The US Food and Drug Administrationindependent panel of advisors raised doubts about the need update “regularly”. Covid vaccines, noting that it is not clear whether the virus is seasonal like the flu.

Counselors on Thursday voted unanimously that the new shots in the autumn should be monovalent – ​​meaning they are designed against one variant of Covid – and target one of omicron XBB strains. They are now dominant variants national.

But the original ballot question included a statement on whether the panel recommends “regular updating” of Covid images.

Dr. Peter Marks, head of the FDA’s vaccine division, asked the panel chairman to strike the wording from the question after several advisers raised concerns.

“The way it was worded, it seems to be saying, do we agree that it will need to be updated periodically? And I don’t think that’s clear,” said Dr. Arthur Reingold, professor of epidemiology at the University of California, Berkeley.

The panel’s concerns suggest there is still uncertainty about what the Covid pandemic will look like in the coming years, even as the number of cases and deaths declines nationally.

The concerns are also the latest backlash against the FDA proposed shift for the annual Covid vaccination earlier this year – a simplified approach to vaccination which would include annual vaccination updates. It’s similar to how the US rolls out new flu vaccines every fall and winter, which is when cases boom.

However, several advisers warned against labeling Covid as seasonal, like the flu.

“It’s not clear to me yet that this is a seasonal virus,” said Henry Bernstein, a pediatrician at Cohen Children’s Medical Center.

Dr. Mark Sawyer, a professor of clinical pediatrics at the University of California, San Diego, added that describing Covid as “seasonal” could end up confusing the public about “when and where they should get vaccinated and how often”.

“I’m going to join the chorus here. I think the use of the word season is just as problematic,” he said. Dr. Sawyer. “It’s linking the campaign to the flu vaccine. I understand that it may be convenient and most effective to give the vaccines together, but it’s only been a few years and we really don’t know what the Covid season is.”

Unlike the flu, the spread of Covid has often been erratic. The virus is constantly mutating into new variants and has yet to settle into a predictable seasonal pattern.

In response to the advisor, the FDA’s Marks emphasized that the Covid shots will likely require another update “at some point.”

“This is not going to be the final formulation for this vaccine forever,” he said.

The move to an annually updated Covid vaccine is supported by former White House health officials Dr. Ashish Jha and Dr. Anthony Fauci, who believe the country could benefit from adopting a similar approach to flu shots.

Each year, researchers evaluate the flu strains in circulation and estimate which will be most common during the fall and winter before updating the shots.

“People go and get their annual flu shot if they think it’s a routine part of care. I don’t — every time I get a flu shot, I don’t think it’s my 28th flu shot or my 29th flu — I just think , that it’s my annual flu shot,” Jha said on Wednesday Conversation on the PBS News Hour.

“For most people, if they think of it as their annual COVID vaccine, they get it when they get their flu shot, I think that’s going to be an important difference,” he continued.

Recent polls suggest the public is open to the idea.

More than half of about 1,200 U.S. adult respondents said they would be likely to get an annual Covid vaccine if it were offered similar to the annual flu shot, according to an April survey organization for health policy KFF. This includes 32% who would be “very likely” to do so.

It’s unclear how many Americans will roll up their sleeves this fall and winter to get the updated shots.

The uptake of the latest bivalent boosters – which target the original strain of Covid and omikron BA.4 and BA.5 – has been slow.

Just about 17% of the US population — received by roughly 56 million people Pfizer and Modern boosters since their approval in September, according to the Centers for Disease Control and Prevention.

The leading manufacturer of the Covid shot Pfizer he told CNBC last month, the annual Covid plan could encourage more people to get vaccinated each year.

The shift could help people see Covid shots as just another “very natural part” of protecting their health, said Dr. Mikael Dolsten, Chief Scientist at Pfizer.

Pfizer is already preparing to switch to an annual plan by developing “next-generation” versions of its shots that aim to extend and prolong the protection people get from the virus for a full year.