The human papillomavirus has the dubious distinction of being the sexually transmitted disease you are most likely to get. It’s also the leading cause of cervical cancer. January has, somewhat arbitrarily, been dubbed Cervical Health Awareness Month (also National Hobby Month and Hot Tea Month, the last at least for good reason). While cervical cancer is the disease most commonly associated with HPV, a recent report from the American Cancer Society emphasizes that HPV’s threat is not gender-specific or organ-specific. While cervical cancer cases are in decline (as are general cancer rates), cancers linked to HPV are on the rise.
The increasing prevalence of HPV-linked cancers should permanently alter our limited conception of the disease as chiefly a women’s issue. Oropharyngeal (which I’ll be vulgarizing as “oral”) and anal HPV-related cancers (which particularly afflict men who have sex with men) are becoming more common. Oral malignancies account for 37.3 percent of HPV-related cancers, edging out cervical cancer, which makes up 32.7 percent. For men, oral cancers make up 78.2 percent of total HPV-related cancer incidences, and they account for 11.6 percent of cases among women. The death rate for oral cancer is three times higher than that for cervical cancer. (About 40 percent of penile cancer cases are HPV-related, but rates of the disease have basically remained static.)
Historically, most oral cancer cases were caused by smoking and heavy drinking and tended to manifest later in life. But even though fewer Americans indulge in these vices today, more of them are engaging in oral sex. Oral cancer rates have risen and begun showing up in younger individuals who, sensibly, seem to prefer oral sex to cigarettes. As the Oral Cancer Foundation notes, HPV strain 16 “is conclusively implicated in the increasing incidence of young non-smoking oral cancer patients.” If the disease is detected, the survival rate for HPV-related oral cancer is higher than for the alcohol- and tobacco-correlated versions. But HPV-related cases are often harder to catch because the disease occurs deeper in the mouth (the base of the tongue is a common location), and the warning signs are not as obvious.
There are, of course, HPV vaccines, which the CDC describes as “very effective” and “very safe.” Merck released another study in October that found that Gardasil, the company’s vaccine, may cause fainting and brief skin irritation but “no link with more serious health problems was found.” The Gardasil vaccine defends against four HPV strains: 6 and 11, which cause 90 percent of genital warts; and 18 and 16, which are linked to cancer. It is FDA-approved and CDC-recommended for males and females. Cervarix defends against the same two cancer-causing strains and a few other lesser culprits. It is not licensed for men. Most insurance companies and public health programs will cover the cost of the HPV shots for those who fall between the FDA-licensed ages of 9 through 26 years old.
But while both vaccines successfully defend against various strains of HPV, only Gardasil has been specifically tested and proven to protect against vulvar, vaginal, and anal cancers as well as cervical cancer. The vaccines’ preventive abilities have not been proven for other cancers, which prevents the companies from advertising the vaccines’ usefulness against the most prevalent danger: HPV-related oral disease. As the CDC notes: “It is likely that this vaccine also protects men from other HPV-related cancers, like cancers of the penis and oropharynx (back of throat, including base of tongue and tonsils), but there are no vaccine studies that have evaluated these outcomes.” Last year the National Cancer Institute declined to fund proposed clinical trials on the efficacy of the vaccines for oral cancer, possibly due to budgetary constraints. (NCI officials were not able to respond before publication.)
“The very low rate at which boys are vaccinated is a result of the inability of the manufacturers and doctors to speak openly and with factual evidence about oral cancer in a context that parents will understand,” says Brian Hill, president of the Oral Cancer Foundation, who was present at the National Institute of Health meeting where the aid was requested. He says more data and publicity for the vaccines could improve the vaccination rate in boys, which in 2010 was only 1.4 percent. “Vaccination is not just about cervical cancers but cancers their sons will potentially get in the future.”
The dangers of HPV may sound pretty disturbing, particularly for those who might have shrugged off the virus’s threat because they believed it wouldn’t imperil them or their children. But there are a few important things to understand about HPV. First, we aren’t all doomed. A lot of scary statistics get batted around about HPV—6 million new infections a year! Half of sexually active people will get it in their lives!—but most of the 130-plus strains appear to do no damage, and most people’s immune systems recognize the handful of dangerous strains as something nasty that should be destroyed.
But an unlucky 1 percent of the population will not produce the antibodies necessary to defeat the invaders. And it is basically impossible to know whether you or one of your partners is part of that 1 percent. There isn’t a reliable blood test to tell whether your body is making antibodies against the virus and is thus protected naturally and you don’t need the vaccine.
The vaccines work best in those who have never had sex and therefore have never been exposed to any strain of the virus. That means the safety and efficacy of the vaccines are of limited comfort to those who were sexually active prior to 2006, when the vaccine first became available to females (in 2009 males were officially given the OK).
After a certain age, 26 in the United States, it is assumed most people have had enough sexual partners that they have been exposed to HPV and their bodies have produced the antibodies necessary to defeat it on their own. In the case of women who have been exposed and developed an infection, it is thought that cervical abnormalities will have been detected and dealt with. Vaccinating people after a long sexual history simply isn’t worth the cost, from a public health perspective.