This week’s New England Journal of Medicine is a virtual smorgasbord of articles on HPV (human papilloma virus) vaccination. Although HPV also causes unsightly genital warts, HPV is more or less the sole cause of cervical cancer. I’ve written quite a bit here about Merck’s HPV vaccine, Gardasil, since a February 2007 executive order by Texas governor Rick Perry made the vaccine mandatory for sixth grade girls in the state but was subsequently overturned by the state legislature (and Perry announced just this Tuesday that he would not veto the bill, which had been passed by a veto-proof majority).
- An editorial in the NEJM summarizes the issue and the relevant articles.
- A clinical trial finds the HPV vaccine 100% effective at blocking disease caused by the four strains of HPV it protects against, and it finds the vaccine 20% and 34% effective at preventing all cervical and vulvar/vaginal lesions, respectively, caused by HPV in general.
- Another clinical trial found the vaccine 98% successful at blocking disease from these four strains and 17% effective overall at preventing the precursor to cervical cancer.
- An epidemiological study establishes a strong link between HPV infection and oropharyngeal (throat) cancer.
- A letter to the editor outlines the legal justification for mandatory HPV vaccination.
- Another article makes a more in-depth case for mandatory HPV vaccination.
- An editorial takes a more nuanced approach.
- A final article discusses HPV vaccination in developing countries.
In short, the vaccine is safe, and it is effective. It’s no surprise that it’s not 100% effective at preventing cervical cancer, given its limited scope. The fact that it prevents at least 17% of cases of cervical cancer should make its distribution a major public health priority. Given that its effectiveness decreases dramatically if there has been prior exposure to HPV, mandating it for sixth grade females is entirely justified. Also, given that HPV is so strongly linked to throat cancer, and given that males transmit HPV to females, vaccination in males as well should be a priority in the near future. All of this once again highlights the misguided nature of the Texas legislature’s decision to overturn mandatory HPV vaccination, and interested parties should continue to pressure the Texas legislature to reverse course.