Peter McCullough makes multiple false, misleading, and unsupported claims about COVID-19 vaccine safety and efficacy in viral podcast

The spike protein induced by COVID-19 vaccines is toxic and causes diseases and deaths; nattokinase can counter these effects
Incorrect: COVID-19 vaccines haven’t been shown to be toxic. “Detox” practices are unnecessary and their alleged effectiveness isn’t supported by scientific evidence.
Factually inaccurate: Large-scale trials show that COVID-19 vaccines don’t increase the risk of negative pregnancy outcomes and instead reduce pregnancy complications due to COVID-19.
Inadequate support: No evidence suggests a link between COVID-19 vaccines and a rise in deaths and medical conditions. Robust clinical trials showed no benefit of hydroxychloroquine and ivermectin treatment in COVID-19 patients.
All available evidence from clinical trials and safety monitoring indicates that the COVID-19 vaccines are safe and not associated with a rise in medical conditions and mortality. COVID-19 vaccines are also safe and recommended for pregnant women, who are at a higher risk of severe COVID-19 and pregnancy complications associated with the disease. Furthermore, COVID-19 vaccines haven’t been shown to be toxic, making so-called “detoxes” unnecessary.

FULL CLAIM: COVID-19 vaccines “are unsafe and they don’t have any theoretical benefit"; “the spike protein is toxic for the body”, it “causes heart damage, brain injury, blood clotting, neurologic injury” and pregnancy complications; "early treatments would have saved two thirds of the lives lost”


On 22 April 2023, the website X22 Report published a 27-minute podcast interview with cardiologist Peter McCullough. During the interview, McCullough referred to the COVID-19 vaccination campaign as a “worldwide debacle” and repeated previously debunked claims conveying the message that COVID-19 vaccines are ineffective and dangerous.

This isn’t the first time McCullough made such claims, as Health Feedback documented in earlier reviews. Also, the website that published the interview, X22 Report, is described by Media Bias Fact Check as a “strong Conspiracy and pseudoscience” source that often “promotes unproven claims”. In fact, the podcast was removed from YouTube and Spotify for its alleged links with the political conspiracy movement Qanon.

McCullough’s interview received over 350,000 views on the X22 Report website and on the video platforms Rumble and Bitchute, where it was also uploaded. Posts linking to the video gathered around 10,000 additional interactions on Facebook, according to social media analytics tool CrowdTangle.

Below, we will cover some central claims made by McCullough in the interview.

Claim 1 (Misleading):

“the vaccine was never tested to see if it reduced transmission”

Despite McCullough suggesting otherwise, there is nothing reproachable about the fact that Pfizer hadn’t tested the effectiveness of its COVID-19 vaccine against infection during initial clinical trials. Pfizer also didn’t conceal this fact, and the lack of information about the vaccine’s efficacy against infection and transmission was openly listed as a “remaining question” in the Research Summary of the study containing the trial results[1].

While a vaccine that blocks infection and transmission would be advantageous, it isn’t essential for the vaccine to be effective. In fact, most vaccines don’t prevent infection and have still proven highly useful in reducing disease, as Health Feedback explained before. Amid a pandemic that has caused almost seven million deaths worldwide, the main objective of the COVID-19 vaccine was to prevent severe illness, something that clinical trials showed the Pfizer-BioNTech COVID-19 vaccine to be highly effective at[1].

It is also important to note that even if a vaccine doesn’t block infection completely, it can still slow virus transmission, mostly by lowering the chances of the person getting infected in the first place. For example, COVID-19 vaccines highly reduced the likelihood of infection caused by the original variant[2]. In addition, studies evaluating household transmission suggest that the vaccines might also reduce infectiousness[3].

While the vaccine protection against infection and transmission dropped significantly due to waning vaccine immunity and the emergence of more transmissible variants[4], recent evidence suggests that it might not have faded completely.

For example, a study published in Nature Medicine in 2023 evaluated transmission in individuals from 35 California state prisons from December 2021 to May 2022, right when the Omicron variant emerged. The study found that those individuals who received at least one dose of a COVID-19 vaccine were 22% less likely to infect cellmates compared to unvaccinated inmates[5]. Booster doses and recent vaccination further reduced the likelihood of infecting others, highlighting the benefit of vaccination in reducing transmission within the community.

Claim 2 (Misleading):

“What makes [the virus] evolve over time is the inappropriate use of vaccines”; “in a setting of a highly prevalent illness the virus will find ways to become resistant to the vaccines”

Contrary to McCullough’s suggestion, virologists find no evidence indicating that COVID-19 vaccines have been major drivers in the evolution of SARS-CoV-2, as earlier reviews by Health Feedback and others explained.

Viruses evolve constantly, also in the absence of vaccination, through the accumulation of genetic changes called mutations that occur during the replication of the virus. Any pre-existing immunity in a population, either arising from vaccination or infection, adds a selective pressure that can further contribute to the evolution of the virus. But withholding vaccination wouldn’t prevent new variants from arising[6].

Every new infection gives the virus new chances to replicate and accumulate mutations, some of which can potentially lead to new variants. In periods when a virus circulates widely, causing many infections, the chance for new variants to emerge is higher.

COVID-19 vaccines are effective at preventing severe COVID-19, and as we explained above, they also reduce the likelihood of infection. Thus, vaccination reduces the opportunities for the virus to mutate and evolve into new variants. As the clinical virologist Siddharth Sridhar told fact-checking group Annie Lab, infection also reduces the likelihood of future infection. “The only difference is that vaccines help diminish death rates in this process,” Sridhar highlighted.

Claim 3 (Misleading):

“The original vaccines are pulled now because they are completely useless”; bivalent COVID-19 vaccines “failed in animal studies to stop the virus” and “no randomized trial has ever shown that they reduce the risk of hospitalization, death”

The original COVID-19 vaccines were monovalent, which means they targeted a single antigen—the spike protein of the initial SARS-CoV-2 strain. However, that initial strain was displaced by the more transmissible Omicron variants, whose spike protein differs from that of the initial strain due to mutations. These mutations improve the virus’ ability to evade previous immunity from both infection and vaccination.

On 31 August 2022, the U.S. Food and Drug Administration (FDA) authorized the bivalent COVID-19 vaccines from Moderna and Pfizer-BioNTech for use as booster doses. Instead of targeting a single antigen as the monovalent vaccines, bivalent formulations target the spike protein of the initial strain and that of the Omicron BA.4 and BA.5 variants.

On 18 April 2023, the FDA amended the authorization of the bivalent vaccines for use in people six months and older. At the same time, the agency announced that it no longer authorized the use of original monovalent vaccines.

Some, like McCullough, incorrectly interpreted this update to mean that the monovalent vaccines are “useless” or unsafe, which is false. Monovalent vaccines continue to be safe and effective against severe COVID-19. But as the FDA explained, the update intended “to simplify the vaccination schedule” using the best vaccine formulation available.

McCullough then claimed that the bivalent vaccines hadn’t been adequately tested in animals and clinical trials before being authorized. But this is again incorrect. As Health Feedback explained in this Insight article, the FDA based its authorization on multiple datasets. These included trial results for the original COVID-19 vaccines, which used the same technology and had a very similar composition to the bivalent vaccines. Using pre-existing data is a common approach in vaccine updates, like flu vaccine updates, that allows vaccine developers to respond to new emerging variants in a timely manner.

The other data that the FDA considered were the results from clinical trials evaluating earlier bivalent vaccines targeting the Omicron BA.1 variant with the exact same composition as the new bivalent vaccines and preliminary data in mice that received the BA.4/BA.5 bivalent formulation. All these studies sufficiently demonstrated that the bivalent vaccines are safe and generate a better immune response against Omicron variants compared to the original monovalent vaccines.

Claim 4 (Unsupported):

“the spike protein is produced for an uncontrolled duration and quantity of time, the spike protein is toxic for the body”

No scientific evidence supports McCullough’s claim that the spike protein exposure induced by COVID-19 vaccination is toxic, as Health Feedback explained in earlier reviews. As others did before, McCullough misinterpreted the results of studies that evaluated the effect of the viral spike protein, not the one induced by vaccination.

Indeed, early studies showed that high concentrations of the spike protein from the virus damaged blood vessels and heart cells cultured in the laboratory[7-9] and in animals[10]. But the spike protein from vaccination behaves differently from that of the virus and is also present in much lower amounts, which haven’t been shown to cause harm.

McCullough’s claim that the mRNA and spike protein from vaccination remain in the body for long periods also misrepresents the results of previous studies. One of the studies he cited was published by Ogata et al. in 2021[11]. This study found extremely low levels of spike protein in the blood of 11 out of 13 people one week after receiving the Moderna COVID-19 vaccine.

Another study was published by Castruita et al. in 2023 and found vaccine mRNA in the blood of 10 of the 108 individuals analyzed up to 28 days following vaccination. But it is important to note that all the individuals who participated in the study had chronic hepatitis C infection, and therefore might not be representative of the general population. Neither Castruita et al. nor Ogata et al. reported any detrimental effect associated with the presence of vaccine mRNA and vaccine-associated spike protein in people’s blood.

Speaking to the Vaccine Education Center at the Children’s Hospital of Philadelphia, pediatrician Hank Bernstein explained that mRNA has a very short life span, which prevents it from continuing to produce the spike protein. Within a few days after delivering the instructions to the cells, the mRNA is destroyed by the body. Likewise, the Infectious Disease Society of America estimated that the spike protein produced after vaccination lasts only for a few weeks before being destroyed.

Claim 5 (Unsupported):

“It’s a human disaster to have so many people take a brand new wildly experimental genetic vaccine, and now a recent survey shows that 15% of the people who took it have some new medical problem”

First of all, referring to COVID-19 vaccines as experimental is inaccurate, as Health Feedback explained in earlier reviews. COVID-19 vaccines demonstrated their safety and efficacy in large-scale clinical trials before being administered to the public and therefore aren’t experimental.

McCullough then linked the COVID-19 vaccines with “record rates” of cancer, heart damage, cardiac arrest, stroke, neurological impairment, blood clots different from anything seen before, and severe inflammatory symptoms, which he attributed to the toxicity of persistent spike protein from vaccination in the body. But as we explained above, there is no evidence indicating that the spike protein induced by vaccination is toxic, nor did McCullough produce any during the podcast.

Claims that COVID-19 vaccines are associated with a spike in these medical conditions are also unsubstantiated and were debunked by Health Feedback and other fact-checking organizations.

Like all medical interventions, COVID-19 vaccines carry some risk. Although rare, COVID-19 vaccines have been associated with some serious side effects. Viral vector-based vaccines (Janssen and AstraZeneca) have been associated with an extremely rare but life-threatening blood clotting disorder, while the mRNA COVID-19 vaccines (Pfizer-BioNTech and Moderna) are associated with heart inflammation in young males.

But these cases are very rare, and most common side effects of the COVID-19 vaccines are mild and last for only a few days. Furthermore, the risks of blood clotting and heart inflammation following vaccination are lower than that associated with COVID-19[12,13].

Claim 6 (Inaccurate):

“Vaccination in pregnancy is terribly dangerous too”

McCullough inaccurately linked COVID-19 vaccines with miscarriage, stillbirth, and adverse fetal outcomes. COVID-19 vaccine safety during pregnancy has been a frequent subject of misinformation, even after large studies showed that pregnant women who received a COVID-19 vaccine don’t have an increased rate of placental defects, miscarriages, and negative pregnancy outcomes[14,15].

On the contrary, pregnant women are at a higher risk of developing severe COVID-19, which in turn increases the risk of complications for both the mother and the developing baby. By preventing severe illness, COVID-19 vaccines reduce these risks[16]. For this reason, professional medical associations like the American College of Obstetricians and Gynecologists and public health agencies like the U.S. Centers for Disease Control and Prevention highly recommend that pregnant women get vaccinated against COVID-9.

Claim 7 (Unsupported and Misleading):

“Over half million Americans have lost their life with the vaccine”

It is unclear from the interview how McCullough arrived at this figure. Health Feedback reached out to McCullough for comment and will update this review if new information becomes available.

As a starting point for his calculations, McCullough cited “over 17,000 vaccine deaths” recorded by the U.S. CDC. Based on this figure and on the context provided during the rest of the interview, the 17,000 deaths might refer to the number of death reports in the U.S. Vaccine Adverse Event Reporting System (VAERS).

As of 2 May 2023, VAERS registered 19,476 preliminary reports of death among people who received a COVID-19 vaccine, a figure similar to that mentioned by McCullough.

However, VAERS reports simply show that an adverse event, such as death, occurred after receiving a vaccine. Therefore, VAERS reports “cannot be interpreted as evidence of a causal association between a vaccine and an adverse event” unless further evidence indicates that the vaccine caused or contributed to the adverse event.

Previous reviews by Health Feedback have documented how claims associating COVID-19 vaccines with deaths often misuse data from adverse event reporting systems like VAERS.

But there is no evidence suggesting that the COVID-19 vaccines caused a rise in mortality. While many countries have registered excess mortality over the past two years, there are multiple possible explanations for this excess that are more plausible and that don’t involve COVID-19 vaccines. explained in this fact-check that one of the most obvious reasons for the rise in excess deaths is COVID-19. Additional factors, such as the indirect effects of the pandemic on healthcare systems and other causes of death that were already increasing in the U.S., like drug overdose, likely also contributed to increased mortality[17].

Claim 8 (Unsupported):

Early treatment with drugs including hydroxychloroquine and ivermectin “would have saved two-thirds of the lives lost, two-thirds of the hospitalizations”; “they were undermined I believe for a reason, to advance the vaccine agenda”

Early laboratory studies evaluating the antimalarial medication hydroxychloroquine and ivermectin, a drug used to treat parasitic infections, showed promise. However, large, robust clinical trials found no benefit from either of these drugs in COVID-19 patients[18-21].

Therefore, contrary to McCullough’s claim, these drugs weren’t “undermined” to push COVID-19 vaccination but because the evidence suggested they were ineffective against COVID-19. In fact, the FDA authorized the emergency use of chloroquine and hydroxychloroquine in certain hospitalized COVID-19 patients in March 2020. However, the agency revoked it two months later, saying that “The totality of scientific evidence currently available indicate a lack of benefit”.

The growing body of negative results didn’t stop some individuals and anti-vaccine groups from promoting hydroxychloroquine and ivermectin for preventing and treating COVID-19, even after public health agencies warned against using these drugs for COVID-19.

Claim 9 (Incorrect and unsupported)

“Nattokinase effectively dissolves the spike protein”

After spending the interview enumerating the wide range of harmful effects that COVID-19 vaccines allegedly cause, McCullough talked about a dietary supplement supposedly capable of countering them all. This supplement contained nattokinase, an enzyme that was first isolated from a traditional Japanese dish called natto and made of fermented soybeans.

It is noteworthy that McCullough appears listed as the chief scientific officer of the company that sells the supplement, a conflict of interest that McCullough failed to mention during the interview.

Researchers found that nattokinase could break down certain proteins, like some proteins related to blood clotting, and dissolved blood clots in test tubes[22]. A 2022 study by Tanikawa et al. showed that nattokinase could also break down the spike protein of SARS-CoV-2 in test tubes[23], which McCullough cited to support his claim. However, test tubes don’t reproduce the complexity of a living organism, and these results don’t demonstrate that nattokinase eliminates the spike protein in people’s bodies.

But more importantly, the idea that one needs or can “detox” from vaccination is flawed. First, all vaccine ingredients follow rigorous assessments to ensure they are safe in the amounts present in the vaccines. Since COVID-19 vaccines don’t contain toxic ingredients, there is also no need to eliminate them from the body.


McCullough’s interview contained a series of inaccurate, unsupported, and misleading claims that conveyed the false message that the COVID-19 vaccines are ineffective and dangerous.

No evidence suggests that the spike protein induced by COVID-19 vaccination is toxic. McCullough’s claims that COVID-19 vaccines caused a rise in mortality and medical conditions are also unsupported by scientific evidence. Instead, studies show that COVID-19 vaccines are safe and effective at preventing severe COVID-19 and death.



Published on: 03 May 2023 | Editor:

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