HPV vaccine's suspected side effects cause concern; CDC says drug is safe
12:00 AM CDT on Friday, June 6, 2008
Katherine Kimzey started suffering debilitating headaches, fainting spells and arthritis-like stiffness last November.
Six weeks later, the 14-year-old Dallas resident became so dizzy she could barely walk. She was hospitalized and missed three weeks of school.
Then, she had a seizure. For weeks, she bounced back and forth between specialists and was eventually diagnosed with epilepsy.
Katherine's mother, Michelle Kimzey, now believes her daughter's symptoms were caused by a new vaccine that was supposed to protect her against cervical cancer.
The symptoms started not long after Katherine had her second shot late last year, she said. And they mirrored many of the 5,000 reports filed by the public through a national database that monitors the safety of vaccines after they are licensed.
"When you read everybody's stories, they're too similar not to be related," Mrs. Kimzey said.
But officials with the Centers for Disease Control and Prevention and doctors nationwide said such concerns about the drug are unfounded and most significant side effects reported are unrelated to the vaccine.
"The safety of the vaccine is being very closely monitored," said John Iskander, acting director for immunization safety at the CDC, which runs the database along with the Food and Drug Administration.
Fainting, he said, has been the strongest negative response to the vaccine.
"There certainly have been high-profile suspected side effects, some reports of deaths," he said, "but those have been investigated and they don't appear to have been causally related."
The recommendations have not changed and the vaccine will remain available, he said.
Jennifer Allen, a spokeswoman for New Jersey-based Merck & Co.'s vaccine division, which makes Gardasil, said Thursday that the company conducted clinical trials for 10 years and that it remains confident in its product.
But this hasn't assuaged Mrs. Kimzey, 41. And Katherine has refused to get her third and final dose of the vaccine.
Gardasil was approved by the Food and Drug Administration two years ago for girls between ages 9 and 26. It protects against sexually transmitted diseases caused by the human papillomavirus, or HPV, responsible for 70 percent of cervical cancers and 90 percent of genital warts. Females are encouraged to get the vaccine before they become sexually active.
Three shots are given over a six-month period. The company said 16 million doses have been administered since its approval. And it lists nausea, vomiting and pain following the shot among the side effects.
The HPV vaccine has generated debate across the country and in Texas. Gov. Rick Perry issued an executive order in February 2007 requiring that all sixth-grade girls get the HPV shot. But angry parents and conservative groups fought the mandate, fearing it condoned premarital sex and took away parental rights. The Legislature defeated the order last April.
The National Vaccine Information Center heralded the decision, saying that testing of the vaccine was not extensive enough in girls under 12. The nonprofit center had already started warning about the possibility of adverse reactions such as extreme fatigue, arthritis and loss of consciousness.
Barbara Loe Fisher, co-founder and president of the center, said she's frustrated that the CDC has "assumed safety" for Gardasil, which has been tested only in conjunction with the vaccine for Hepatitis B.
Today, girls often receive the Gardasil shot at the same time as a meningitis vaccine and another new booster that immunizes against tetanus, diphtheria and pertussis.
The FDA has approved all the vaccines separately, but studies on administering them together are still ongoing.
"Not only was Gardasil put on the fast track and licensed quickly," said Ms. Fisher, "but to say safety is assumed and you can give any vaccine with it is even more shocking."
Joseph Bocchini, chairman of the Committee on Infectious Diseases for the American Academy of Pediatrics, says there's enough evidence to support mixing the drugs and not enough adverse reactions to stop it.
"From the data, we already know [the vaccines] would not be expected to interfere with each other in terms of antibody or safety," said Dr. Bocchini. "If we look at the number of doses given vs. the reports, it's very clear that there are significant benefits that far outweigh potential risks at this time."
Dr. Bocchini cautioned that reactions that do not occur immediately, like seizures, may actually be caused by something else. So far, he said, there have not been enough verifiable reports of extreme side effects through the Vaccine Adverse Event Reporting System, or VAERS, to generate a study.
Dallas County's Health and Human Services officials said they have received no reports of severe reactions to the vaccine.
The Texas Department of Health and Human Services said it had 210 reports of reactions to Gardasil last year, eight of which required hospitalization.
But officials said this is not an uncommon number for a vaccine. Dr. Jennifer Walsh said she will continue to encourage use of the vaccine where she works, the Adolescent Medical Clinic at Children's Medical Center Dallas.
"I'm still following the standard guidelines," Dr. Walsh said. "I don't have any worries at this point."