Why we vaccinate – reduction in HPV incidence in UK

HPV incidence

The HPV quadrivalent vaccine, also known as Gardasil (or Silgard in Europe) prevents infection by the human papillomavirus, a sexually transmitted disease. The vaccine specifically targets subtypes 16 and 18, that cause not only approximately 70% of cervical cancers, but also they cause most HPV-induced anal (95% linked to HPV), vulvar (50% linked), vaginal (65% linked), oropharyngeal (60% linked) and penile (35% linked) cancers. It also targets HPV6 and HPV11, which account for approximately 90% of external genital warts. The viruses are generally passed through genital contact, almost always as a result of vaginal, oral and anal sex.

The HPV vaccine has been shown to be extraordinarily safe in two different and large epidemiological studies, one with over 700,000 doses and the other with over 350,000 doses. The absolute safety of the HPV vaccine is not in question except by those who engage in logical fallacies and anecdote.

In a recent study published in the journal Vaccine, researchers examined the HPV 16/18 infection rate in a randomized group of 4,178 young women, aged 16-24 years who were undergoing screening in community health services in the United Kingdom.

One of the key results was that in the group of 16-18 years, where the HPV infection rate dropped from 17.6% in a survey done prior to the introduction of the vaccine down to 6.6% post-vaccination. This group also showed the highest HPV immunization coverage, about 65%.

The authors concluded that:

[infobox icon=”quote-left”]These findings are the first indication that the national HPV immunisation programme is successfully preventing HPV 16/18 infection in sexually active young women in England. The reductions seen suggest, for the estimated coverage, high vaccine effectiveness and some herd-protection benefits.[/infobox]

These results mirror a study which established the substantial and dramatic drop in HPV infections after the release of the HPV vaccine in the United States. We can only conclude that the HPV vaccines caused a significant reduction in HPV incidence in UK and the USA. The HPV vaccine is effective.

The HPV vaccine is safe. The HPV vaccine prevents the HPV infection. And preventing HPV infections stop 60-95% of some serious and dangerous cancers and other annoyances such as penis pimples. Why is the decision to vaccinate with Gardasil even under discussion? Once again, here is scientific evidence that a vaccine saves lives.

Key citations:


One-dose HPV-vaccination still works to prevent cancer

The HPV vaccine prevents infection by human papillomavirus, a sexually transmitted disease, specifically subtypes 16 and 18, that not only cause approximately 70% of cervical cancers, but also they cause most HPV-induced anal (95% linked to HPV), vulvar (50% linked), vaginal (65% linked), oropharyngeal (60% linked) and penile (35% linked) cancers.

The viruses are generally passed through genital contact, almost always as a result of vaginal, oral and anal sex. There is strong clinical evidence that the incidence of HPV infections have declined since the launch of the HPV vaccine and the subsequent steady rate of HPV vaccination.

In a community-based phase III trial of Cervarix (bivalent HPV vaccine) in Costa Rica, researchers reported that the Costa Rica Vaccine Trial (CVT) showed that the four-year vaccine efficacy against 12-month HPV subtypes 16 and 18 (HPV16/18) persistent infections was similarly high among women who received one, two, or the recommended three doses of the bivalent HPV16/18 vaccine. The researchers examined nearly 7,500 women, aged 18-25, in Costa Rica to determine both vaccine uptake (what percentage were vaccinated), number of doses, and HPV16/18 antibodies.

Some of the key results:

  • About 80% of the participants did get all three recommended doses, leaving about 20% who got one or two doses.
  • Researchers analyzed blood samples for HPV16/18 antibodies in randomized subsets who received one, two or three doses.
  • Antibodies to HPV16/18 was observed in 100% of women 48 months after vaccination with one, two or three doses. The only difference noticed that it appeared to take a slightly longer average period of time for 100% of the one-dose group.
  • Almost all participants in all vaccine dose groups were seropositive at approximately 1 month after receiving the first vaccine dose and remained seropositive throughout the 48 months follow-up period.
  • The researchers also compared “a natural infection group” against those who were vaccinated with Cervarix. For those vaccine deniers who say “natural infection is better”, the titers of HPV16/18 antibodies were 14-24X higher with two-doses of the vaccine, while the titers were 5-9X higher with one-dose vaccinations.


The authors concluded:

The high efficacy after single dose suggests that long-term protection may not require the 5- fold higher titers induced by three doses of the vaccine. Fewer doses would be less expensive and logistically easier to deliver, therefore increasing vaccine accessibility worldwide. The findings also suggest that second generation vaccines might be strongly protective even if they do not induce the high levels of antibodies induced by the licensed vaccines as used according to current recommendations.

We know that the HPV vaccine is safe. Really safe in huge epidemiological studies. And we now have more evidence that it works, and it works better in protecting against HPV infections than so-called “natural immunity.” Unless you believe in lies from the antivaccinationists, HPV vaccines are one of the best ways to protect yourself from cancers.


If you need to search for accurate information and evidence about vaccines try the Science-based Vaccine Search Engine.


Key citations:

Anti-vaccine lunacy–more lies about Gardasil

One of the hallmarks of pseudoscience is an over-reliance on confirmation rather than refutation of a hypothesis. The antivaccine crowd are well-known for this particular violation of the scientific method. As discussed previously, science works on refutation–creating experiments that might actually disprove a hypothesis as a method to develop evidence in support of it. The anti-vaccination crowd actually hypothesizes (but not in a scientific sense) that a vaccine or set of vaccines was the causal factor in some side effect (autism, death, or whatever else), then they should establish an experiment (double-blinded of course) that would refute that hypothesis. If at some point, the data cannot refute it, then the anti-vaccinationists would have supporting data for their particular supposition. 

But instead of actually performing experiments (which cost money, which may show that they are wrong, or which might not be ethical), they resort to mining data to prove their point. Data mining is dangerous, because confirmation bias, that is, finding information or data that supports a belief while ignoring all other data that does not, makes the data suspect or even useless.

So, in that vein, the anti-vaccinationists often mine data from any database they can find, such as the Vaccine Adverse Event Reporting System (VAERS),  which is a program for vaccine safety, managed by the Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA). VAERS functions as a post-marketing safety surveillance program (similar to other programs for almost every regulated medical device and pharmaceutical) which collects information about adverse events (whether related or unrelated to the vaccine) that occur after administration of vaccines.

VAERS has numerous limitations, including lack of scientifically designed questions, unverified reports, underreporting, inconsistent data quality, and absence of an unvaccinated control group. VAERS is basically a collector of information, but has limited value in making conclusions since it does not provide information that is obtained in a controlled manner.  However, it does have some usefulness, in that certain trends may be spotted given enough time and data points. Continue reading “Anti-vaccine lunacy–more lies about Gardasil”

Smoking cannabis doesn’t cure cancer but it may cause it

Marijuana_Cures_CancerAs I have written before, there is a lot of controversy about medical uses for marijuana, although it appears to be much more of a political debate than a scientific one. There just isn’t much evidence that supports a hypothesis that marijuana has any significant therapeutic effect on diseases like cancer, neurological disorders, or other diseases.

Scientists have long suspected that smoking marijuana could be linked to lung cancer, but there has only been weak evidence supporting a causality.  Recently, a 40 year review of  over 49,000 men strongly suggests that smoking cannabis does indeed increase the risk of lung cancer. The study examined 49,321 men between the ages of 18 and 20 who were being enlisted in the Swedish military between 1969 and 1970, examining their health and lifestyle issues, along with their use of marijuana. The researchers reviewed other potential risk factors such as respiratory disease, other types of smoking, and socioeconomic status. Continue reading “Smoking cannabis doesn’t cure cancer but it may cause it”

Polio vaccine does not cause cancer–update

This article has been substantially updated with more information. Please check it out.

Vaccine myths are annoying, not just because they are dangerous to the public health, but because they are like the diseases prevented by vaccines, because the myths keep returning to infect the public, just when you’re not watching. It’s bad enough that social media sites (Facebook, Twitter, blogs, Google, reddit) continuously send out this pseudoscientific myths, but it’s the ersatz “news” sites that do the same. They retread old myths as if they are “breaking news”, which requires we skeptics and pro-science writers to jump out like a vaccine trained immune system to thoroughly destroy these antivaccine myths.

I have long ago accepted that there are just ignorant and plainly delusional people who will buy into any pseudoscience that shows up on their radar screen, without utilizing a single neuron for critical analysis. However, I also understand that there are people on the fence about vaccines (or any other issue with a pseudoscience counterargument), who will appreciate a thorough debunking of ignorant lies.

For example, I wrote an article a while ago about some nonsense meme on Facebook that contended that eating ripe bananas cured cancer because the bananas contained a protein called tumor necrosis factor (TNF). It was based on some “Japanese scientific study,” which took significant effort to find. After a critical and thorough reading of the article, I concluded that: the study made no claim that bananas made TNF, AND even if bananas did, you couldn’t ingest enough bananas to get a bioactive dose of TNF, AND even if you could, you wouldn’t absorb any TNF through the digestive tract, AND TNF doesn’t do what the meme writer thought it does (TNF is badly named, and does not directly attack cancers). In other words, the myth lacks any truth, except, maybe that bananas are yellow.

This is by far the most popular article I’ve ever written with probably close to 100,000 page hits. The reason is that every 2-3 weeks, the myth about bananas arises out of the background noise of the internet, people (unknown to me) use my article to debunk the banana myth in the comments section, and the myth slowly dies. But it never really completely dies. It’s only 99% dead. It’s a zombie which keeps coming back to life.

Thus, the best we skeptics can do is keep debunking these social media fables and tall tales, and move along to refuting the next one in line. At least I can save time by not having to write the article again, we can just update with any new information and re-debunk (yes, I have the absolute right to invent words). Continue reading “Polio vaccine does not cause cancer–update”

The importance of the HPV vaccine to gay men

cover-your-buttMany of us who provide scientific information about HPV quadrivalent vaccine, also known as Gardasil (or Silgard in Europe), tend to focus on its effects on preventing cancers in women, so articles are inclined to pay attention to vaccinating teenage girls rather than boys. But, if you carefully analyze the disease, human papillomavirus, a sexually transmitted disease, its subtypes 16 and 18 not only cause approximately 70% of cervical cancers, but they cause most HPV-induced anal (95% linked to HPV), vulvar (50% linked), vaginal (65% linked), oropharyngeal (60% linked) and penile (35% linked) cancers. The viruses are generally passed through genital contact, almost always as a result of vaginal, oral and anal sex. 

These HPV-related cancers can be prevented as long as you can prevent the HPV infection itself, either through never having genital contact with an infected person (and since about 79 million adult Americans are infected with the virus, that’s going to be difficult) or the HPV vaccine. The vaccine is a vitally important part of the war against HPV, it prevents the transmission of certain types (pdf) of human papillomavirus (HPV), specifically types 6, 11, 16 and 18. These subtypes of HPV are most often implicated in these cancers. Continue reading “The importance of the HPV vaccine to gay men”

Marijuana and cancer – Sanjay Gupta’s anecdotes are not science

Editor’s note–this article has been updated and included into a multi-part series on marijuana and medicine. Check it out there. 

Unless you were hiking in the Amazon River jungles, with no access to the internet or American TV, you probably have heard that CNN’s chief medical correspondent, Dr. Sanjay Gupta, changed his mind about marijuana (or “weed” as he keeps saying). Of course, this has become big news, because he’s such a “respected doctor” (why is that? Because he’s on TV?), and because a few years ago he was vociferously anti-cannabis.

I have no doubt that Dr. Gupta’s “conversion” to being pro-weed is genuine (and that his previous stance of anti-weed was similarly authentic), but we need to weed out what is real and what’s just smoke about his comments. His first major point about cannabis* was that the United States Drug Enforcement Agency (DEA) considers marijuana to be a Schedule 1 drug, which is defined as “drugs with no currently accepted medical use and a high potential for abuse.”

Dr. Gupta thinks this classification is ridiculous, and on the surface, many people, even those who are not devoted pot smokers, would probably agree. However, this is a political discussion, at least in the USA, and it is hardly a medical/scientific one. The chances of any political party having the fortitude to correct this classification is about as close to 0 as you can get, without actually stating that there is a 0 chance. But if Gupta wants to make a big deal of this, or that he’s so self-centered that he thinks he’ll change the mind of politicians, more power to him. But for me as a skeptic, it is not the most important thing he says.

In his article, he mentions a young girl who “started having seizures soon after birth. By age 3, she was having 300 a week, despite being on seven different medications. Medical marijuana has calmed her brain, limiting her seizures to 2 or 3 per month.” This is simply an anecdote of no quality whatsoever. Did he thoroughly investigate her case to determine if the number of seizures actually went down? Do we know that cannabis has anything to do with the change? Is this nothing more than a Post hoc ergo propter hoc fallacy, that just because she consumed cannabis and the seizures decreased does not mean anything about cannabis’ causative properties with regards to this type of seizure. And then, Dr. Gupta continues with the anecdotes by stating, “I have seen more patients like Charlotte first hand, spent time with them and come to the realization that it is irresponsible not to provide the best care we can as a medical community, care that could involve marijuana.” Why do these TV doctors (like Dr. Oz) think that their anecdotes are better than anyone else’s.

Anecdotes are useless because they aren’t controlled, because they are subject to all levels of bias, and because these stories aren’t peer-reviewed. In other words, anecdotes have no value in science-based medicine. Anecdotes do have value in formulating testable scientific hypotheses, but assuming that anecdote=data, and more anecdotes=more data is simply pseudoscientific. I don’t care what Sanjay Gupta writes or says publicly, but providing these stories as “evidence” that marijuana has a medical benefit is essential like telling me that he observed homeopathy (which is just water) working. It’s laughable.

Continue reading “Marijuana and cancer – Sanjay Gupta’s anecdotes are not science”

More evidence Vitamin D supplementation does not reduce breast cancer risk

vitamin-DPotential causes for cancer are numerous. InfectionsRadon gasCigarette smokingSun exposure. Obesity. With over 200 types of cancer, each with a different pathophysiology, there may be an equal (and probably greater) number of causes.

Although some cancers can be easily prevented, such as never smoking, which reduces your risk of lung cancer, one of the most prevalent cancers in the USA, by over 85%. Or getting the HPV vaccine (Gardasil or Silgard) which blocks HPV infections that are associated with several types of cancer, including cervical, anal, and penile cancers. Unfortunately, the sheer complexity and number of types of cancer means that there is probably not going to be any simple panacea to preventing (or even curing) cancer. In fact, some hereditary cancers, such as those individuals who carry genes that are implicated in breast and ovarian cancers, may not be preventable at all. 

Other than eliminating direct risks, are there things that can be done to actually prevent “cancer”? Once again, with over 200 types of cancer, this may be an impossibility, but the three most popular cancer prevention ideas are diet, vitamins and other types of nutritional supplements. Vitamins and other supplements are a $61 billion industry in the US. They generate these sales with minimal regulation, minimal quality control over the quality and dosage, and no requirement to actually provide evidence that the supplements do what is claimed by the supplement industry, aka Big Herbal. The FDA only gets involved with the industry if there’s some dangerous side effect, or when the claims of the industry are so outrageous that the FDA has no choice but to get involved.

Not too astonishingly, there just hasn’t been much evidence that cancer can prevented with supplements. Prostate cancer and fish oil? May actually increase risk, but generally no effect. Prostate cancer and soy? Nothing there either. Folic acid and cancer? May actually increase risk.  Continue reading “More evidence Vitamin D supplementation does not reduce breast cancer risk”

HPV vaccinations lagging despite strong safety and effectiveness

hpvThe CDC recently reported that only about half of US teenager girls have received the safe and effective quadrivalent HPV vaccine (HPV4), a disappointing level of vaccine uptake. Moreover, this rate hasn’t changed over the past three years, despite significant efforts to increase the awareness and effectiveness of the vaccine amongst teenagers. Even worse news in this report is that only about one-third of teenage girls have been fully immunized with all three doses.

HPV quadrivalent vaccine, also known as Gardasil (or Silgard in Europe), is marketed by Merck & Co., usually for vaccination of teenage girls (with an increasing number of boys). The vaccine prevents the transmission of certain types (pdf) of human papillomavirus (HPV), specifically types 6, 11, 16 and 18. 

HPV types 16 and 18 cause approximately 70% of cervical cancers, and caused most HPV-induced anal (95% linked to HPV), vulvar (50% linked), vaginal (65% linked), oropharyngeal (60% linked) and penile (35% linked) cancers. These cancers, mostly related to HPV, can be prevented as long as you can prevent the HPV infection from ever happening, which usually happens through genital contact, most often during vaginal and anal sex.

HPV may also be passed on during oral sex and genital-to-genital contact. HPV can be passed on between straight and same-sex partners—even when the infected partner has no signs or symptoms. Approximately 79 million Americans, most in their late teens and early 20′s, are infected with HPV, and about 14 million people become infected each year in the USA. Continue reading “HPV vaccinations lagging despite strong safety and effectiveness”

Soy supplements and prostate cancer–no effect

Tofu is displayed in a supermarket in Santa MonicaOver the past few years, some research has suggested that there might be a correlation between high soy consumption and lowered prostate cancer risk. Most of the research suggesting the link was observational or based on animal studies on the role of soy supplements on the risk of prostate cancer, or on the risk of recurrence of the cancer after treatment.

According to the American Cancer Society, there is some logic to a potential causal relationship between soy consumption and risk of prostate cancer:

Plant estrogens (phytoestrogens) were first identified in the early 1930s. At that time it was discovered that soybeans, willows, dates, and pomegranates contained compounds that were much like estrogens. Scientists began studying the role isoflavones play in reducing breast cancer risk in the 1960s. In a 1981 prospective study in Japan, researchers found that daily intake of miso, a soybean paste, was linked to lower death rates from stomach cancer in more than 260,000 men and women. Around that time, other studies on soy began to be published in the United States. In October 1999, the U.S. Food and Drug Administration (FDA) agreed to allow health claims about soy’s role in reducing heart disease on food products containing soy protein. Continue reading “Soy supplements and prostate cancer–no effect”