The claim: Immunity from infection is always stronger than immunity from vaccines
Millions of Americans are fully vaccinated against the coronavirus, but some anti-vaccine advocates online say they may have been better off getting sick.
The three coronavirus vaccines approved for emergency use in the United States are safe and effective at preventing serious COVID-19 cases, according to public health officials and peer-reviewed studies. As more Americans have received the vaccines, new COVID-19 cases have declined.
But Melissa Floyd says that immunity may not last very long.
“Natural immunity ALWAYS lasts longer than vac-induced immunity,” she wrote in a June 8 tweet, which she also shared on Facebook and Instagram. “For the few vacs that last 10-15 years, natural antibodies would have lasted a lifetime (or close to it). There has never been a pathogen where artificial immunity outperformed natural immunity.”
Floyd is a self-described “informed consent advocate” and co-host of “The Vaccine Conversation” podcast. With episode titles like “Does Vitamin D Work Better than the Flu Shot?” and “The REAL Reason We Are Seeing More Measles,” the podcast has been a source of vaccine skepticism and misinformation about coronavirus treatments in the past.
Disinformation aimed at undermining the public’s confidence in the coronavirus vaccines has surged online over the past several months. Floyd’s claim adds to it by misconstruing what’s known about coronavirus immunity.
Experts told USA TODAY both infection and vaccination are protective against the coronavirus. Scientists don’t yet know whether natural immunity or vaccine immunity lasts longer, given the limited time COVID-19 has existed. But research suggests vaccination provides more consistent protection against the virus.
While natural immunity tends to provide stronger protection against pathogens than vaccination, Floyd is wrong to say it always does — and getting vaccinated is far safer than getting sick.
“I am spending too much time debunking COVID falsehoods from the internet, and this is another one,” Grant McFadden, director of the Biodesign Center for Immunotherapy, Vaccines and Virotherapy at Arizona State University, said in an email.
Floyd did not respond to USA TODAY’s requests for comment.
How immunity works
People acquire disease immunity in two primary ways: infection and vaccination.
When humans are exposed to toxins or disease-carrying pathogens, the body creates antibodies to try to neutralize them. After infection, the body remembers how to create those pathogen-specific antibodies, decreasing the likelihood of future infections.
Vaccines help the body produce antibodies for specific pathogens without infection.
Most vaccines create what public health officials call an “imitation infection.” By introducing to the body inactivated or weakened viruses, or even pieces of viruses, vaccines trigger an immune response.
The COVID-19 vaccines, for example, teach cells how to make spike proteins lik
e those on the surface of the coronavirus. The body then produces antibodies against those proteins, building up immunity for future coronavirus infections.
Natural immunity tends to be stronger
Experts say that, in general, natural immunity does tend to provide stronger protection than vaccines.
“It is true that natural infection almost always causes better immunity than vaccines,” Children’s Hospital of Philadelphia says on its website. “Whereas immunity from disease often follows a single natural infection, immunity from vaccines usually occurs only after several doses.”
The reason why has to do with exposure.
When someone is vaccinated against a virus, they are only exposed to a portion of that virus or a weakened version of it. When someone gets sick, they’re exposed to the entire thing, meaning the immune response — and the symptoms that come with it — tends to be greater. In former COVID-19 patients, for example, “natural immunity is to the entire virus surface and not just the spike protein,” Dr. Marty Makary, chief of the Johns Hopkins Islet Transplant Center, told USA TODAY in an email.
But natural immunity isn’t a silver bullet.
“There are certainly scenarios where natural immunity is more robust than vaccine-elicited immunity, but no, it’s not always the case,” Shane Crotty, a professor and vaccine researcher at La Jolla Institute for Immunology, told USA TODAY. “Immunology’s complicated.”
Immunity depends on virus
In some cases, vaccination works better than natural immunity.
“It depends on the virus,” Vincent Racaniello, a microbiology and immunology professor at Columbia University, said in an email. “Many viruses encode proteins that antagonize immune defenses, hence immunity after infection may be suboptimal. Many vaccines eliminate these antagonists, so the immune response may be more durable.”
One example is human papillomavirus (HPV), for which vaccination provides more durable immunity than infection. The vaccine contains a higher concentration of proteins than the actual infection — which evades the body’s defenses — eliciting a stronger immune response. Research has indicated that the HPV vaccine lasts at least 10 years.
Vaccines for tetanus and pneumococcal also provide stronger immunity than the infection itself. Those are exceptions, experts say, but the coronavirus is an exceptional pathogen.
“Natural immunity tends to be stronger, yes,” Crotty said. “The reasons scientists and public health officials have been more cautious about COVID-19 is because of this big range that we’ve seen for COVID-19 in people, which seems different than some other infections.”
Scientists still studying coronavirus immunity
Eight experts told USA TODAY that while evidence suggests both natural and vaccine immunity to the coronavirus are strong, it’s too soon to say which one lasts longer.
First things first: Public health agencies say the coronavirus vaccines are highly effective at preventing serious COVID-19 cases.
Last year, more than 100,000 people participated in clinical trials for vaccines from Pfizer-BioNTech, Moderna and Johnson & Johnson. The first two vaccines were found to be about 95% effective at preventing COVID-19, while Johnson & Johnson’s shot was found to be about 72% effective (a number that was lower in part due to the higher volume of COVID-19 cases in the general population during the trial period). Subsequent studies of the vaccines outside of clinical trials support those numbers.
“So far, studies of lasting immunity to COVID-19 have been encouraging for both the vaccines and natural infections,” Dr. Ellen Foxman, an assistant professor of laboratory medicine and immunobiology at the Yale School of Medicine, said in an email. “However, keep in mind that this virus has only been around since late 2019/early 2020, and vaccines since later in 2020 — so no one can claim to know if immunity lasts for longer than that.”
Pfizer-BioNTech said in April that, according to data from its ongoing clinical trial, its vaccine is about 90% effective against COVID-19 for at least six months. Public health experts have said the protection likely lasts longer, partially because Pfizer reported its vaccine — which uses the same technology as Moderna’s shot — didn’t lose much of its efficacy after six months.
Early research is promising on the durability of natural immunity, too.
A research article published Feb. 5 in Science magazine found natural immunity can last at least eight months. More recent research, published May 24 in Nature, detected cells producing coronavirus antibodies in patients at least 11 months after they had mild COVID-19 cases.
Makary wrote in a recent Wall Street Journal column that there’s “ample scientific evidence that natural immunity is effective and durable.” Makary told USA TODAY that, for severe COVID-19 cases, antibody levels are “as high or even higher in some instances than what is seen after vaccinated immunity.”
However, the bottom line is that it’s too early to say whether immunity from infection is stronger than immunity from vaccination.
“We need robust clinical trials measuring reinfection rates in people who received the vaccine compared to those who got COVID-19 and recovered to really conclude whether or not there is a relevant difference,” Cynthia Anne Leifer, an immunology and microbiology professor at Cornell University’s College of Veterinary Medicine, said in an email. “Those trials are ongoing, so time will tell.”
COVID-19vaccines offer more consistent protection than infection
While the jury’s still out on whether natural immunity or vaccine immunity provides longer-lasting protection against COVID-19, research suggests that, overall, vaccination is the better bet.
Why? Vaccines provide more consistent protection, for starters.
“Recovery from COVID results in very variable immunity to a second infection, and this is reflected in the wide range of anti-spike antibodies in recovered patients,” McFadden said. “On the other hand, the immunity from the vaccines (especially the messenger RNA versions) is much more uniform, both in terms of protection from COVID and in anti-spike antibody levels.”
Preliminary research backs that up.
An April 20 paper awaiting peer review — and cited by Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases — found that people who had received two doses of shots from Pfizer or Moderna had antibody levels “up to 10 times” higher than those of a natural infection.
But those natural infection levels vary widely. The same Science magazine paper that found natural immunity lasts at least eight months also found some COVID-19 survivors had immunity levels 100 times higher than other survivors.
“So if you were playing a basketball game and one person scored one point and the other person scored 100 points, you would not consider those equivalent performances,” Crotty, one of the paper’s co-authors, told USA TODAY. “And so that’s the way we think about the immune responses as well. They’re there, but not everybody’s equal.”
Documenting whether people actually had COVID-19 instead of another illness is also a challenge. If you had COVID-19, took an antibody test, and found a “measurable, substantial antibody response, then you’re probably fine,” Crotty said. But even that’s not 100%.
Then there are the coronavirus variants.
“Antibodies elicited by infection do not neutralize the currently circulating coronavirus variants as efficiently as antibodies elicited by mRNA vaccination,” Scott Hensley, an associate professor of microbiology at the University of Pennsylvania, said in an email.
Public health officials are monitoring six notable variants circulating in the U.S., all of which appear to spread more easily than other coronavirus strains. It depends on the variant and vaccine, but research indicates the three coronavirus vaccines authorized for emergency use in the U.S. work at least to some degree against the variants.
“The higher your degree of immune response against the wild-type (coronavirus), the greater the secondary coverage you have against a wide array of variants,” Fauci said during a June 8 White House press briefing.
Vaccines are the safer option
Experts and public health officials say vaccination is also a better option than natural infection for the simple reason that someone doesn’t have to get sick to reap the benefits.
“To get immunity from a natural infection, you first have to get the infection — and risk a serious illness or having long-term health consequences,” Foxman said. “You also risk spreading the virus to friends and loved ones who might get a serious illness, even if you don’t. The main reason to get a vaccine is to get immunity without taking these health risks.”
If you’ve already had COVID-19 — and you can prove your body produced a measurable antibody response — experts still recommend getting at least one vaccine dose.
“My clinical advice to healthy patients with natural immunity is that one shot is sufficient, and maybe not even necessary, although it could increase the long-term durability of immunity,” Makary wrote for the Wall Street Journal.
Our rating: Partly false
The claim that immunity from infection is always stronger than immunity from vaccines is PARTLY FALSE, based on our research. While natural immunity tends to last longer than vaccine immunity, experts say it depends on the pathogen. Vaccines for HPV, tetanus and pneumococcal provide stronger immunity than the disease itself. Scientists are still studying the coronavirus, but evidence from experts, public health officials and research suggests COVID-19 vaccines provide more consistent and safer protection than infection.
Our fact-check sources:
- Melissa Floyd, June 8, Facebook
- Melissa Floyd, June 8, Twitter
- Melissa Floyd, June 8, Instagram
- Centers for Disease Control and Prevention, accessed June 8, COVID Data Tracker
- Food and Drug Administration, accessed June 8, COVID-19 Vaccines
- USA TODAY, May 28, Fact check: Peer-reviewed studies have shown safety, efficacy of COVID-19 vaccines
- USA TODAY, June 8, New infections drop below 15,000 for first time since March 2020, but summer surge is possible: Latest COVID-19 updates
- Johns Hopkins University Bloomberg School of Public Health, May 28, Why COVID-19 Vaccines Offer Better Protection Than Infection
- Apple Podcasts, accessed June 8, “The Vaccine Conversation with Melissa and Dr. Bob”
- Mother Jones, Sept. 23, 2020, The Terrifying Story of How QAnon Infiltrated Moms’ Groups
- Undark, April 16, 2020, How the Anti-Vaccine Community Is Responding to Covid-19
- Los Angeles Times, Sept. 3, 2019, Dr. Bob Sears’ views on vaccines have inspired loyal followers — and a crush of criticism
- The New York Times, Dec. 5, 2020, ‘Natural Immunity’ From Covid Is Not Safer Than a Vaccine
- Cynthia Anne Leifer, June 9, Email exchange with USA TODAY
- Dr. Marty Makary, June 9, Email exchange with USA TODAY
- Grant McFadden, June 9, Email exchange with USA TODAY
- Food and Drug Administration, accessed June 9, COVID-19 Vaccines
- Dr. Ellen Foxman, June 9, Email exchange with USA TODAY
- Yale Medicine, June 2, Comparing the COVID-19 Vaccines: How Are They Different?
- Centers for Disease Control and Prevention, accessed June 9, Key Things to Know about COVID-19 Vaccines
- Vincent Racaniello, June 9, Email exchange with USA TODAY
- USA TODAY, April 1, Pfizer COVID-19 vaccine is 90% effective for at least 6 months and protects against South Africa variant, study shows
- Pfizer, April 1, PFIZER AND BIONTECH CONFIRM HIGH EFFICACY AND NO SERIOUS SAFETY CONCERNS THROUGH UP TO SIX MONTHS FOLLOWING SECOND DOSE IN UPDATED TOPLINE ANALYSIS OF LANDMARK COVID-19 VACCINE STUDY
- Centers for Disease Control and Prevention, June 8, Frequently Asked Questions about COVID-19 Vaccination
- Detroit Free Press, Feb. 16. Misinformation about COVID-19 vaccines is everywhere. Here are the facts.
- Associated Press, April 22, How long does protection from COVID-19 vaccines last?
- USA TODAY, June 8, Fact check: COVID-19 vaccines don’t produce dangerous toxins
- Healthline, April 4, How Long Does Immunity from COVID-19 Vaccination Last?
- Science, Jan. 6, Immunological memory to SARS-CoV-2 assessed for up to 8 months after infection
- The Wall Street Journal, June 8, The Power of Natural Immunity
- Centers for Disease Control and Prevention, May 14, Largest CDC COVID-19 Vaccine Effectiveness Study in Health Workers Shows mRNA Vaccines 94% Effective
- Johns Hopkins Medicine, accessed June 10, The Immune System
- Centers for Disease Control and Prevention, accessed June 10, Immunity Types
- Children’s Hospital of Philadelphia, accessed June 10, Vaccine Safety: Immune System and Health
- Nature, May 24, SARS-CoV-2 infection induces long-lived bone marrow plasma cells in humans
- Scott Hensley, June 9, Email exchange with USA TODAY
- Insider, May 5, Dr. Fauci explains why COVID-19 vaccines work much better than natural immunity to protect you from the coronavirus
- Shane Crotty, June 10, Phone interview with USA TODAY
- bioRxiv, April 20, Distinct SARS-CoV-2 Antibody Responses Elicited by Natural Infection and mRNA Vaccination
- The Conversation, Sept. 14, 2020, Why a vaccine can provide better immunity than an actual infection
- La Jolla Institute for Immunology, Jan. 6, Protective immunity against SARS-CoV-2 could last eight months or more
- Centers for Disease Control and Prevention, accessed June 10, About Variants of the Virus that Causes COVID-19
- Medpage Today, May 5, Natural vs Vaccine Immunity for COVID: Is One More Effective?
- USA TODAY, June 9, Johnson & Johnson COVID-19 vaccine protects against virus variants, study shows
- USA TODAY, Jan. 25, Moderna says its COVID-19 vaccine protects against new UK and South African variants but plans to test new booster shot
- medRxiv, April 29, Previously infected vaccinees broadly neutralize SARS-CoV-2 variants
- Science, April 30, Prior SARS-CoV-2 infection rescues B and T cell responses to variants after first vaccine dose
- Science, March 25, mRNA vaccination boosts cross-variant neutralizing antibodies elicited by SARS-CoV-2 infection
- The White House, June 8, Press Briefing by White House COVID-19 Response Team and Public Health Official
- Virus Research, March 2, 2017, Evasion of host immune defenses by human papillomavirus
- Centers for Disease Control and Prevention, accessed June 10, HPV Vaccine Information For Young Women
- Mayo Clinic, accessed June 10, How do COVID-19 antibody tests differ from diagnostic tests?
- Centers for Disease Control and Prevention, July 2018, Understanding
How Vaccines Work
- Akiko Iwasaki, June 8, Email exchange with USA TODAY
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