“The fact of the matter is it looks like natural immunity is as strong if not stronger than vaccinated immunity. ... There is a risk to the vaccine. Again, it’s very small, but there are some pretty serious side effects, including death. We are already over 5,200 deaths reported on the VAERS system. That’s a CDC, FDA’s early warning system.”

— Sen. Ron Johnson (R-Wis.), in an interview on “Hannity” on Fox News, July 14

Johnson has emerged as the leading vaccine skeptic in Congress this year.

For months, the senator has been peddling misinformation about coronavirus vaccines, undeterred by fact checkers, federal health agencies, medical experts and a growing body of scientific research.

We previously dug into two Johnson claims that resurfaced in this interview on Fox News, a network whose right-wing personalities consistently bash the Biden administration’s vaccination efforts.

More cases and research studies have accumulated since our fact checks were published, but Johnson’s statements remain unsupported by science.

The Facts

‘Natural immunity is as strong if not stronger’

Doctors, public health experts and the Centers for Disease Control and Prevention are clear: Get the coronavirus vaccine even if you had covid-19.

People who had the disease will naturally produce antibodies that build immunity against a repeat infection. But natural immunity can fade over time and its duration varies by person, several scientific studies have shown. Reinfections, both mild and severe, are rare but have been well-documented since the coronavirus emerged in late 2019. That’s because different people tend to have different responses to an infection.

A study from January in the New England Journal of Medicine found that the Moderna vaccine “has the potential to provide durable humoral immunity,” whereas “natural infection produces variable antibody longevity.” An NEJM study published in March compared two groups of people taking the Pfizer-BioNTech and Moderna vaccines: some who previously had covid-19 and some who did not. The recovered patients generally had higher antibody counts at the start of the vaccination period, but not in all cases, and by the end of the vaccination period both groups had similarly high antibody levels.

A study released in April by researchers at the University of California, Irvine, which has not been peer-reviewed, found that mRNA vaccines in a small number of subjects produced up to 10 times higher antibody titers "than convalescent plasmas from donors who recovered from natural infection.”

Recent studies also show that the mRNA vaccines could better protect against new coronavirus variants than natural immunity, according to a blog post June 22 by Francis Collins, the director of the National Institutes of Health.

“The new evidence shows that protective antibodies generated in response to an mRNA vaccine will target a broader range of SARS-CoV-2 variants carrying ‘single letter’ changes in a key portion of their spike protein compared to antibodies acquired from an infection,” Collins wrote about a study published in June by the journal Science Translational Medicine. “These results add to evidence that people with acquired immunity may have differing levels of protection to emerging SARS-CoV-2 variants. More importantly, the data provide further documentation that those who’ve had and recovered from a covid-19 infection still stand to benefit from getting vaccinated.”

A different study published in Science magazine June 25 showed that “after one dose of the Pfizer mRNA, people who had been previously infected actually showed enhanced both T-cell immunity as well as neutralizing antibodies not only against the wild type, but interesting, as I alluded to several sessions ago, you even get some spillover of infection against variants,” Anthony S. Fauci, the director of the National Institute of Allergy and Infectious Diseases and chief medical adviser on covid-19 to President Biden, said at a White House briefing May 5.

Another study from the same issue of Science found that a single shot of the Pfizer or Moderna vaccine “boosted neutralizing titers against all [covid-19] variants and [SARS] by up to 1000-fold” in subjects who previously had covid-19.

Jennifer Pisano, a professor of medicine and infectious-disease expert at the University of Chicago Pritzker School of Medicine, summed up the current body of knowledge in a blog post:

Is it better to gain immunity through exposure to covid-19 or through a vaccine?
With some viruses, such as chicken pox, being infected with the virus itself grants stronger immune protection than the chicken pox vaccine; however, in those cases, you then have to deal with all the complications of having the virus. When it comes to COVID-19, it’s really hard to know whether being exposed to the virus is more protective of future infection than the vaccine, simply because we don’t know the SARS-CoV-2 virus well enough yet.
With natural immunity, which is the protection we get after being infected with a virus, the immune response can be variable. For example: the number of antibodies your body produces may depend on how much of the virus you’re exposed to. And there is likely beneficial variation in the types of antibodies being produced. The vaccinations currently available in the U.S. have been shown to effectively stimulate antibodies against the virus’ spike protein. New vaccines are being created that make antibodies to other parts of the virus as well. Both immunity from natural infection and vaccination stimulate a T-cell response that will hopefully provide you with protection from the virus for a longer time.
While it’s possible some people may have a higher antibody response after a natural infection than they would after vaccination, we’re still learning about this new virus, and we don’t know how protective natural immunity really is, especially when there is such a continuum of different types of infections. We don’t have clear data on how antibody responses from a mild infection compare to a severe infection, or how protective those antibody responses are.
On the other hand, we do know that the vaccine is very protective. In most people, getting vaccinated generates a lot of antibodies. So far, the vaccines appear to be incredibly effective, especially when it comes to preventing severe infections, hospitalizations and death.

“Yes, you should be vaccinated regardless of whether you already had covid-19,” the CDC says. “That’s because experts do not yet know how long you are protected from getting sick again after recovering from covid-19. Even if you have already recovered from covid-19, it is possible — although rare — that you could be infected with the virus that causes covid-19 again. Studies have shown that vaccination provides a strong boost in protection in people who have recovered from covid-19.”

Johnson spokeswoman Alexa Henning referenced a study published in February by Science magazine that looked at not just antibody levels but all four main components of “immunological memory” — antibodies, B cells and two types of T cells. Each component grew or diminished at different rates, the study says.

The researchers analyzed “254 samples from 188 COVID-19 cases, including 43 samples at 6 to 8 months after infection” and said “our data show immune memory in at least three immunological compartments was measurable in ~95% of subjects 5 to 8 months PSO [post-symptom onset], indicating that durable immunity against secondary COVID-19 disease is a possibility in most individuals.”

This study also says that “it is well recognized that the magnitude of the antibody response against SARS-CoV-2 is highly heterogeneous between individuals” and that it’s “possible that a fraction of the SARS-CoV-2–infected population with low immune memory would become susceptible to reinfection relatively soon.”

Henning also pointed to an Israeli study that found both the Pfizer “vaccine and prior SARS-CoV-2 infection are effective against both subsequent SARS-CoV-2 infection and other COVID-19-related outcomes.” The same study noted “the remarkable curtailing of the outbreak in Israel which followed the high vaccine uptake by the Israeli population.”

Johnson’s interviewer, Sean Hannity of Fox News, also made a Pinocchio-worthy claim right before the senator.

“If you had covid, you had stated publicly you had it — well, the Cleveland Clinic is highly respected science research, right? They say that you wouldn’t need any vaccine,” Hannity said.

In fact, the Cleveland Clinic recommends that all eligible people get vaccinated.

“We recently shared research that provides insight into how the immune system protects the body after a confirmed covid-19 infection. The study followed Cleveland Clinic caregivers over five months as the vaccination process was beginning. The data showed that the vaccine was extremely effective in preventing covid-19 infection. In addition, we found that none of the previously infected employees who remained unvaccinated were reinfected over the duration of the study. This information could help guide vaccination efforts should there be a shortage of vaccine supply and in countries where vaccine supply is limited,” the clinic said in a statement June 9. (The study in question has not been peer-reviewed.)

“This is still a new virus, and more research is needed. It is important to keep in mind that this study was conducted in a population that was younger and healthier than the general population. In addition, we do not know how long the immune system will protect itself against re-infection after covid-19.” (Earlier in the interview, Hannity also said: “I believe in the science of vaccinations. ... I don’t want anyone dying from this thing. ... Also, talk to your doctor.”)

‘Some pretty serious side effects, including death’

We also previously fact-checked the second part of Johnson’s claim: “There is a risk to the vaccine. Again, it’s very small but there are some pretty serious side effects, including death. We are already over 5,200 deaths reported on the VAERS system.”

Johnson cited reports from the Vaccine Adverse Event Reporting System, a database co-managed by the CDC and the Food and Drug Administration, and he said death was a rare but possible effect of a coronavirus vaccination.

No study or case has established this. The VAERS database does not say coronavirus shots caused the reported deaths. Anyone can submit a report to VAERS; they are not verified. U.S. officials and experts make a point of saying that VAERS data should not be used to draw inferences such as Johnson’s and that federal agencies have other systems to monitor developing health risks tied to vaccines.

M. Miles Braun, a professor at the Georgetown University School of Medicine who served in public health positions at the CDC and FDA, previously told us this Johnson claim was a “misuse of the data.” Correlation by itself does not establish causation, he said.

“The kind of inferences he’s making, we really try to caution users not to use the data as he’s using it,” said Braun, who worked with the VAERS data for 13 years at the FDA.

Let’s pretend for a moment that the VAERS database does establish cause and effect. The death rate of 0.0018 percent from coronavirus vaccinations would be 1,000 times lower than the mortality rate from known cases of getting the disease (which is 1.8 percent in the United States).

The CDC says no evidence has established coronavirus vaccines as the cause of any death: “More than 334 million doses of COVID-19 vaccines were administered in the United States from Dec. 14, 2020, through July 12, 2021. During this time, VAERS received 6,079 reports of death (0.0018%) among people who received a COVID-19 vaccine. FDA requires health care providers to report any death after covid-19 vaccination to VAERS, even if it’s unclear whether the vaccine was the cause. Reports of adverse events to VAERS following vaccination, including deaths, do not necessarily mean that a vaccine caused a health problem. A review of available clinical information, including death certificates, autopsy, and medical records, has not established a causal link to COVID-19 vaccines. However, recent reports indicate a plausible causal relationship between the J&J/Janssen COVID-19 Vaccine and TTS, a rare and serious adverse event — blood clots with low platelets — which has caused deaths.”

As of May 12, more than 8.7 million shots of the single-dose Johnson & Johnson vaccine had been administered, 28 women who received it had developed TTS, and three of them had died, a CDC official said, adding that the benefits of the vaccine still outweighed the risk. A causal link between the vaccine and the deaths has not been established.

Henning sent us links to various local news reports from around the country documenting how some people died shortly after getting a coronavirus vaccine. Keep in mind: Nearly half of the U.S. population has been fully vaccinated against covid-19. Officials have not said the vaccine was the lone cause of death in any of the cases. In many of these news reports, doctors and family members of the deceased are quoted as saying that the cause of death could be unrelated.

In one case, a teacher who lived in El Paso and worked in Las Cruces, N.M., got vaccinated while he was positive for covid-19 and died. People who are positive for the disease should wait to get vaccinated until any symptoms clear and the requirements to stop isolating are met, the CDC says.

The Pinocchio Test

Johnson repeated two unscientific claims in this Fox News interview, but his phrasing went further than before when he said coronavirus vaccines come with the risk of “some pretty serious side effects, including death.”

He keeps disregarding scientists’ published findings about vaccine immunity and the clear guidance from federal health agencies and doctors. He failed to heed experts’ admonitions about his wrongheaded use of the VAERS data. His advisers have been unable to rebut, over the course of two months, the CDC’s assertion that currently “available clinical information, including death certificates, autopsy, and medical records, has not established a causal link to COVID-19 vaccines.”

We don’t know what motivates this one-man campaign of misinformation on a vital public health issue, but it’s clear this is a deliberate effort and not just a few stray comments.

Johnson earns Four Pinocchios. As we said in March, we intend to fact-check the senator whenever he makes false or misleading claims about this issue.

Four Pinocchios

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