Did 60 Lab Studies Recently Confirm a Cancer Link to a Vaccine You Had as a Child?

An attention-grabbing headline mischaracterized actual polio vaccine contamination in the 1950s and 60s as an issue relevant to today’s vaccines.

Published July 17, 2018

 (Rido / Shutterstock)
Image courtesy of Rido / Shutterstock
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On 28 May 2018, Erin Elizabeth’s clickbait medical conspiracy blog “Health Nut News” published an article under the chilling headline "60 Lab Studies Now Confirm Cancer Link to a Vaccine You Probably Had as a Child."

Although the use of the word “now” implied a certain immediacy to the news, the “Health Nut News” article was a word-for-word copy of one published by Dr. Mercola, Elizabeth’s partner, seven years earlier. This report was not a breaking news story, but rather a rehashed recounting of the factual existence of polio vaccine contamination in the 1950s and 60s, seemingly intended to instill doubt about the safety and efficacy of present-day vaccines.

Despite the headline's reference to a vaccine readers "probably had as a child" (i.e. a potentially contaminated polio vaccine given in the 1950s and 1960s), much of the article itself was about lambasting the HPV vaccine Gardasil, which was not approved until 2009 and has no connection to the polio vaccine (save for the obvious fact that both are vaccines). The year 2011, when the original Mercola version of the story was published, coincided with multiple controversies related to HPV vaccination as well as its politically charged FDA approval for use in boys — aspects mentioned derisively in the Mercola piece. This dubious article's republication in 2018 seemed to be little more than the pushing out of non-relevant clickbait aimed at expanding Health Nut News’ social media presence.

Mercola opened his 2011 article with an amateurish and poorly edited YouTube video of a “censored” portion of an interview with noted vaccine pioneer Maurice Hilleman. In the video, Hilleman discussed his discovery (which was in no way “censored”) of the polio vaccine's being contaminated by the SV40 simian (monkey) virus when it was first released. That discovery led to a long and contentious scientific debate over the notion that the SV40 virus had a causal link to some cancers, an idea largely abandoned by modern researchers.

The Polio Vaccine and Simian Virus 40

Between 1955 and 1962, some samples of the polio vaccine injection were, in the U.S. and many other countries, contaminated with a monkey-derived virus given the name SV40 (for Simian Virus 40). At the time, these vaccines had been produced by growing the polio virus on a cell line derived from African green monkey kidney cells, which in some cases (it was later discovered) were contaminated with SV40:

In 1960, SV40 was discovered as a frequent infection of monkeys and contaminant of harvested kidney tissue, which was used to grow poliovirus vaccine stocks. During the period from 1955, when poliovirus vaccines were first administered in public health campaigns, until 1963, when the vaccine in use was free of SV40, it is estimated that tens of millions of people in the USA and other countries received SV40-contaminated poliovirus vaccines.

This discovery led to concern and speculation that the virus, though specific to monkeys, could be a cause of some cancers in humans. Laboratory studies on mice, as well as epidemiologic studies conducted decades later, hinted at an association between SV40 and some cancers, and SV40 DNA has been found in some tumors. A 2002 National Academies review of the subject determined not enough data existed to establish a causal link, while a large-scale expert review in 2005 concluded that such a link was unlikely: "The epidemiologic studies of vaccine recipients offer ... a somewhat reassuring public health message, namely, that contamination of vaccines with SV40 did not lead to a measurable increase in cancer risk."

The Mercola/Health Nut Spin

While spending most of his article railing against other vaccines, Mercola attempted to make the issue of polio vaccine contamination seem relevant to a much larger period of time than reality would justify. In his piece, Mercola claimed that:

For years, researchers suggested that millions of vials of polio vaccine, contaminated with SV40, infected individuals between 1953 and 1963 and caused human tumors, and by 1999, molecular evidence of SV40 infections were showing up in children born after 1982. Some experts now suggest the virus may have remained in the polio vaccine until as late as 1999.

The link documenting Mercola's claim of SV40 infections occurring in children born after 1982 was meant (according to the URL listed) to point to a 2008 article on titled “Simian Virus 40 DNA Found in U.S. Children.” Instead, that page now redirects to a 2014 article about adverse reactions to vaccines that does not once mention polio or simian viruses.

Although some evidence suggests that people born far after the polio contamination years were infected with the SV40 virus, later research has demonstrated that the virus can be transmitted between humans through means other than contaminated vaccines.

Perhaps the most inflammatory claim in Mercola's article, that the polio vaccine may have been contaminated as recently as 1999, is also the one least supported by scientific data. The article's source for this assertion was a link to a paper once housed on a now-abandoned website with the domain name Based on contextual clues, the paper Mercola and Health Nut News were trying to point to was a 2000 paper published in the journal Anticancer Research and written by a lawyer named Stanley Paul Kops, who (at least when he was in practice) appears to have made a living by suing the government and pharmaceutical companies over alleged SV40-caused cancer.

That paper’s argument was not a scientific one. Instead, it offered the claim that the manufacturer of one of the oral polio vaccines did not adequately test their manufacturing materials for contamination, leaving open the possibility that more recent vaccinations were also contaminated — a claim that facilitated the author's continuing to file lawsuits. The paper provided no affirmative evidence in favor of the author's main assertion, merely suggesting instead that “outside scientific and independent researchers” should look into the subject.

The Broader Point

To read a Mercola article is to take an ambling walk through a forest full of fascinating features and forget, ultimately, why you began your stroll through the woods in the first place. The reason for this walk, lest we forget, was to see evidence that 60 laboratory studies now link a vaccine you took as a child to cancer. If you received the polio vaccine between 1955 and 1962 (i.e., you are between 56 and 63 years old), it is possible you were exposed to SV40 — that point is neither controversial nor new, and probably well over “60 studies” cover that subject.

We asked Elizabeth which 60 studies her headline referred to, and why that number had not changed between the related article's initial publication by her partner in 2011 and her own republication of it in 2018, but we received no response. The most current research suggests that although an SV40 polio vaccine contamination did take place several decades ago, that event did not lead to an increased risk of cancer for the people who received the vaccine at the time. Nonetheless, Mercola used the existence of that controversy to encourage mistrust of all vaccines up to the present day, averring that “With all the uncertainty surrounding the safety and efficacy of vaccines, it’s critical to protect your right to make independent health choices."

A great deal of that “uncertainty,” it should be noted, comes from context-free, fact-challenged articles that seek to alarm rather than inform — and thereby garner more click-throughs than sober, well-reasoned reports with non-sensational headlines.

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Elizabeth, Erin.   "60 Lab Studies Now Confirm Cancer Link to a Vaccine You Probably Had as a Child."     Health Nut News.   28 May 2018.

Mercola, Joseph.   "60 Lab Studies Now Confirm Cancer Link to a Vaccine You Probably Had as a Child."   18 February 2011.

Sweet, B. H. et al.   "The Vacuolating Virus, S.V.40."     Experimental Biology and Medicine.   1 November 1960.

Engles, E.A.   "Cancer Risk Associated with Receipt of Vaccines Contaminated With Simian Virus 40: Epidemiologic Research."     Expert Reviews Vaccines.   April 2005.

Stratton, K. et al.   "Immunization Safety Review: SV40 Contamination of Polio Vaccine and Cancer."     National Academies Press.   2002.

Taronna, Angelo.   "Serological Evidence of an Early Seroconversion to Simian Virus 40 in Healthy Children and Adolescents."     Plos One.   25 April 2013.

Kops, S.P..   "Oral Polio Vaccine and Human Cancer: A Reassessment of Sv40 as a Contaminant Based Upon Legal Documents."     Anticancer Research.   November 2000.

Alex Kasprak is an investigative journalist and science writer reporting on scientific misinformation, online fraud, and financial crime.