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SciCheck’s COVID-19/Vaccination Project

No Scientific Basis for Vaccine ‘Shedding’ Claims

This article is available in both English and Español

SciCheck Digest

COVID-19 vaccines do not contain a live virus, so there isn’t a biological path for a vaccinated person to “shed” the SARS-CoV-2 spike protein to those around them. Nor is there any evidence the vaccines cause reproductive problems. That means there’s no basis for social media claims that “shedding” causes reproductive issues in unvaccinated people. 

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None of the COVID-19 vaccines used in the United States contains a live virus with the ability to reproduce itself. Therefore, there’s no scientific basis to support the claim that people who’ve received the authorized COVID-19 vaccines can spread or shed the virus to unvaccinated people.

Some vaccines, such as the rotavirus vaccine, use a weakened, or attenuated, “form of the germ that causes a disease” to “create a strong and long-lasting response,” as explained on the U.S. Department of Health & Human Services’ website. Infants who receive a rotavirus vaccine can shed the live virus, though it’s rare, potentially transmitting the virus and inducing immunity in those around them.

That’s not the case with the authorized COVID-19 vaccines. There is also no evidence that COVID-19 vaccines cause infertility. As we have written before, loss of fertility has not been reported among thousands of trial participants nor confirmed as an adverse event among millions who have been vaccinated.

Yet several online posts falsely claim that vaccinated people are “shedding” the SARS-CoV-2 spike protein, which is what the virus uses to enters cells, through their “breath” and “pores,” and that this is causing a number of reproductive problems in unvaccinated people.

In a video that has been viewed over 100,000 times and its accompanying blog post, herbal medicine author Dr. Cass Ingram falsely claims that the COVID-19 mRNA vaccines can “cause death and disease through GMO shedding.” 

Ingram goes on to say unvaccinated people are being exposed to “toxins” that cause sudden deaths, miscarriages, placenta dysfunctionality, “fist-sized blood clots” and menstrual cycle disorders just by “being around vaccinated people.” 

“There had been some fatalities from contact with the vaccinated. Now this does not mean hugging and kissing, necessarily. It means being in the same room, in the same elevator,” Ingram says on his video

But there is no biological path that would make shedding of the COVID-19 vaccines possible, experts tell us. 

“The COVID-19 vaccines currently authorized by the FDA are not live virus vaccines, and there is no medical or scientific evidence to suggest that COVID-19 vaccines shed,” Dr. Christopher M. Zahn, an obstetrician-gynecologist, retired Air Force officer and vice president of the American College of Obstetricians and Gynecologists, said in a statement sent to FactCheck.org. “This is a conspiracy that has been created to weaken trust in a series of vaccines that have been demonstrated in clinical trials to be safe and effective and that are our single best tool for confronting a global pandemic that has taken 600,000 lives in this country alone.”

Dr. Paul Offit, a co-inventor of the rotavirus vaccine and a member of the Food and Drug Administration’s Vaccines and Related Biological Products Advisory Committee, also told us it’s not possible for COVID-19 vaccines to shed live virus or the spike protein.

“It’s like asking me, do I think that if someone gets this vaccine that they could develop X-ray vision? No, I don’t think that’s possible,” Offit, director of the Vaccine Education Center at the Children’s Hospital of Philadelphia, said in a phone interview. “It’s never been shown to happen.”

The messenger RNA, or mRNA, vaccines produced by Pfizer/BioNTech and Moderna, and the adenovirus viral vector vaccine made by Johnson & Johnson, prompt the body, through different mechanisms, to produce one of the proteins of the SARS-CoV-2 virus called the spike protein.

“It’s just one protein, it’s not a virus,” Offit said. “It’s just one protein from the virus and all that protein does is induce antibodies against it, so you then make antibodies to that protein. That’s it. You don’t shed the protein, you don’t shed the antibodies, you just make antibodies to one protein. So it can’t possibly affect somebody else because proteins aren’t shed.” 

Live Virus vs. Protein

The distinction between a vaccine using a live virus and a vaccine that uses a harmless part of a virus, such as a protein, to trigger an immune response is important, Offit said. 

Photo by Juanmonino via Getty Images

Vaccines using a part of a virus to start a response, such as the spike protein produced by both the Pfizer/BioNTech and Moderna mRNA vaccines, cannot lead to the virus reproducing and shedding. The Johnson & Johnson vaccine is a viral vector vaccine. It uses a harmless adenovirus, modified so that it can’t replicate, to deliver instructions to cells to produce the spike protein, so the vaccine can’t lead to shedding either. But vaccines using a live virus can replicate and shed.

Offit said an example of a vaccine that sheds or creates what’s called contact immunity is the oral polio vaccine, which is no longer in use in the U.S. In that case, Offit said, people are given virus strains through the mouth; the virus then reproduces in the intestine and is shedded in the feces. Unvaccinated people pick up the virus from the vaccine mostly by touching things a vaccinated person had touched, especially if that person didn’t adequately wash their hands. 

Micaela Martinez, an infectious disease ecologist at Columbia University who has studied the history of polio, said indirect vaccination is usually a good thing. It “has been a really great thing for eradication initiatives,” she said, and it’s usually not harmful because it uses an attenuated virus, with very little or no capability to cause disease.

The only time it can be harmful, she said, is if the attenuated virus accumulates mutations that turn it back into its original form. But even then, she said, it wouldn’t cause adverse effects, such as fertility issues, that are outside of the pathology of the virus.  

Offit said other vaccines with live, weakened forms of virus —  such as the measles, mumps and rubella vaccine and the chicken pox or rotavirus vaccines —  also have the potential for shedding. But Martinez said, there’s not a lot of evidence that it actually happens. Shedding of a kind of flu vaccine, the live attenuated influenza vaccine or nasal spray flu vaccine, is common.

A newer kind of vaccine known as self-spreading vaccines, or self-disseminating vaccines, are currently used only in animals and also need a live virus or vector with the ability to reproduce. As we explained, that’s not the case with COVID-19 vaccines, contrary to what a viral post suggests

Martinez said that while the mRNA vaccines are a new vaccine technology, it doesn’t seem to be biologically feasible that they could lead to shedding, because the vaccines don’t have the capacity to prompt the body to build the full virus.

“I can’t see the biological path by which giving the vaccine would be able to generate any fully assembled virus that can then be replicating and then shed out into the environment,” Martinez said. “I’m not saying it’s not possible because these mRNA vaccines are very new. It’s not really clear to me as obvious a biological pathway that that could happen.” 

Pfizer: ‘The Vaccine Does Not Cause Shedding’

Several online posts falsely claim Pfizer “admits” that unvaccinated people can be environmentally exposed to the spike protein “by inhalation or skin contact” if in close proximity with vaccinated people. 

“Evidence that Pfizer knew about miscarriages from vaccines,” says Ingram in a separate post featuring an image of a Pfizer document.

That’s nonsense. 

It’s true that the Pfizer document, a clinical protocol to monitor safety and efficacy of its vaccine during the clinical trials, mentions “environmental exposure” to the vaccine during pregnancy via “inhalation or skin contact” or by exposure through a “male partner” or health care provider. 

But Martinez said the document only proves that Pfizer had a protocol in place in case environmental exposure happened, since environmental exposure does happen with some other vaccines and pregnancy is such a vulnerable time. 

“It’s laying out how they’re going to monitor to make sure that there aren’t dangerous exposures and shedding that happens that causes dangerous exposures to pregnant women,” she said.

But there was no environmental exposure to the Pfizer vaccine, according to the results of the clinical trial and the FDA’s review of Pfizer’s application for emergency use authorization. There were 23 pregnancies among the participants and no reported complications among the pregnant women who were vaccinated. (There was one spontaneous abortion to a woman given the placebo.)

“There was no mention in the emergencies authorization about the indirect exposures during pregnancy, which suggests to me that they had not found any,” Martinez said. 

A Pfizer spokesperson said the vaccine does not cause shedding because it is not a live virus. 

“The Pfizer-BioNTech COVID-19 vaccine is a synthetic mRNA vaccine and does not contain any virus particles. Because there is no virus produced in the body, no shedding occurs within the human body. The vaccine cannot be inhaled via shedding and can only enter the human body through an administered dose,” Pfizer said in a statement.

Who Is Dr. Ingram?

Ingram, who made these false shedding claims on his website cassingram.com, has a financial incentive for doing so. 

In his blog post, Ingram tells readers that one way of protecting against these dangerous “toxins” shedded by vaccinated people is to use “spice oil supplements such as oil of wild oregano or the multiple spice oil complex as well as the oregano oil/clove bud oil antiseptic spray,” some of which are sold through a company he has been associated with, North American Herb & Spice. 

“These spice oil-based formulas act to destroy the spike protein, halting the progression of the attack,” Ingram says in his post.

In 2008, North American Herb & Spice agreed to pay $2.5 million to settle charges by the Federal Trade Commission for falsely claiming its oregano oil and capsules were scientifically proven to prevent and treat colds and flu.

Judy Kay Gray, the founder and owner of North American Herb & Spice Co., and Ingram conducted research funded by her company on Oreganol P73 – one of the dietary supplements mentioned in the FTC complaint. In 2016, eVitamins identified Ingram as being “from North American Herb & Spice” during an interview on “some amazing benefits” of “their oregano products.”  

It’s unclear if Ingram is still associated with North American Herb & Spice. We could not reach him for comment. 

In a May 1 blog post on “protection against vaccine shedding,” Ingram includes a disclosure that says: “the author takes no paycheck or stocks for the recommendation of the mentioned foods or spices but for the book only. In that post, Ingram provides a link to a book he authored called “Foods that Cure,” which his blog post claims includes “effective remedies” for the “great toxicity” of COVID-19 vaccines.

On his website, Ingram also says he has “a D.O. from the University of Osteopathic Medicine and Health Sciences in Des Moines, IA (1984)” – which is the same university and graduating class as Cassim Igram, an osteopath who surrendered his license in Iowa 2019, according to the Iowa Board of Medicine. 

Cassim Igram, who practiced in Iowa and Illinois, also “voluntarily agreed to permanently and irrevocably place his license [in Illinois] on inactive status” in 1999 after being charged by the Illinois Department of Professional Regulation in 1997 for “[o]vercharging a set of two patients, along with their children,” according to court documents. Igram tried to restore his license in 2011, but the petition was dismissed

Ingram and Igram appear to be the same person, according to an investigation by the Chicago Tribune published in 2013. In addition to promoting herbal medicine remedies as Dr. Cass Ingram, Igram is also linked to a second pseudonym, Kaasem Khaleel or Dr. K., who promoted conspiracy theories, the Tribune said.

Editor’s note: SciCheck’s COVID-19/Vaccination Project is made possible by a grant from the Robert Wood Johnson Foundation. The foundation has no control over our editorial decisions, and the views expressed in our articles do not necessarily reflect the views of the foundation. The goal of the project is to increase exposure to accurate information about COVID-19 and vaccines, while decreasing the impact of misinformation.


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