In the past several weeks, concerns have been raised about the safety of the cervical cancer vaccine (Gardasil). There have been 10 reported cases of a paralyzing neurological condition called Guillain-Barre Syndrome (GBS). Lost in the commotion is the fact that GBS occurs in the teen population even without vaccination – and the predicted number of cases among the 8 million girls and young women who have received Gardasil would have been 40 cases WITHOUT getting the vaccine That means, there are actually fewer cases of GBS in those receiving the vaccine than would have been expected WITHOUT the vaccine!
Here’s a little background about cervical cancer and the Gardasil vaccine:
Gardasil protects against infection with certain strains of human papillomaviruses. The human papillomaviruses cause warts, those on the hands and feet, as well as sexually-transmitted genital warts (see Chapter 3, Germ Proof Your Kids – The Complete Guide to Protecting (without Overprotecting) Your Family from Infections [ASM Press, Washington, D.C., 2008]). Importantly, papillomaviruses also cause most cases of cervical dysplasia and cervical cancer. Papillomavirus infections are the most common sexually-transmitted disease in the U.S.; as many as two-thirds of adolescent girls are infected in some communities studied, and most new infections each year occur in adolescents and young adults. The same papillomaviruses also cause genital cancers in men and some cases of cancers in the mouth. According to the American Cancer Society, as many as 10,000 new cases of cervical cancer are diagnosed each year, virtually all due to the strains of papillomaviruses included in the vaccine. The current vaccine produces high levels of protective antibodies in nearly 100% of women studied. In prevention trials of the vaccine in 16-26 year old girls and women, the vaccine was found to be 95-100% effective in preventing genital warts, cervical dysplasia, and early cancer changes in the cervix. The protection was only against those strains of the virus with which the women had not yet been infected; there was no effect of the vaccine on already existent papillomavirus infections. The vaccine must be given to girls and women before they have the chance to become infected – but even if already infected with one or more of the four high risk strains, immunization was found to be protective against the remaining strains included in the vaccine preparation. Immunity appears to persist for at least 5 years after the vaccine, and at present no booster shots are recommended. Studies are continuing in men – the vaccine produces high levels of protective antibodies in men as well, but it is not yet known if there will be an effect on reducing actual infections as has been shown for women.
Safety: As with most vaccines, local reactions (pain, redness, swelling) at the site of injection are the most common side effects; 95% of all bad reactions reported so far with Gardasil have been of this minor variety. Fever developed in 10% of those vaccinated, but also in 9% of those getting a placebo (see Chapter 12, Germ Proof Your Kids – The Complete Guide to Protecting (without Overprotecting) Your Family from Infections ). Among the 16 million doses of Gardasil given to approximately 8 million girls and young women to date, only 7 percent have been classified as “serious” – this compares with a 10-15% “serious” reaction rate reported for other vaccines which are also considered to be very safe.
While the Gardasil vaccine should continue to be regarded as a very safe vaccine, certain cautionary notes are worth mentioning. Although the vaccine protects against the most common papillomaviruses that cause genital warts and cervical cancer, it does not protect against all papillomaviruses or all causes of abnormal cervical changes in women. Pap smears and cervical screening examinations will still be required for those immunized.
Many states are now considering mandating immunization against papillomaviruses for all girls entering middle school. It is up to individual states to determine required immunizations for school and day care entry (see Chapter 7, Germ Proof Your Kids – The Complete Guide to Protecting (without Overprotecting) Your Family from Infections ). Because papillomavirus infections are sexually-transmitted, only sexually active adolescents are at risk. This has caused objections to mandated immunization against papillomaviruses by some parents and religious organizations that prefer abstinence as a preventive against sexually-transmitted diseases. And, indeed, abstinence is preventive against acquisition of this infection. However, studies show that 65-70% of adolescent girls and boys are sexually active by the end of high school and that more than 10% of 11th graders have already had four or more sexual partners. By the timie a woman is 50, there is an 80% chance she will have been infected with papillomaviruses. The vaccine is only effective if given before sexual exposure to the strains in the vaccine occurs (see above). Traditionally, mandated vaccines have been those that prevent infections that readily spread within the school community. The sexual pattern of spread of papillomavirus infections has generated debate regarding whether it satisfies the usual criteria for mandated vaccines. Tetanus immunization also does not satisfy the traditional criterion of classroom contagiousness, but it is included in the diphtheria and pertussis vaccine preparations that do protect against school contagions.
Along similar lines, some parents and religious organizations have expressed concern that immunization against a sexually-transmitted disease sends the message to kids that sexual activity is expected and even permissible (see Chapter 7, Germ Proof Your Kids – The Complete Guide to Protecting (without Overprotecting) Your Family from Infections). Additionally, some have worried that immunized girls might be less cautious sexually because they feel “immune”, and therefore potentially put themselves at risk for other sexually-transmitted diseases and pregnancy.
The current vaccine is very expensive – almost $400 for the 3 doses, in addition to clinic visit charges. Some, but not all, health insurance plans cover the vaccine and clinic visits, but many adolescents in the highest risk communities are uninsured.
This is a good vaccine and it should be given to adolescent girls to protect them from the potentially devastating effects of papillovirus infections, namely cervical cancer. Headlines are typically misleading. For a guide on how to react, and not over-react, to the news of each day, see Chapter 12 in Germ Proof Your Kids – The Complete Guide to Protecting (without Overprotecting) Your Family from Infections.