(NEXSTAR) — People will likely need an annual COVID-19 vaccination over the next several years, Johnson & Johnson CEO Alex Gorsky told CNBC during an interview on Tuesday.

“I think most people feel that… likely, yes… for the next several years, we’ll be getting a COVID-19 shot just like we would a flu shot,” Gorsky told CNBC on Tuesday. “I think we could all imagine a future where we’re living with this… but where we can keep the science at pace with the virus… so we can keep on living our lives.”

As the virus mutates, additional variants will be discovered and will impact the treatment, according to Gorsky.

“Every time it mutates, it’s almost like another click of the dial so to speak where we can see another variant, another mutation that can have an impact on its ability to fend of antibodies or to have a different kind of response not only to a therapeutic but also to a vaccine,” Gorsky said.

The proactive efficacy of the vaccine may only last for one year before a “booster” or secondary vaccine will be needed. Pfizer and Moderna have both indicated they are preparing for that possibility.

Last week, Johnson & Johnson filed for emergency use authorization for its coronavirus vaccine. The vaccine was safe and offered strong protection against moderate to severe COVID-19, according to preliminary results from a massive international study.

It didn’t appear quite as strong as two-dose competitors made by Pfizer and Moderna — a finding that may be more perception than reality, given differences in how each was tested.

But the Food and Drug Administration is asking its independent advisers to publicly debate all the data behind the single-dose shot — just like its competitors were put under the microscope — before it decides whether to green light a third vaccine option in the U.S. The panel will meet Feb. 26.

Dr. Peter Marks, FDA’s vaccine chief, has cautioned against making comparisons before the evidence is all in.

“With so much need to get this pandemic under control, I think we can’t ignore any tool in the tool chest,” he told the American Medical Association last week. “We will have to do our best to try to make sure that we find the populations that benefit the most from each of these vaccines and deploy them in a very thoughtful manner.”

WHAT THE NUMBERS SHOW

Overall, the single-dose vaccine was 66% effective at preventing moderate to severe COVID-19, according to early findings from a study of 44,000 people in the U.S., Latin America and South Africa.

But it was 85% protective against the most serious symptoms — and starting 28 days after their shot, researchers found no one who got the vaccine needed hospitalization or died.

WEAKER BUT STILL FIGHTS MUTATING VIRUS

The one-dose option worked better in the U.S. — 72% effective against moderate to severe COVID-19 — compared with 66% in Latin America and 57% in South Africa, where a more contagious mutant virus is spreading.

Scientists have been looking for real-world evidence about how vaccines work as the world races to stay ahead of the rapidly mutating virus, and welcomed the news that the J&J option — while weaker — did still offer protection.

OTHER OPTIONS

In large U.S. studies, two doses of the Pfizer and Moderna vaccines proved 95% protective against any symptomatic COVID-19.

But those studies were finished before the record virus surges of recent months and the appearance of the worrisome mutants, meaning such testing might not turn out the same if repeated today.

J&J also is studying a two-dose version of its vaccine, but results won’t be available for several more months.

THE SOUTH AFRICA VARIANT

On Monday, the head of the World Health Organization said the emergence of new COVID-19 variants has raised questions about whether or not existing vaccines will work, calling it “concerning news” that the vaccines developed so far may be less effective against the variant first detected in South Africa.

Tedros Adhanom Ghebreyesus said at a media briefing that South Africa’s decision on Sunday to suspend its vaccination campaign using the AstraZeneca vaccine is “a reminder that we need to do everything we can to reduce circulation of the virus with proven public health measures.”

He said it was increasingly clear that vaccine manufacturers would need to tweak their existing shots to address the ongoing genetic evolution of the coronavirus, saying booster shots would most likely be necessary, especially since new variants of the virus are now spreading globally and appear likely to become the predominant strains.

Tedros added that WHO expected to make a decision “in the next few days” on whether it would recommend an emergency use listing for the AstraZeneca vaccine. That designation would allow millions of doses to be shipped to poor countries as part of a U.N.-backed effort to distribute COVID-19 vaccines worldwide known as COVAX.

Last week, Tedros said that more than three quarters of COVID-19 vaccines had been administered in just 10 countries and that immunization in nearly 130 countries had yet to start. Despite WHO’s aim of starting COVID-19 vaccination in poor countries at the same time as wealthy countries, COVAX hasn’t delivered any vaccine doses anywhere.

Dr. Soumya Swaminathan, WHO’s chief scientist, said people shouldn’t conclude from South Africa’s decision that the AstraZeneca vaccine doesn’t work. She said all of the available evidence to date shows the vaccines developed so far reduce deaths, hospitalizations and severe disease.

Other COVID-19 vaccines developed by Novavax, Pfizer and BioNTech and Johnson & Johnson also appear to be less effective against the strain first identified in South Africa, although they may prevent severe disease.

The Associated Press contributed to this report.