Addressing Questions About Gardasil
Recently, questions have been raised about the safety of Gardasil, a vaccine that prevents infection with types of human papillomavirus (HPV) that cause most cases of cervical cancer and genital warts, and some vulvar and vaginal cancers.
What is Gardasil?
Gardasil is a vaccine for use in girls and women 9 through 26 years of age. It is approved for preventing cancer of the cervix, vulva and vagina, and for preventing genital warts caused by the types of HPV contained in the vaccine.
These four HPV types (6, 11, 16, and 18) cause about 70% of cervical cancers and about 90% of genital warts. They are also known to cause some vulvar and vaginal cancers. (Percentages related to these conditions are not well defined.)
Why is Gardasil needed?
Gardasil may benefit the health of millions of people. Each year, more than 12,000 American women are diagnosed with cervical cancer, and almost 4,000 women die from this disease. In addition, about 6.2 million Americans become infected with genital HPV each year. Worldwide, cervical cancer is the second most common cancer in women, with 233,000 deaths per year.
Is Gardasil safe?
Based on ongoing assessments of vaccine safety information, the Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC) continue to find that Gardasil is a safe and effective vaccine.
Studies involving approximately 21,000 girls and women in the United States and worldwide were conducted to evaluate the safety and effectiveness of Gardasil before the vaccine was approved by FDA. Approximately half of the study participants received Gardasil, and the other half received a control.
Why have questions been raised about the vaccine's safety?
There have been reports of serious adverse events in girls and women that have received the vaccine. These include death and Guillain-Barre Syndrome (GBS), a rare neurological disorder that causes muscle weakness.
Should these reports worry me?
Based on the review and assessment of vaccine safety information available, FDA and CDC continue to find that the benefits of Gardasil outweigh the risks.
Twenty deaths had been reported to the FDA- and CDC-administered Vaccine Adverse Event Reporting System (VAERS) as of June 30, 2008, in women that received Gardasil.
However, no common pattern to these deaths has been detected that would suggest they were caused by the vaccine. In cases where autopsy, death certificate, and medical records were available, the cause of death was explained by factors other than the vaccine.
Given the large number of vaccine doses distributed, it is expected that, by chance alone, serious adverse events and some deaths will be reported in a large population during the time period following vaccinations.
The manufacturer, Merck and Co., has distributed more than 16 million doses of Gardasil nationwide. As of June 30, there were 9,749 VAERS reports of adverse events following Gardasil vaccination. Of these, 94% were classified as reports of non-serious events.
Also, FDA routinely reviews manufacturing information, and has not identified any issues affecting the safety, purity, and potency of Gardasil.