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July 8, 2008 -- The vaccine Gardasil is making headlines -- but this time, it's about reported side effects and safety concerns.
The CDC and FDA have gotten 7,802 reports of adverse events in people who were vaccinated with Gardasil, the first cervical cancer vaccine, between June 8, 2006, and April 30, 2008. And two lawsuits have been filed, according to media reports, over Gardasil's safety.
Gardasil hasn't been proven responsible for any reported adverse events.
Is Gardasil safe? And what should parents do if they're concerned about letting their daughter get vaccinated with Gardasil?
WebMD contacted the CDC, Merck (the drug company that makes Gardasil), and an independent expert who's closely following Gardasil for their answers. But first, here's a quick recap of Gardasil's history.
(Have you considered giving your daughters the HPV vaccine? We're discussing it on WebMD's Parenting: Preteens and Teenagers board.)
In June 2006, Gardasil hit the market as the first cervical cancer vaccine. Gardasil targets four strains of human papillomavirus (HPV) linked to many, but not all, cervical cancers and to genital warts.
Safety data reviewed by the FDA in approving Gardasil was based on about 11,000 people. Most side effects were mild or moderate reactions, such as pain or tenderness at the injection site.
In January 2007, the CDC added Gardasil to its routine childhood immunization schedule. The CDC recommended Gardasil, given in three doses, for all girls aged 11-12 and even for girls as young as 9, with catch-up doses for girls and women aged 13-26 who hadn't been vaccinated earlier.
More than 26 million doses of Gardasil have been distributed worldwide, including nearly 16 million in the U.S., according to Merck, which estimates that at least 8 million females in the U.S. have received their first dose of Gardasil.
The CDC and FDA monitor adverse events reported in people who get any vaccine, including Gardasil. All those reports go into the Vaccine Adverse Events Reporting System (VAERS).
The 7,802 adverse events reported to VAERS for Gardasil include 15 deaths and 31 reports of Guillain-Barre syndrome, a potentially paralyzing, life-threatening condition in which the body's immune system attacks part of the nervous system.
But the VAERS data doesn't tell the whole story, notes John Iskander, MD, MPH, the CDC's acting director of immunization safety.
"VAERS receives unconfirmed reports of possible side effects" that may require further study, Iskander tells WebMD. That is, the reports don't show whether Gardasil caused the reported problems. Publicity tends to increase VAERS reports, and Gardasil has gotten a lot of publicity, says Iskander.
The serious reported events are about half of what's average for vaccines overall, according to the CDC.
The CDC hasn't been able to establish Gardasil's role in 10 of the deaths reported to VAERS; patient information wasn't available for the other five reported deaths.