Even as Gardasil enters more extensive use, controversy persists over the safety of the vaccine, which protects against human papillomavirus (HPV). The Food and Drug Administration (FDA) approved the vaccine for use in the United States in 2006, but the question of whether it's safe to have a preteen or teenage daughter or son immunized remains a core issue.
The Centers for Disease Control and Prevention (CDC) recommends vaccinating girls and young women ages 9 to 26, and last October, the FDA approved Gardasil to protect against HPV for males in the same age group. More than 23 million doses of the vaccine have been distributed as of 2008.
Gardasil is the only vaccine approved to protect against four types of the 100 or so strands of HPV. It is widely regarded as an effective intervention because it is affordable and has the potential to stem a large number of incidents of HPV and cervical cancer that often go undetected and untreated.
HPV is spread by direct contact and causes warts, including in the genital area. Some types also can cause changes in a woman's cervix that lead to cervical cancer. HPV is often undetectable and women may not have any symptoms of infection. They may only discover they have contracted the disease through an abnormal Pap test result.
Even when they are immunized with Gardasil, regular screenings for cervical cancer through Pap tests are recommended, since the vaccine does not fully protect all women from getting cervical cancer.
The arguments for administering Gardasil are compelling. It protects against a virus responsible for 70 percent of incidents of cervical cancer, an illness that continues to kill approximately 4,000 women annually in the United States.
Dr. Kevin Ault, associate professor of gynecology and obstetrics at Emory University in Atlanta, says the statistics favor Gardasil. "There are 772 serious problems identified in 23 million doses of vaccine," he said in an August article on ABC News online. "I usually tell my patients that these serious events are tragic, rare and likely unrelated to the vaccine."
Because the vaccine is relatively new, however, questions are still emerging as to its safety and the risks versus benefits of immunization for all teenagers. A government report released in August 2009 raised the latest set of high-profile safety questions. It found that Gardasil was linked to 32 unconfirmed deaths since its release as well as higher incidences of fainting and blood clots than other vaccines. Sheila and David Rothman wrote an editorial in the Journal of the American Medical Association that accompanied the report. It suggested the educational material physicians received about Gardasil did not address "the full complexity of the issues surrounding the vaccine and did not provide balanced recommendations on risks and benefits."
"Although the number of serious adverse events is small and rare, they are real and cannot be overlooked or dismissed without disclosing the possibility to all other possible vaccine recipients," Dr. Diane Harper, director of the Gynecologic Cancer Prevention Research Group at the University of Missouri, told ABC News online in response to the report.
Other research also raises red flags. Findings presented at the annual meeting of the American Academy of Neurology in May 2009 by researchers from the University of Medicine and Dentistry of New Jersey indicated that within two to six weeks after receiving an injection of Gardasil, females have heightened vulnerability to Guillain-Barre syndrome, a potentially deadly condition in which the body's immune system attacks its nervous system. They found that women who receive Gardasil are up to six times more likely to contract Guillain-Barre within six weeks of the treatment than people in the general population. The total number of those at risk are low, but it's still unknown why Gardasil triggers this serious disease.
Once thought of as a lifesaver for low-income and minority women, who average much higher rates of cervical cancer because of undetected HPV, the vaccine has been losing some of its initial luster as risks related to its usage surface.
Merck, the manufacturer of Gardasil, maintains that its vaccine is extremely safe. Other proponents of the vaccine agree, saying it is well-tolerated. They report that the most common side effects in both men and women are pain or swelling at the injection site, headache, fever, nausea, dizziness, vomiting and fainting.
Reports of adverse events — health problems that occur after getting a vaccine, which may or may not be related to the medication — for Gardasil, however, are about five times as high as the overall average for any other vaccine, according to John Iskander, associate director for immunization safety at the CDC. In 2009, Gardasil was linked to severe allergic reactions in at least five confirmed cases of young women in Spain and Australia.
Since the vaccine is new, reports on its safety are still emerging. Without enough evidence, though, it can be difficult for concerned parents to make an informed decision. One thing is clear: More research, study and discussion are needed. For more information, visit www.cdc.gov/vaccinesafety/Vaccines/HPV/hpv_faqs.html.
Sharon Ufberg is a senior clinician and adjunct professor at Beth Israel Medical Center's Continuum Center for Health and Healing in New York City. She holds a doctorate in chiropractic.