It was inevitable that antivaxxers would claim that COVID-19 vaccines make females infertile

One of the most common false claims made by the antivaccine movement is that a vaccine (or vaccines in general) somehow result in female infertility. Sure, antivaxxers will sometimes promote the idea that vaccines cause sudden infant death syndrome (SIDS) or simply kill older children, but not nearly as often as they like to spread the persistent myth that vaccines somehow “sterilize” females. Examples abound and can be found around the world, for example, from the conspiracy theory promoted by Catholic bishops in Kenya that the tetanus vaccine is “racist population control” and that the false claim in Africa and the Philippines (among other places) that the polio vaccine can impair female fertility, while in some Muslim countries the campaign to eradicate polio has long been plagued by conspiracy theories that claim that the polio vaccine is laced with anti-fertility chemicals that would render their girls sterile before they even became women (and/or can also infect them with HIV) as part of a plot to depopulate the developing world. (Indeed, portraying vaccines as “eugenics” is a popular antivaccine trope.) Of course, the vaccine most commonly falsely cited by antivaxxers as causing female infertility is the HPV vaccine, particularly Gardasil, which is blamed without evidence for premature ovarian failure (now more commonly known as primary ovarian insufficiency), usually based on some hand waving misunderstanding of immunology attributing this “effect” to some vaguely defined autoimmune phenomenon. This claim that a specific vaccine (or vaccines) can cause infertility is what I like to refer to as a “slasher” lie, because, like the killers in 1980s slasher movies, who appear to have been finally killed at the end of one installment, these lies always manage to somehow survive to kill more teenagers in the next movie.

So it should come as no surprise that, with the rollout of the Pfizer/BioNTech vaccine against COVID-19 under an FDA emergency use authorization (EUA), with the vaccine by Moderna very likely to follow very soon in distribution, this old slasher lie has found new life, this time in the form of the claim that these two vaccines cause—surprise! surprise!—female infertility! Like the HPV vaccine before, it even has an alleged former pharmaceutical company employee at a high level fear mongering about the vaccine. (More on the details of that in a moment.) Before I go on to discuss this new bit of antivaccine disinformation and the conspiracy theory associated with it, let me just make a quick observation about how the antivaccine movement treats the genders differently. Notice how the lies about vaccines somehow causing infertility are basically always lies claiming that they cause female infertility. I can’t recall even a single antivaccine claim that vaccines impair male fertility. This is despite experimental vaccines existing for both female and male contraception (the former relying on beta-HCG like an experimental tetanus vaccine, the latter targeting sperm). I’m guessing claims about male infertility have probably been made, but, if so, they are far surpassed in number, imagination, and intensity by the claims that this vaccine or that somehow “sterilizes” females. That antivaxxers like to portray the HPV vaccine as the “promiscuity vaccine” and their obsession with vaccines supposedly rendering their women infertile, leads me to the conclusion that there is a lot of misogyny behind the antivaccine movement.

Dubious experts demand a stop to a clinical trial on the basis of nonsense

Let’s get back to the conspiracy theory that the new COVID-19 mRNA-based vaccines will cause female infertility. I guess it’s just one small step from using a total misunderstanding of the totality of molecular biology to claim that such vaccines will “reprogram your DNA” to finding a dubious “mechanism” by which they will render women infertile, and certainly antivaxxers have taken that step, as shown by this recent article entitled “Head of Pfizer Research: Covid Vaccine is Female Sterilization“. Interestingly, the actual content of the article is not nearly as definitive as the clickbait headline, but does report how two men have spread the claim that the new COVID-19 vaccines might cause female infertility. Seeing that article and various others making the same claim as the Pfizer vaccine is being loaded into trucks from the Pfizer plant in my home state of Michigan and being transported all around the country, I thought it a good time to examine this dangerous new form of an old antivaccine trope.

First, let’s look at a little history and comparison. Remember how the demonization of Gardasil used to cite an OB-GYN named Diane Harper, who was frequently represented as running the clinical trials of Gardasil used to obtain FDA approval when, as far as I was ever able to glean, all she did was to serve as principal investigator at one of the sites (site PI) where patients were being enrolled in the study? (She also said that she supports HPV vaccination.) Here, the conspiracy theory goes beyond that. Whereas Harper merely made comments that antivaxxers could interpret as being critical of the efficacy and safety of HPV vaccination, here the scientist is actually spearheading the conspiracy theory. I’m referring to Dr. Michael Yeadon, who is portrayed as the former head of respiratory research at Pfizer, and is working with a German doctor named Wolfgang Wodarg. Less than two weeks ago the two filed a motion for administrative and regulatory action to the European Medicines Agency (EMA), the EU agency responsible for EU-wide drug approval, warning that the vaccine can attack placenta cells, causing female infertility. Interestingly, the link to the PDF of the letter in the original article no longer works, but someone saved an incomplete version of the letter here and I found the complete 43-page letter here.

The letter doesn’t ask the EMA to stop the phase 3 trials of BNT162, the name for BioNTech’s mRNA-based COVID-19 vaccine developed with Pfizer just because it might cause infertility in females. There are a whole panoply of claims in the letter, some of which we’ve dealt with before. I won’t discuss them all, but I will briefly discuss Yeadon and Wodarg’s claim that the number of cycles for diagnosis of COVID-19 by PCR from nasal swab samples was set too high and therefore too sensitive. Because of the false positives, Yeadon and Wodarg claim that Sanger sequencing must be used to verify all the sequences. Sanger sequencing, for those not familiar with it, is an old method of sequencing DNA. In brief, Sanger sequencing was developed in 1977 by two-time Nobel Laureate Frederick Sanger and his colleagues. My first reaction upon reading the blog posts describing this particular demand was “WTF?” followed by: I know Sanger sequencing. I did Sanger sequencing when I was in graduate school back in the 1990s. My wife’s job when she worked at a biotech company back in the early 1990s was Sanger sequencing. It’s laborious and time consuming and requires a lot of starting material compared to PCR. (Does anyone remember how hard it was to pour sequencing gels?)

Then I got out of my time warp and realized that, of course, technology has marched on since the 1990s and Sanger sequencing can now be used in conjunction with various DNA sequencing machine technologies. Even so, what Yeadon and Wodarg propose is unnecessary and impractical:

All RT-qPCR-positive test results used to categorize patient as “COVID-19 cases” in the trials and used to qualify the trial’s endpoints should be verified by Sanger sequencing to confirm that the tested samples in fact contain a unique SARS-CoV-2 genomic RNA. Congruent with FDA and EMA requirements for a confirmed diagnosis of human papillomavirus (HPV) using PCR, the sequencing electropherogram must show a minimum of 100 contiguous bases matching the reference sequence with an Expected Value (E Value) <10-30 for the specific SARS-CoV-2 gene sequence based on a BLAST search of the GenBank database (aka NCBI Nucleotide database).

Basically, this, like the “casedemic” claim, is a strategy to cast doubt on the accuracy and utility of reverse transcriptase real-time PCR to diagnose COVID-19 infection. The point is, once you’ve optimized the PCR conditions and demonstrated again and again that the PCR product you are getting is, in fact, the nucleotide sequence your PCR primers were intended to target, it is wasteful and unnecessary to demonstrate that for each and every sample. Indeed, in general, such validation is only performed when there is reason to doubt that the PCR reaction is working correctly, as when the PCR product is the wrong size, for instance. I thus realized that the point of this particular demand was nothing more than to cast doubt on PCR diagnosis of COVID-19 and to add a lot of unnecessary time and expense to the diagnostic testing end of the clinical trial, particularly when one of the endpoints is also symptomatic disease.

I also can’t help but note, to conclude this section, that one of the Exhibits that Yeadon and Wodarg cites is written by Sin Hang Lee. Regular readers of this blog might remember that Lee is a pathologist who made a name for himself nearly a decade ago when he was hired by the antivaccine group SANE Vax to use ultra-sensitive nested PCR to find—gasp!—HPV DNA in Gardasil, a meaningless finding that antivaccine groups ran with, producing dubious claims of “microcompetition” by the DNA to cause autoimmune disease, including primary ovarian insufficiency, and even death, as when Dr. Lee teamed up with antivaccine “scientist” Christopher Shaw and used highly dubious PCR methodology to try to convince an inquest in New Zealand that DNA fragments from Gardasil had caused a young woman’s death. Truly, antivaccine cranks never go away. They just keep showing up in different forums arguing different nonsense.

Oh, no! The Pfizer/BioNTech vaccine is coming for our women!

Interestingly, the claim that the Pfizer/BioNTech vaccine could potentially cause infertility is actually a small part of the overall petition, which spends far more verbiage on PCR, Sanger sequencing, and the not-unreasonable but thus far not observed concern about antibody-dependent enhancement (ADE) due to a vaccine, which has been a problem in the development of vaccines against Dengue Virus, Ebola Virus, HIV, RSV, and the family of coronaviruses. Basically, ADE is a phenomenon where a subject who has antibodies to a disease can mount a hyperactive immune response to it if challenged again. ADE has been observed in animal models of coronavirus vaccines in the past, for example, against SARS, but thus far not observed in humans in trials of vaccines directed against the spike protein of SARS-CoV-2, the coronavirus that causes COVID-19. Given the number of subjects thus far vaccinated, if ADE were a problem we’d expect to have seen it by now.

Let’s get to the key claim made by Yeadon and Wodarg regarding the COVID-19 vaccine and female infertility, as described in the original blog post that went viral and started the social media spread of this particular claim:

The vaccinations are expected to produce antibodies against spike proteins of SARS-CoV-2. However, spike proteins also contain syncytin-homologous proteins, which are essential for the formation of the placenta in mammals such as humans. It must be absolutely ruled out that a vaccine against SARS-CoV-2 could trigger an immune reaction against syncytin-1, as otherwise infertility of indefinite duration could result in vaccinated women.

From the petition itself:

Several vaccine candidates are expected to induce the formation of humoral antibodies against spike proteins of SARS-CoV-2. Syncytin-1 (see Gallaher, B., “Response to nCoV2019 Against Backdrop of Endogenous Retroviruses” – http://virological.org/t/response-to-ncov2019- against-backdrop-of-endogenous-retroviruses/396), which is derived from human endogenous retroviruses (HERV) and is responsible for the development of a placenta in mammals and humans and is therefore an essential prerequisite for a successful pregnancy, is also found in homologous form in the spike proteins of SARS viruses. There is no indication whether antibodies against spike proteins of SARS viruses would also act like anti-Syncytin-1 antibodies. However, if this were to be the case this would then also prevent the formation of a placenta which would result in vaccinated women essentially becoming infertile. To my knowledge, Pfizer/BioNTech has yet to release any samples of written materials provided to patients, so it is unclear what, if any, information regarding (potential) fertility-specific risks caused by antibodies is included.

According to section 10.4.2 of the Pfizer/BioNTech trial protocol, a woman of childbearing potential (WOCBP) is eligible to participate if she is not pregnant or breastfeeding, and is using an acceptable contraceptive method as described in the trial protocol during the intervention period (for a minimum of 28 days after the last dose of study intervention).

This means that it could take a relatively long time before a noticeable number of cases of postvaccination infertility could be observed.

Perhaps the most convincing counterargument to this is simple, but I will go beyond that to go into the weeds a bit. First, however, the simple counterargument:

Humans do have a protein called syncytin-1, which is critical in developing the placenta during pregnancy, Stockwell said in an email. “Theoretically, an immune response against this protein could cause increased risk of a failed pregnancy.”

But if the claims in the blog post were accurate, that would mean that pregnant women who catch COVID-19 would also become infertile, he said. No increased infertility or pregnancy loss has been observed in women with COVID-19.

Exactly. But what about the claim that syncytin-1 is so similar to the COVID-19 spike protein that a vaccine using the spike protein to provoke an immune response against SARS-CoV-2 would risk cross reacting with syncytin-1? Just as I was gearing up to do a bunch of BLAST searches against the Genbank database, as I did so many months ago when James Lyons-Weiler was making claims that SARS-CoV-2 (then called 2019-nCoV, so long ago was it) was created in a lab, I came across an excellent post by Edward Nirenberg, where, in order to answer the question of how much the SARS-CoV-2 spike protein resembles syncytin-1, he did the same BLAST searches I was gearing up to do. Basically, being the sometimes-lazy guy that I am, I thought: Why should I reinvent the wheel? I’ll just cite him instead! First, I’ll note that he also provided an excellent description of what syncytins are:

Did you know that the reason that eutherians (placental mammals) have a placenta is because of several retrovirus infections? They gave us proteins called syncytins, which form a structure called a syncytium or polykaryon (literally “many kernels,” where kernel is an old word for “nucleus”) if you’re fancy… syncytium is essentially one giant cell that contains the nuclei of many cells. Your muscle cells are syncytia (that’s the plural for syncytium), for example, and syncytia are common cytopathic effects one can observe when cell cultures are infected with some viruses. Genetic studies of mice in which syncytins are knocked out (mutations are introduced so that no functional protein is generated) show that syncytins are critical for the formation of a placenta, and in their absence it fails to form. In humans, there are two proteins responsible for this: syncytin-1 (present in every layer of the trophoblast, the outer layer of cells in the blastocyst, a very early point in the development of a mammal appearing between days 5 and 9) and syncytin-2 (found in cytotrophoblast cells). The placenta is required for pregnancy, and thus tampering with syncytins can result in infertility.

Nirenberg, like Stockwell quoted above, also notes that there is no evidence that COVID-19 infection predisposes to early pregnancy loss, and he even cites the peer-reviewed literature. Read more if you’re interested in that aspect. In the meantime, I’ll note that Nirenberg also points out vaccines using only the receptor-binding domain of the spike protein (Moderna) rather than the entire spike protein, shouldn’t have any sequence homology between syncytins and the spike protein, because the receptor-binding domain is not the region of the protein that mediates viral fusion. Expected results aside, it’s a simple matter to take the amino acid sequence of the SARS-CoV-2 spike protein and use the Basic Local Alignment Search Tool (BLAST) to compare it to the proteins encoded by the human genome. Nirenberg did just that, and found that “no human sequences align, but there is exceptional homology with many other SARS-CoV-2 isolates”.

Amusingly, Nirenberg also notes that there is actually a nine amino acid sequence “with 66% sequence identity between syncytin-1 and SARS-CoV-2 spike, which somehow the author of this claim ignored, even though this would represent a (still untenable but nonetheless) greater risk for autoimmune disease than the short stretch of sequences present there,” further twisting the knife by noting that he mentions “this to point out the competence of the individual behind the claim only”. I do so love pointing out something a crank missed as evidence for his incompetence, and that’s what Nirenberg did.

My enjoyment aside, such a small stretch of sequence homology (similarity) tends to be missed on BLAST because it “does not represent a significant homology, and similarly, it’s not going to be a concern for your immune system.” Bending over backwards to be fair, Nirenberg further goes on to mention in an addendum that, yes, it’s possible that how proteins fold might represent a means of even small bits of the protein being similar enough to provoke a B-cell immune response through molecular mimicry, but then shoots that claim down:

BLAST does not allow for considerations of how proteins fold, and thus cannot model B cell epitopes effectively. A rigorous approach to the question of whether or not molecular mimicry were possible here is actually a fairly advanced bioinformatics project that might merit a publication because one would have to be able to model how the proteins folded in space to see if conformational epitopes were shared (in the case of B cells), where the endogenous antigen presentation machinery is likely to make cuts in processing the spike protein antigen, determine which epitopes would be immunodominant, compare this to known HLA alleles to see if there are specific binding clefts that fit putatively cross-reactive sequences very well to see if a genetic susceptibility exists (assuming a cross-reactive sequence is identified in the first place), and then you would eventually need in vivo validation that this is legitimate (but that comes after all the very heavy bioinformatics work).

So, why did I go with a BLAST search, knowing these deficiencies? Was I being willfully dishonest? Well, no. BLAST will miss very short identities, like the 8-12 amino acids needed to share a T cell epitope. However, if BLAST did identify a significant sequence identity, that could be cause for concern, it would be a good indicator for further investigation, and thus I felt it was a reasonable shortcut rather than undertaking the complex bioinformatics project I described above, taken together with the available epidemiologic data. I will add though that if a competent bioinformatician wants to undertake the previously aforementioned project, I would be happy to update this post with their findings and credit them fully. The presence of a shared (putative- as it’s not known that this sequence could even end up being presented by antigen-presentation machinery without much more complex analysis) T cell epitope alone does not allow for autoimmune disease- a litany of other conditions must be fulfilled before this can be seriously considered (we still have an extensive suite of immunologic tolerance mechanisms).

He further cites this excellent Twitter thread in which an immunologist named Andrew Croxford does an exercise in which he takes the peptide sequence of the spike protein and aligns it with random human protein sequences.

He puts a bow on the whole thread by pointing out the inconsistency in Yeadon and Wodarg’s “hypothesis” (if you can call it that):

Basically, the stretch of amino acid similarity between the spike protein of SARS-CoV-2 and syncytin-1 are too short to be of any immunologic consequence. Moreover:

To summarize, I quote Edward Nirenberg’s “short version”:

Someone has claimed that the COVID-19 vaccines are going to cause infertility because of a shared amino acid sequence in the spike protein of SARS-CoV-2 and a placental protein, which will make the immune system attack both as it can’t tell the difference. The truth? This sequence is too short for the immune system to meaningfully confuse it with placental proteins. It’s sort of like saying that you are going to be confused with a criminal because you wear a commonly sold red bracelet that was also found on the criminal. It’s not realistic. If this were true, we would also expect COVID-19 to cause early pregnancy loss a significant amount of the time. The evidence available to us does not support that this is the case. There is no reasonable basis to believe that vaccines against COVID-19/SARS-CoV-2 will affect fertility.

Whenever I see disinformation like this, I’m always interested in who is spreading it.

Who are Michael Yeadon and Wolfgang Wodarg?

Having never heard of either member of this not-so-dynamic duo of physicians and scientists before, I naturally wondered who they were. Michael Yeadon was fairly easy to look into in that news stories mentioned, that, yes, he did work for Pfizer until 2011. His LinkedIn profile lists him as having had multiple titles at Pfizer:

• Chief Scientific Officer (CSO), Allergy and Respiratory Research, 1995-2011
• Vice President, Allergy & Respiratory Head, Research, 2005-2008
• CSO and VP, Allergy & Respiratory Research Head, 2006-2011

I can’t help but also note that some of the news stories I read described trying to verify his previous employment at Pfizer but having failed.

It doesn’t matter, though. Let’s assume that Dr. Yeadon’s employment history with Pfizer is as he says. A simple search on his name reveals that this isn’t his first rodeo when it comes to dubious science. In fact, I didn’t notice the first time I saw the viral blog post, but Yeadon has been featured on über-quack Joe Mercola’s website before making false claims about COVID-19:

Like several other scientists, doctors and researchers, Yeadon has pointed out that there are no excess deaths due to COVID-19.2,3,4 According to Yeadon, who has analyzed the statistics, about 1,700 people die each day in the U.K. in any given year. Many of these deaths are now falsely attributed to COVID-19.

“I’m calling out the statistics, and even the claim that there is an ongoing pandemic, as false,” he said in a recent interview with British journalist Anna Brees (see video above). He challenges anyone who doesn’t believe him to seek out any database on total mortality. If you do that, you will find that the daily death count is “absolutely bang-on normal,” Yeadon said.

Like Hodkinson, Yeadon is concerned about the fact that the laws of immunology are being completely ignored — apparently in order to fit some hidden agenda.

While Yeadon is unwilling to guess at what might be behind the creation of these false narratives, or why scientific truth is being censored, others have linked together evidence pointing to the pandemic being used as an excuse for the redistribution of wealth and the technocratic takeover of the whole world under the banner of a “Great Reset.”

First, it’s not true that there isn’t a lot of excess mortality in the UK due to COVID-19. Second, it’s obvious that Yeadon is a card-carrying, full-blown conspiracy theorist. For those who haven’t heard of it, the “Great Reset” is a proposal by the World Economic Forum that’s launched a major conspiracy theory claiming that the COVID-19 pandemic is being used as a pretext whose purpose is to “usher in a tech-driven dystopia free of democratic controls” and create a “new ‘social contract’ that ties you to it through an electronic ID linked to your bank account and health records, and a ‘social credit’ ID that will dictate every facet of your life”. Regardless of the merits of or problems with the proposal itself, the “Great Reset” is a horrible name. It’s almost as though the World Economic Forum wanted to provide the perfect fodder for conspiracy theorists, and I’d love to talk to whoever thought that name was a good idea. (Anyone who pays attention to conspiracy theorists could have told them that the very name would turn into a conspiracy theory!) My irritation with a horrible name aside, it’s no wonder that Yeadon also features prominently in the “casedemic” conspiracy theory that claims that the count threshold for PCR testing for COVID-19 is intentionally being set too high (i.e., too sensitive) and that PCR testing can’t tell if you have COVID-19 and has been featured by Mercola on more than one occasion, never a good look if you are truly science-based. Indeed, if Yeadon were truly science-based in his concerns, he’d avoid Mercola like the quack plague that he is.

He’d also avoid the American Institute for Economic Research (AIER), the right-wing propagandists disguised as a “think tank” behind the eugenics-adjacent Great Barrington Declaration that basically advocates letting COVID-19 rip through the “young and healthy” population (because, you know, it’s harmless to them) while using “focused protection” to protect the elderly and those vulnerable to severe disease due to their chronic illnesses. Never mind that it’s impossible to protect the elderly and vulnerable from a virus that’s spreading unchecked everywhere else. Unsurprisingly, Yeadon not only doesn’t avoid AIER – he’s appeared in a video for the group asking why health authorities won’t declare the pandemic to be over. No, seriously.

If you don’t believe that Yeadon is a COVID-19 denialist and conspiracy theorist, a quick perusal of his Twitter feed will disabuse you of that notion:

I got tired of finding such Tweets, and I only went back four days.

What about Wolfgang Wodarg? He’s a German physician and politician, a member of the Social Democratic Party, who was elected to the Bundestag in 1994 and remained there for 15 years. One thing I found very rapidly is that, whatever his qualifications otherwise, COVID-19 is not his first rodeo when it comes to bad science and denying severity of a pandemic. It turns out that he did a similar thing during the H1N1 pandemic of 2009-2010 when he testified at a hearing conducted by the Council of Europe’s Committee on Social, Health and Family Affairs. The theme? “False pandemics: a threat to health”. Yes, that’s right:

At today’s hearing, several committee members pressed the WHO and vaccine company officials on two main issues. They expressed deep suspicions that vaccine industry experts on WHO advisory groups improperly influenced the WHO’s assessment of the pandemic in order to financially benefit pharmaceutical companies. Council members also questioned the WHO official, Dr Keiji Fukuda, special advisor on pandemic influenza to the WHO director-general, about confusion surrounding consideration of severity in its definition of a pandemic, which was revised at about the time the novel H1N1 virus was identified.

Some government public health officials and influenza experts have strongly rejected Wodarg’s claims, defending vaccine stockpiling as a prudent public health response and calling the charges “preposterous.”

In his opening statement, Wodarg said he was skeptical about the threat of the H5N1 virus and the contracts that countries had in place with vaccine makers in the event of a pandemic. “WHO had the trigger,” he said, alluding to the pandemic plans of some countries that activate the contracts when the WHO declares the highest alert level. He speculated that vaccine makers are making a financial windfall from what he claims are more expensive patented and adjuvanted vaccines. He also argued that the billions that governments have spent on pandemic vaccines could be better spent on other health issues.

He charged that the change in pandemic definition “made it possible to turn a run-of-the-mill flu into a pandemic and translate into millions for vaccine for no good reason.”

Wodarg also claimed that adjuvanted vaccines used in Europe were not adequately tested, especially in children, and expressed doubts about the safety of cell-based pandemic vaccines.

Sound familiar? In 2010, Wodarg described H1N1 as a “run-of-the-mill flu” that the WHO and EU turned into a “pandemic”, all in order to produce huge profits for vaccine companies. In 2020, he’s describing COVID-19 as not nearly as prevalent or serious because of PCR false positives, something done—you guessed it!—to lead to huge profits for vaccine companies. Meanwhile, back in March, in a video in German with English subtitles, Wodarg was trying to convince people that COVID-19 was no more dangerous than the flu as he claimed that the virus “is not new” but merely another harmless coronavirus. He also referred to the pandemic as “alleged” and concluded, “The king is wearing no clothes”.

Same as it ever was. Cranks gonna crank, and quacks gonna quack. The sad thing is that this not-so-dynamic duo is stoking real fear that the new COVID-19 vaccines will make women infertile and is doing it based on speculative nonsense. Truly, antivaccine tropes never, ever die, which is why it was inevitable that the claim that COVID-19 vaccines will endanger female fertility would make an appearance before the vaccines were approved. Think of this as Jason Voorhees or Michael Myers appearing to die at the end of a movie, only to reappear in a subsequent installment of the series to kill again. Slasher lie, indeed.