Do you need a COVID booster shot every year?

San Diego (KGTV)-As millions of people get COVID-19 vaccine booster shots, many are wondering if this will be needed each year. But experts agree that the question does not have an easy answer.

“We know that COVID-19 will stay for some time,” says Suzanne Shea, VP of Systems Pharmacy at Sharp Healthcare. “And, based on the research we’re looking at, it has certain implications that it will be routine. We just don’t know what it is yet.”

Some experts tried to answer, but few found a consensus.

In August, CDC director Dr. Rochelle Walensky told CBS News that he didn’t think he needed an annual COVID booster.

“After this third dose, you seem to get a really strong response,” she said in an interview. “I definitely don’t want to say this virus because it’s humble, but I don’t necessarily expect it to be needed every year.”

However, Pfizer’s CEO disagrees. That same month, CEO Albert Bourla told Business Insider, “This is the scenario that is most likely to require annual re-vaccination, as is the case with the flu vaccine.”

Shea states that these discrepancies are expected because doctors can only take what she calls “knowledge-based guesses,” based on the limited data we have seen so far.

But she reminds everyone who asks that we still have a lot to learn.

“In very healthy people, immunity can last much longer than in poor health,” Shea says. “It hasn’t been decided yet.”

Meanwhile, researchers at the Lahora Institute of Immunology are trying to find a concrete answer to boosters and protection against COVID.

In addition to ongoing research on COVID-19 immunity, they have launched two new studies. Find out how booster shots increase the immune response in both antibodies and T cells. Other studies will investigate whether the breakthrough COVID-19 infection boosts immunity and replaces booster shots.

Related: La Jolla Institute is comprehensively investigating COVID-19 vaccine immunity

Dr. Alessandro Sette is leading some research. He told ABC10 News that the answer is complicated because no one has identified an antibody or cell-level threshold that corresponds to defense.

Dr. Sette also says that the level depends on whether the vaccine provides immunity from infection or protection against severe illness.

“You may have a level of immunity that is completely sufficient to prevent severe illness, but not enough to prevent infection,” says Dr. Sette.

Booster shots have been part of medicine for decades. Some people are vaccinated against the flu every year. The tetanus vaccine requires a booster every 10 years. For other illnesses such as hepatitis, a three-dose regimen is sufficient to provide lifelong protection.

However, those vaccines have been studied for many years. The COVID-19 shots are only a few years old, but the booster shots have started within the last two months.

Dr. Sette believes that an additional 6-8 months of data is needed to get a real answer on the duration of protection after a booster shot.

Nevertheless, he believes that ongoing research on the initial dose of the vaccine may provide hope that continuous booster immunization may not be needed.

“From what we’ve seen, vaccination provokes a memory response,” says Dr. Sette. “The memory response can last for years, so I think there’s a reason to be reasonably optimistic here.”

Age is another factor in booster durability. Some doctors believe that people in these categories may require additional booster immunity, as COVID has a more serious impact on the elderly and immunodeficiency. Conversely, they say people who do not belong to high-risk groups may not.

For kids just starting to get their first shot, it can take a year or more to figure out if they need a booster.

“When you enter adulthood, how long does their immunity last compared to someone who is an adult today?” Shea asks. “There is more research to be done and done.”

The length of the pandemic also affects this. The longer it lasts, the more likely you are to see another variant that may require additional shots. And more cases mean that there is a high probability of infection.

Doctors say that if so, higher levels of immune protection may be needed.

That’s why many say it’s more important to make sure that everyone who needs to get a shoot or booster now gets it in order to control the pandemic. That way, you can worry about future additional doses.