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Dr. Amanda F. Dempsey

If you could have your child vaccinated against certain types of cancer, would you do it? Most parents would say "yes" without hesitation. Yet that response may not happen so readily when it comes to the new vaccine proven nearly 100 percent effective against some types of human papillomavirus (HPV), a common sexually transmitted disease. HPV is known to cause most cervical cancers, precancerous genital lesions and genital warts.



HPV and the New Vaccine

In June, the Food and Drug Administration OK'd Gardasil™, the first vaccine to target four troublesome HPV types. Approved for use in females ages 9-26, Gardasil was evaluated and approved in six months under the FDA's "priority review process," designed to fast-track products with the potential to provide significant health benefits. Gardasil is manufactured by Merck & Co., and GlaxoSmithKline is expected to follow soon with a similar product.

There are more than 100 types of HPV and about 30 that are transmitted sexually. Most HPV infections occur without any symptoms and go away without treatment. Yet, HPV infections sometimes persist for years and can cause detectable cell abnormalities. According to the National Cancer Institute, "Infection with certain types of HPV is the major cause of cervical cancer. … In 2006, an estimated 10,000 women in the United States will be diagnosed with this type of cancer and nearly 4,000 will die from it. Cervical cancer strikes nearly half a million women each year worldwide, claiming more than a quarter of a million lives." Some early studies suggest that HPVs may play a role in other cancers, as well.

That's why the institute has hailed the vaccine as a cancer-fighting breakthrough. "This vaccine opens a new era in cancer prevention," NCI Acting Director Dr. John E. Niederhuber said in a prepared statement. "It has the potential to save women's lives, as well as to reduce health disparities in the United States and around the world."

Gardasil is a recombinant vaccine (contains no live virus) that is given as three injections over a six-month period. It's not yet known whether booster vaccinations will be needed in the future. The key to the vaccine's effectiveness is that girls and women receive the shots before they are infected; the vaccine has no curative benefits for those already infected.

According to the FDA, the safety of the vaccine was evaluated in about 11,000 individuals. Most side effects were mild or moderate local reactions, such as pain or tenderness at the site of injection.



The Role of Parents

Since most females who would receive the HPV vaccine are underage, the role of parents is critical in battling potentially deadly HPV infections. That's what prompted a study by researchers at the University of Michigan C.S. Mott Children's Hospital. Researchers surveyed a random sample of 1,600 parents and primary caregivers with children ages eight to 12 to assess both their knowledge and attitudes regarding an HPV vaccine. Half the respondents randomly received a detailed information sheet explaining about the virus and the vaccine, while the other half did not.

Surprisingly, the fact sheet didn't seem to make much difference.

"What we found was that parents who received the information sheet did seem to improve their knowledge about HPV, but that improvement in knowledge didn't seem to translate into any type of increase in parental desire for HPV vaccination for their children," says Dr. Amanda F. Dempsey, the study's lead author. "Instead, what seemed to the most important factors in having parents want HPV vaccines for their children were underlying beliefs and their personal experiences."

Dempsey says parents who had experience with cervical cancer, precancerous genital lesions and genital warts — themselves, family members or friends — were more likely to want the HPV vaccine for their children. Parents who expressed concerns about the vaccine being uncomfortable or potentially unsafe were less likely to have their children vaccinated. "Some parents seemed to be against vaccination in general, and that translated into lack of support for the HPV vaccination," she says.

The vaccine has drawn fire from some conservative and religious organizations and individuals, claiming that vaccination might promote premarital and promiscuous sexual behavior in teens. While Dempsey's survey didn't address that question specifically, respondents still added their thoughts. "We had a few people, maybe 5 percent of the total survey population, who wrote in comments about their opposition to HPV vaccination because it wouldn't be necessary due to their religious beliefs and the upbringing of their children," she says. "On the other hand, we also had about a similar number of people talking at length about their support of the vaccine in the context of religiosity. There were comments all across the board." She adds that parents who bring religion and morality into the decision-making process are "a small minority," and that "cost, safety and vaccine efficacy" are much more common deterrents to vaccination.

Dempsey says another deterrent, though not addressed in the study, is the stigma of sexually transmitted diseases. "The HPV is so ubiquitous in our society that you really can't think of it in the same way as other sexually transmitted diseases," she says. "So many people who are not engaging in high-risk behavior are still getting infected, so I don't think it has the same connotation as some of the other sexually transmitted diseases." Thus, she says, medicine's goal should be to promote the vaccine as an expected and accepted healthcare measure for adolescent girls "without associating it with whether or not a girl is sexually active or about to become sexually active."

Armed with the findings of the University of Michigan study and others, Dempsey says it's time for medical providers "to get at the underlying beliefs behind parental consent for vaccinations. What our study showed is that just providing people with the facts about a given disease is not effective in changing some people's opinions. It's been shown in other literature, as well. The HIV research world is just filled with incidents of people understanding the potential implications of their high-risk sexual behaviors, but still continuing to do that."

Would Dempsey vaccinate a 12-year-old daughter of her own? "Yes, I would," she responds without hesitation. "There have been a number of studies looking at the average age of onset of sexual intercourse among teenagers, and something like 6 to 10 percent of children under the age of 13 are sexually active," she notes. "Nobody likes to think that it's their children."

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