Politics of the new HPV Vaccine

There is a new article in the NEJM this week about the implications of mandated HPV vaccination in the US. Texas and Virginia have mandated that girls at roughly 5th grade age be vaccinated. The Texas executive mandate has been widely talked about in the news, and this article in the New York Times illustrates some of the political battle that has occurred. Meanwhile, several states have rejected this kind of legislation, while a dozen others are currently exploring some sort of response to the new vaccine, Gardasil, recently released by Merck.

First, a little information on HPV. a great review article is "Vaccines for the Prevention of Human Papillomavirus and Associated Gynecologic Diseases: A Review" by Dr. Kevin Ault. How important is HPV in developing cervical cancer? There are several aspects to this group of viruses that can cause warts. There are over 100 of these viruses, not all of which can cause cancer. The wart that people get is a local manifestation of HPV; the skin that sheds off of that contains the virus.

HPV is a double stranded DNA virus with an icosahedral capsule around the DNA and a membrane, or envelope, around this. Some of its gene products affect the machinery of the cell, such as by inhibiting p53, a protein that regulates the cell to make sure it isn't defected when it replicates.

HPV 16 and 18 are the two most implicated in cervical cancer -- they appear to be involved in about 70% of these cancers. Interestingly, some strain of HPV is found in more than 99% of cervical cancers. It makes sense that vaccinating against something that is so closely linked epidemiologically could slow down or eliminate much of the disease.

Part of the controversy is that HPV is considered a sexually transmitted disease. Two of the other strains covered by the vaccine are HPV 6 and 11, which together cause roughly 90% of genital warts. These are unsightly, but tend to not be much of a health problem. Nonetheless, the political debate rages over whether treating this so-called std is in effect advocating for promiscuity and lax morals.

The vaccine works incredibly well, being practically 100% effective in creating antibodies against these 4 types of HPV. It brings us to the interesting ethical impasse that so many state legislatures also find themselves at: in one hand a quasi-miracle vaccine and in the other the weight of their constituency's moral demands.

One point is that HPV aims to protect the single vaccinated person, instead of the herd. This is different from other vaccines, which get spread from person to person and thereby can cause herd immunity with less effort. Also, HPV is an expensive vaccine, and the mandate is for girls between ages 11 and 12, rather young.

Some argue that introducing this at an early age suggests a mandate for sexual promiscuity. However, that has not happened with education about AIDS or pregnancy, which are more imminent dangers than cervical cancer. As the NEJM points out, it is almost as if recognizing that teenage sexual activity occurs is the same as endorsing such activity.

Compounding the concern is the fact that girls who begin sexual activity early may be those at highest risk for obtaining HPV, and of a lower socioeconomic status. As it is available today, the vaccine costs $119.75 per dose, in a series of three doses. Clearly, without a change in policy, these most at-risk populations would be among the last to benefit from the commercially available vaccine.

The issue remains controversial politically, but scientifically, it is clear that this vaccine can provide an almost instant public health benefit. The Centers for Disease Control (CDC) has voted unanimously that girls of 11-12 years receive the vaccine, and added Gardasil to the Vaccines for Children Program, which gives free vaccines to needy children.