guide us, and I think the science right now is not necessarily there. I’m looking forward to seeing what the advisory committee, VRBAC, debates on Thursday. Based on the information I’ve seen and the data we have, I’m not convinced that this is a strategy that is going to make sense,” he says. 

“One thing we’ve learned from this virus is that it throws curveballs frequently, and when we make a decision, something changes. So, I think we continue doing research, we follow the science, and we make decisions based on science and not what is most convenient.”

COVID-19 Isn’t Seasonal Like the Flu

“Flu is very seasonal, and you can predict the months when it’s going to strike here,” Topol says. “And as everyone knows, COVID is a year-round problem.” He says it’s less about a particular season and more about times when people are more likely to gather indoors. 

So far, European officials are not considering an annual COVID-19 vaccination schedule, says Annelies Zinkernagel, MD, PhD, of the University of Zurich and president of the European Society of Clinical Microbiology and Infectious Diseases. 

Regarding seasonality, she says, “what we do know is that in closed rooms in the U.S. as well as in Europe, we can have more crowding. And if you’re more indoors or outdoors, that definitely makes a big difference.”

Which Variant(s) Would It Target?

To decide which variants an annual COVID-19 shot will attack, one possibility could be for the FDA to use the same process used for the flu vaccine, Wen says.

“At the beginning of flu season, it’s always an educated guess as to which influenza strains will be dominant,” she says.

“We cannot predict the future of which variants might develop for COVID, but the hope is that a booster would provide broad coverage against a wide array of possible variants.”

Topol agrees it’s difficult to predict. A future with “new viral variants, perhaps a whole new family beyond Omicron, is uncertain.”

Reading the FDA briefing document “to me was depressing, and it’s just basically a retread. There’s no aspiration for doing bold things,” Topol says. “I would much rather see an aggressive push for next-generation vaccines and nasal vaccines.”

To provide the longest protection, “the annual shot should target currently predominant circulating strains, without a long delay before booster administration,” says Jeffrey Townsend, PhD, a professor of biostatistics and ecology and evolutionary biology at Yale School of Public Health. 

“Just like the influenza vaccine, it may be that some years the shot is less useful, and some years the shot is more useful,” he says, depending on how the virus changes over time and which strain(s) the vaccine targets. “On average, yearly updated boosters should provide the protection predicted by our analysis.”

Townsend and colleagues published a prediction study on Jan. 5, in the Journal of Medical Virology. They look at both Moderna and Pfizer  vaccines and how much protection they would offer over 6 years based on people getting regular vaccinations every 6 months, every year, or for longer periods between shots. 

They report that annual boosting with the Moderna vaccine would provide 75% protection against infection and an annual Pfizer vaccine would provide 69% protection. These predictions take into account new variants emerging over time, Townsend says, based on behavior of other coronaviruses.

“These percentages of fending off infection may appear large in reference to the last 2 years of pandemic disease with the massive surges of infection that we experienced,” he says. “Keep in mind, we’re estimating the eventual, endemic risk going forward, not pandemic risk.”


Leana Wen, MD, public health professor, George Washington University; former Baltimore health commissioner. 

Eric Topol, MD, editor-in-chief, Medscape. 

Carlos del Rio, MD, professor of medicine, Emory University, Atlanta; president, Infectious Diseases Society of America.

Annelies Zinkernagel, MD, PhD, University of Zurich; president, European Society of Clinical Microbiology and Infectious Diseases.

Jeffrey Townsend, PhD, Elihu professor of biostatistics, professor of ecology & evolutionary biology, Yale School of Public Health. 

FDA, briefing document, Jan. 26, 2023. 

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