There's been a lot of controversy about the HPV vaccine since is was approved by the FDA in 2006. Parents, public health officials and politicians have been arguing about whether the vaccine might promote sexual activity in teenagers, is safe, or is just too expensive. Now an essay published online in the Annals of Medicine suggests that the vaccine has been promoted based on inaccurate information. If you're thinking about getting the vaccine for yourself or for your children, read on.
- The HPV vaccine may not work. The clinical trials showed no evidence that HPV vaccination can protect against cervical cancer. It turns out that the efficacy of the vaccine (Gardasil, by Merck & Co and Cervarix by GlaxoSmithKline) has not been proven; the study period was too short. Although invasive cervical cancer can take 20 to 40 years to develop from the time of HPV infection, the follow-up in the phase 2 trials for Gardasil was only five years, and for Cervarix it was just 8.4 years. No one knows how long the vaccine will last. If the vaccine is given to 11-12 year olds, but lasts for only 10 years, then women who are in the early 20's would no longer be protected.
- The HPV vaccine may not lower the rate of cervical cancer. With the level of Pap smear screening now done in the U.S., 8 out of 100,000 women get cervical cancer. Cervical cancer is rare in the U.S. Contrary to claims that cervical cancer is the second most common cancer in women worldwide, existing data show that this only applies to developing countries. With the vaccine -- assuming that it lasts a lifetime -- and without Pap smear screening, it's predicted that 9.5 out of 100,000 women will develop cervical cancer. In other words, the impact of the vaccine would be quite small.
- The risks of the vaccine may exceed the benefits. The World Health Organization says there are about 1.7 deaths from cervical cancer out of 100,000 women. But that is 2.5 times lower than the rate of serious adverse reactions from Gardasil. Reported adverse reactions include death, paralysis, facial palsy, chronic fatigue syndrome, automimmune disorders, pancreatitis and pullmonary embolism, among others. Since the vaccine was approved in the U.S., there have been almost 19,000 adverse reactions reported to Vaccine Adverse Event Reporting System (VAERS), of which 8% were serious, and there have been 68 deaths.
What's needed is independent evaluation of HPV vaccine safety and long-term data to evaluate how long the vaccines really last. The researches say pediatricians and other physicians need to be less enthusiastic about the vaccines when discussing their availability with parents and young adults, and base their recommendations on the actual evidence.
So much in health care depends on which risks you're more inclined to take. At this point, the push to get kids the HPV vaccine may be way ahead of the data we need.


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