An 18-year-old video of Dr. Anthony Fauci talking about the strength of natural immunity is making the rounds on social media, with some users alleging the director of the National Institute of Allergy and Infectious Diseases is ignoring the science now when it comes to COVID-19.

“Check out this clip of Dr. Fauci in 2004 talking about the STRENGTH of Natural Immunity,” reads an April 1 Facebook post. “Fast forward 18 years, what happened to this ‘science?!’ Why does Fauci continue to LIE to the American people?!”

The post was flagged as part of Facebook’s efforts to combat false news and misinformation on its News Feed. (Read more about our partnership with Facebook.)

Fauci’s statements were made in the context of an hour-long discussion about influenza, not COVID-19, the NIAID said in a statement to PolitiFact. Fauci supports the Centers for Disease Control and Prevention’s recommendation that people who have recovered from COVID-19 still get vaccinated, the agency said.

Fauci’s public statements since the pandemic began show that he has not completely discounted the amount of protection natural immunity provides from COVID-19, but he has expressed uncertainty about how long the protection lasts with regard to this particular virus.

What Fauci said in 2004

Fauci’s 2004 comments on immunity came on C-SPAN’s Washington Journal after a caller suffering from the flu talked about her bad experiences with the influenza vaccine. The relevant portion of the interview begins at the 28-minute mark.
Host Peter Slen asked Fauci: “She’s had the flu for 14 days. Should she get a flu shot?”

Fauci: “Well, no, if she got the flu for 14 days, she’s as protected as anybody can be, because the best vaccination is to get infected yourself.

“If she really has the flu, if she really has the flu, she definitely doesn’t need a flu vaccine. If she really has the flu.”

Slen: “She should not get it again this year?”

Fauci: “She doesn’t need it, because the most potent vaccination is getting infected yourself.”

Influenza and COVID-19 are both contagious respiratory viruses, but require different public health responses. While the flu can be caught year-round, generally it peaks between December and February. The CDC recommends people get flu vaccines once a year.

COVID-19 is not seasonal, spreads more easily and is far deadlier than the flu.

The CDC said there have been 3.5 million flu illnesses, 34,000 hospitalizations and 2,000 deaths in the U.S. from the flu so far in the 2021-22 season. There have been more than 982,000 deaths from COVID-19 in the U.S. since 2020 and nearly 600,000 of those came in 2021, according to Johns Hopkins University data.

Dr. Nicole Iovine, an epidemiologist at the University of Florida’s Division of Infectious Diseases and Global Medicine, said that in 2004 our knowledge about immunity against respiratory viruses was more limited than it is today, and there was a shortage of influenza vaccines due to manufacturing issues, so that may have factored into Fauci’s advice. The NIAID confirmed that shortage played a role in Fauci’s answer.

At that time, Iovine said, flu vaccines were trivalent, meaning they were designed to guard against three flu viruses. Today, they are designed to protect against four flu viruses.

So, when Fauci was speaking, Iovine said, “the benefit of flu vaccination after having the flu was somewhat diminished.”

Why should people who’ve had COVID-19 get vaccinated?

While Fauci told the viewer nearly two decades ago that she didn’t need the vaccine if she recently had the flu, he and the CDC recommend people get vaccinated against COVID-19 after they’ve recovered from the virus.

That’s for a couple of reasons. The CDC says on its website that studies show a reduced risk of reinfection in people who have had the virus and been vaccinated because the vaccine provides added protection to the immune system.

NIAID said there is no currently available reliable test to show if someone is protected against reinfection just from having the virus. Immunity from prior infection appears to have protective benefits, the agency said, but the level and durability of the protection is still unclear.

What Fauci has said about COVID-19 vaccines

Fauci also hasn’t discounted protection from natural immunity and has spoken encouragingly about it on several occasions.

In March 2020, early in the pandemic, Fauci expressed optimism — and uncertainty — about how effectively natural immunity from the virus could ward off reinfection in an interview with “The Daily Show” host Trevor Noah.

“We don’t know that for 100% certain, because we haven’t done the study to see rechallenges, whether they’ve been protected,” Fauci said. “But I feel really confident that if this virus acts like every other virus that we know, once you get infected, get better, clear the virus, then you’ll have immunity that will protect you against reinfection. So it’s never 100% but I’d be willing to bet anything that people who recover are really protected against reinfection.”

Fauci also spoke about natural immunity on Sept. 9, 2021, in an interview with CNN’s Anderson Cooper and Dr. Sanjay Gupta. Gupta raised a study out of Israel that showed a strong immune response in those who had the virus and asked Fauci why people should still get vaccinated.

Fauci said there could be a good argument for not getting the vaccine based on the study, but didn’t “have a firm answer” for Gupta. He also questioned the durability of the immune response, and said more discussion was needed.

“The one thing that paper from Israel didn’t tell you is whether or not as high as the protection is with natural infection, what’s the durability compared to the durability of a vaccine?” Fauci said. “So it is conceivable that you got infected, you’re protected, but you may not be protected for an indefinite period of time.”

He spoke on the issue again in an April 30, 2021, radio interview with Latino USA’s Maria Hinojosa. Fauci explained why Hinojosa should get vaccinated even though she had COVID-19 a year ago.

“It’s very likely that if you didn’t get the vaccine, your antibodies levels will start going down and down and down and down and then you might get vulnerable to reinfection, which we’ve seen in some people,” Fauci told her.

Iovine said that immunity to COVID-19 declines after both natural infection and vaccination and scientists don’t entirely know why immunity isn’t more durable compared to typical childhood vaccines.

“Since both flu and COVID cause significant mortality, the best personal and public health strategy is to get vaccinated, rather than take the chance that one will recover from natural infection,” said Iovine.

“The bottom line is that we should not be following 18-year-old medical advice when there is much more up-to-date, relevant and evidence-based information available to us,” Iovine said.

Our ruling

Social media users are using a 2004 video of Fauci praising the strength of natural immunity to influenza to suggest he’s ignoring that science when it comes to COVID-19.

Fauci’s comments in that video were specific to a question from a woman who was suffering from influenza. COVID-19 is a different and more deadly virus, and there’s no reliable test that shows the durability of immunity from an infection.

Regarding COVID-19, Fauci has also spoken positively about protection from natural immunity, but questioned its durability. He recommends, as does the CDC, that people also get vaccinated for added protection.

We rate this claim False.

This article was originally published by PolitiFact, which is part of the Poynter Institute. It is republished here with permission. See the sources for these fact checks here and more of their fact checks here.