Stop me if you’ve heard this before – another anti-HPV vaccine paper gets retracted. Yeah, I’ve written about these retractions so many times (here, here, and here, and that’s just a sample), I could publish a book just about these “researchers.” And now we here about another anti-vaccine study, that was recently retracted, which claimed that the HPV vaccine caused neurological damages. This study heads to the dustbin of scientific research, as it deserves.
A mountain of high quality, robust clinical and epidemiological evidence has overwhelmingly established that the HPV vaccine is safe and effective. This is approaching the level of settled science.
With the retraction of the study that the HPV vaccine caused neurological damage, it’s clear that the anti-vaccine crowd has almost nothing to support their hatred of the vaccine. Not that it will stop them.
All about HPV vaccines
Many of you have read this section an enormous number of times, however, for some of the readers of this blog, this article might be their first bit of research into the human papillomavirus (HPV) vaccine. I feel it is important to a new reader to review the facts behind the human papillomavirus, the HPV vaccines, and HPV-related cancers. This section is constantly updated for even regular readers, but you can skip ahead if you know all of this.
Genital and oral HPV infections are the most common sexually transmitted infections (STI) in the USA. HPV is generally transmitted from personal contact during vaginal, anal or oral sex.
It’s important to note that there are more than 150 strains or subtypes of HPV that can infect humans – however, only 40 of these strains are linked to one or more different cancers. Although the early symptoms of HPV infections aren’t serious and many HPV infections resolve themselves without long-term harm, HPV infections are causally linked to many types of cancers in men and women. According to current medical research, here are some of the cancers that are linked to HPV:
These are all dangerous and disfiguring cancers that can be mostly prevented by the HPV cancer vaccine. If you’re a male, and you think that these are mostly female cancers, penile cancer can lead to amputation of your penis. Just think about that guys.
There is also some fairly strong evidence that HPV infections might be linked to prostate and some skin cancers, which would vastly increase the number of HPV-related cancers diagnosed every year. The HPV vaccine could be one of the best prevention tools for cancer we’ve ever found.
HPV is believed to cause nearly 5% of all new cancers across the world, making it almost as dangerous as tobacco in that respect. According to the CDC, roughly 79 million Americans are infected with HPV – approximately 14 million Americans contract a new HPV every year. Most individuals don’t even know they have the infection until the onset of cancer. The CDC also states that over 31,000 HPV-related cancers are diagnosed in the USA every year.
There were two HPV vaccines on the world market before 2014. GSK, also known as GlaxoSmithKline manufactured Cervarix, a bivalent (protects against two HPV strains) vaccine. It has been withdrawn from the US market (although available in many other markets), because of the competition from the quadrivalent (immunizes against four different HPV strains) and 9-valent (against nine HPV strains) Gardasil vaccines.
Merck manufactures Gardasil, probably the most popular HPV vaccine in the world. The first version of the vaccine, quadrivalent Gardasil, targets the two HPV genotypes known to cause about 70% of cervical cancer and two other HPV genotypes that cause genital warts. In Europe and other markets, Gardasil is known as Silgard.
The newer Gardasil 9, approved by the FDA in 2014, is a 9-valent vaccine, protecting against HPV Types 6, 11, 16, 18, 31, 33, 45, 52, and 58. It targets the four HPV strains found in the quadrivalent version, along with five additional ones that are linked to cervical and other HPV-related cancers. Both versions of Gardasil are prophylactic, meant to be given to females or males before they become exposed to possible HPV infection through intimate contact.
Gardasil is one of the easiest and best ways to prevent a few deadly cancers that are related to HPV. It is definitely a cancer-preventing vaccine.
(Just a quick note. There are actually two cancer-preventing vaccines. Along with the HPV vaccines, the hepatitis B vaccine is also important for the prevention of some cancers. The vaccine prevents hepatitis B viral infections. Chronic hepatitis B infections can lead to liver cirrhosis or cancer. Liver cancer is actually one of the few cancers in the USA where the incidence has increased over the past few years. And if you follow the anti-vaccine rhetoric, you know the hepatitis B vaccine is almost as controversial as the HPV vaccine.)
Currently, in the United States, the Advisory Committee on Immunization Practices (ACIP) recommends that preteen girls and boys aged 11 or 12 are vaccinated against HPV. The immunization is also recommended for teenage girls and young women up to the age of 26 who did not receive it when they were younger, and teenage boys and young men up to the age of 21.
The “HPV vaccine caused neurological damage” retraction
The editors of Scientific Reports, an online, open-access journal published by The Nature Publishing Group, decided to retract a controversial paper that claimed to provide evidence that mice given the HPV vaccine showed symptoms of neurological damage. Setting aside the fact that animal studies are at the weaker end of the hierarchy of biomedical studies, a relatively low number of animal studies ever become clinically important to humans.
The fact that Scientific Reports published this article gave it some credibility. However, the quality of the research in the article was subject to withering criticism from scientists. According to a report in Science,
The paper was assailed by critics as being “pseudoscience” that could have “devastating” health consequences by undermining public confidence in a vaccine given to girls to prevent cervical cancer.
Despite the retraction, Scientific Reports stated that the “Authors do not agree with the retraction.” Since retractions can be devastating to academic careers, rarely do authors agree with retractions.
The research group that produced this study was located at Tokyo Medical University. As you may recall, the Japanese Ministry of Health, Labor, and Welfare, using controversial and scientifically unsound reasoning, withdrew its recommendation that the HPV vaccine be given to Japanese children. As a result, HPV vaccine uptake has dropped to nearly zero. This retracted study, which supposedly showed that the HPV vaccine caused neurological damage, probably did not help the discussion of HPV vaccine in Japan.
So what did the study show? Mice were given a huge dose of the HPV vaccine (beyond what we would give to humans) along with a toxin to make the blood-brain barrier “leaky” to the HPV vaccine. Of course, this is a good way to induce neurological changes, since generally, that barrier is impenetrable to anything that circulates in the blood, other than substances it actively transports into the brain. The toxin used by the researchers is simply not normal – it forcibly opened the blood-brain barrier to allow the extremely high dose of HPV vaccine to reach the brain.
Again, according to the Science article,
Shortly after the paper appeared, two groups separately wrote to Scientific Reports and its publisher, the Nature Publishing Group (NPG), pointing out problems with the experimental setup, the use of a dose proportionally far larger than what is normally given, the use of the toxin, and inconsistencies between the data presented and the descriptions of results, among other issues.
There was also concern about the strain of mice used, which make it less like that the experimental model could actually be applied to humans (overlooking the fact that the vast bulk of murine studies are ever applied to humans).
Lead author, Toshihiro Nakajima, vigorously defended the article after it was published. Another article, published in Science, reviewed an email from Nakajima and the critic’s comments, stating that, “critics are attacking the paper’s methodology and conclusions and are asking the journal to retract it in light of the potential negative impact it could have on public health.”
The retraction notice from Scientific Reports seems to side with the arguments presented by the critics of the Nakajima’s research. The retraction notice clearly states:
The Publisher is retracting this Article because the experimental approach does not support the objectives of the study. The study was designed to elucidate the maximum implication of human papillomavirus (HPV) vaccine (Gardasil) in the central nervous system. However, the co-administration of pertussis toxin with high-levels of HPV vaccine is not an appropriate approach to determine neurological damage from HPV vaccine alone.
The unfortunate result
This “HPV vaccine caused neurological damage” claim has become a standard trope of the anti-vaccine religion with regards to this cancer-preventing vaccine. Although there just isn’t any clinical evidence of a link between the HPV vaccine and any neurological issue, this poorly done mouse study always outweighs clinical data for the anti-vaxxers.
Why? Because the anti-vaccine mob uses the pseudoscience approach to logic – form a conclusion, that is, HPV vaccine is bad, and find only the evidence that supports that conclusion.
Real science, on the other hand, looks at all of the evidence, giving weight to higher quality and quantity evidence. Very recently, a high powered systematic review showed us that not only does the vaccine prevent cancer, it is also extremely safe. But we know that the anti-vaccine religion will ignore that study for any reason that hits their logic neurons.
Unfortunately, the editors at Scientific Reports took 18 months to retract this awful article. During that time, this paper was cited 20 times, mostly to be used as an argument that the HPV vaccine is defective in some way. The HPV vaccine is one of the very few ways to prevent cancer, and it was a travesty that the editors took that amount of time to retracts this pseudoscientific article
This article fed into Japanese fears about the vaccine, which contributed to the HPV vaccination rate dropping from around 70% in 2011 to nearly 0% today. Sadly, Japan has around 9000 cases of cervical cancer every year – and approximately 3000 deaths from HPV-related cervical cancer.
Of course, the anti-vaccine religion is whining, claiming some sort of mysterious conspiracy got this article retracted. They ignore the bad science presented in this retracted article, once again, because it supported their religious beliefs about vaccines.
At least the pseudoscience was retracted – but it’s possibly too little and too late for the teens and young adults of Japan, who could have been protected from insidious cancers.
The claim that the HPV vaccine caused neurological damage was based on a pseudoscientific article that should never have been published, except in a worthless predatory journal, like so many anti-vaccine “research.” Now, all we can do is push the affirmative evidence that the HPV vaccine prevents cancer and is extremely safe. And hopefully, the Japanese Ministry of Health, Labor and Welfare gets its collective intelligence back, and it begins to recommend the vaccine like most world health agencies.
- Aratani S, Fujita H, Kuroiwa Y, Usui C, Yokota S, Nakamura I, Nishioka K, Nakajima T. Retraction: Murine hypothalamic destruction with vascular cell apoptosis subsequent to combined administration of human papilloma virus vaccine and pertussis toxin. Sci Rep. 2018 May 11;8:46971. doi: 10.1038/srep46971. PubMed PMID: 29749388.
- Normile D. Critics assail paper claiming harm from cancer vaccine. Science. 2016 Dec 23;354(6319):1514-1515. doi: 10.1126/science.354.6319.1514. PubMed PMID: 28008018.