December 7, 2010
I am pleased to have the opportunity to testify on behalf of the National Research Center for Women & Families, and our Cancer Prevention and Treatment Fund. I have a Master’s in Public Health and am here today to comment on Gardasil.
Our Center is dedicated to improving the health and safety of adults and children, and we do that by scrutinizing medical and scientific research to determine what is known and not known about specific treatments and prevention strategies. We do not accept contributions from companies that make medical products.
Guillain-Barré syndrome is one of the “conditions of special interest” being closely monitored among individuals vaccinated with Gardasil. In the general population, GBS has an average weekly incidence of 0.65-2.57 cases per week per ten million people. As those numbers indicate, this sometimes fatal condition causing temporary and even permanent paralysis is, thankfully, exceedingly rare. It is, however, one of the known neurological sequelae of vaccination. The question is: Is GBS more prevalent among people receiving Gardasil?
In a new study to be published in Vaccine, Nizar Souayah and co-authors looked at the VAERS database between June 2006 and September 2009 and compared the occurrence of Guillain-Barré syndrome after vaccination with Gardasil to the occurrence after vaccination with Menactra and influenza. The researchers concluded that the average weekly reporting rate of GBS for the six weeks after vaccination was 6.6 events per week per 10 million subjects, which is double what it was for Menactra (also administered to children 11 and up), and about five times the weekly reporting rate for flu vaccine. When limited to the first two weeks after vaccination, the average weekly reporting rate of GBS jumped to 14.5 cases per week per 10 million subjects vaccinated with Gardasil as compared to 5.7 cases among subjects vaccinated with Menactra.
Three CDC researchers appropriately point out that the VAERS database has numerous shortcomings and that the authors used as their denominator the number of doses distributed, divided by 3, even though not everyone receives all three doses. They also maintain that being a new vaccine, adverse reactions to Gardasil were over-reported. We disagree. While the authors may have worked with too small a denominator, we believe they also worked with too small a numerator. Because VAERS is a passive system that depends on voluntary reporting, adverse reactions are always under-reported. Most parents don’t know how to report problems or don’t find the time to do so, and many doctors under-report as well.
Should we be concerned about the safety of Gardasil?
All of us are here today because we care about the safety of pediatric medications and vaccines. Moreover, as public health professionals we all recognize that a certain amount of individual risk is acceptable for the public good. This is why we can’t talk about Gardasil’s safety without discussing its efficacy. We must ask what level of protection does it offer and for how long? We must weigh the vaccine’s risks and costs against its benefits, knowing that the balance sheet will look different in each country and even in different communities.
Gardasil’s use continues to expand in the U.S, even though cervical cancer screening is affordable and widely available, and penile cancer and vulvar cancer, for instance, are extremely rare. Here in the U.S., Gardarsil’s main benefit is a reduction in abnormal PAP tests and excisional therapies for CIN2 and 3 lesions. Will Gardasil prevent cervical cancer? We still don’t have the long-term data to determine that. Similarly, we don’t know how long this vaccine-one of the most expensive vaccines and the most expensive routine vaccination ever-lasts. Without that information, vaccinated girls and women, as well as boys and men, could become complacent and fail to take proper precautions.
The modeling analysis done by Ruanne Barnabas shows that a cervical cancer vaccine must last at least 15 years in order to prevent cancer and not just postpone it. According to the data we have on Gardasil so far, its protection is expected to last at least five years. While no one understands or can agree on the level of antibody titers necessary to have protection from HPV, there are data indicating that a significant percentage of vaccinated girls lose their antibody response within five years. Are they still protected? What about 8 years after being vaccinated? What about 10 years after? If we find out that booster shots are needed, will young adults who were vaccinated as children actually get them? What if the booster is expensive and they don’t have coverage for it?
Unless the long-term data prove that Gardasil’s protection lasts significantly longer than five years, we may find that girls and boys vaccinated as pre-teens are losing their immunity when they are most sexually active.
Although Gardasil is safe for most people, Souayah’s study found that girls and young women vaccinated with Gardasil were 8.5 times more likely to visit the ER, 12.5 times more likely to be hospitalized, 10 times more likely to have a life-threatening event, and 26.5 times more likely to have a disability than young people vaccinated with Menactra.
Those numbers would be acceptable if Gardasil saves lives, but we don’t yet know if it will.
In summary, the FDA approved Gardasil on the basis of short-term research, and we don’t yet know how long Gardasil provides protection or when a booster shot will be needed. We also don’t know whether vaccinated girls will grow up to be women who are less likely to undergo PAP smears or HPV testing because they think they are guaranteed to be “one less” woman with cervical cancer, as the ad campaigns have promised. There are a lot of unanswered questions, and we hope you will recommend that the FDA regularly re-evaluate Gardasil’s use as new research data on safety and efficacy become available.