Monday, September 19, 2011

You're killin' me, Today

So this morning's Today Show featured Dr. Roshini Raj talking about “Four Vaccinations That Every Woman Should Get.” These turn out to be the flu shot, DTAP, HPV, and Hepatitis B.

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From the transcript:
Guthrie: The next one is the vaccine for Human Papillomavirus, better known as HPV. Now, I was under the impression that you, a woman only needs to get this when, you either get it when you’re young or it’s not worth getting at all.

Raj: Well, right now it’s FDA approved for age, for women aged 12 [sic] until 26. And we think that after the age of 26 that most sexually active women have probably been exposed to most strains of HPV, so it won’t be as effective. However, it still could probably protect some women over the age of 26. But certainly if you’re under 26, sexually active, you should be getting this vaccine. This is a truly remarkable vaccine that could help prevent most cases of cervical cancer, so it’s really important. And by the way, men under the age of 26 should also think about getting it. It protects against genital warts, and would protect against passing this virus to other women.
Doesn’t the Today show have fact checkers to verify these claims before they’re aired? Raj’s remarks give the impression that FDA approval for older women is likely, so they should seriously consider it. In fact, in April the FDA denied Merck’s request to extend approval for the vaccine to women 27-45. It is not approved for women over 26. Why on earth is a health expert presenting it as a vaccine “all women” should get?

Michele Bachmann’s comments have stirred up discussion of the vaccine again, but it’s almost as though few are bothering to learn about the most basic issues related to the vaccine or cervical cancer in the US. I’ve posted with some links on this thread at Pharyngula, but I recommend this New York Times article from 2008 and this other 2008 piece from Common Dreams. From the latter:
Merck would like to expand vaccination with Gardasil to much older women, but even if the FDA approved it, there are serious cost-benefit questions. Merck has suffered a regulatory setback of its owh this year, when the FDA rejected its application to legally extend the ages for which Gardasil can be marketed. Currently, it is approved for girls and women between the ages of 9 to 26. Merck wanted to extend that to age 45, and initial reports said Merck had data to support the extension that they would submit to the FDA by the end of this summer.

August, however, saw a flurry of news stories and medical journal articles that cast serious doubt on the efficacy and cost-effectiveness of vaccinating women later in life. The August 21, 2008 issue of the New England Journal of Medicine (NEJM) carried both an editorial and a lengthy study on HPV vaccines. The editorial was written by Dr. Charlotte J. Haug, editor of The Journal of the Norwegian Medical Association. She directly challenged the claim that HPV vaccination is effective at preventing cervical cancer. "Despite great expectations and promising results of clinical trials, we still lack sufficient evidence of an effective vaccine against cervical cancer," she wrote. "With so many essential questions still unanswered, there is good reason to be cautious."

The accompanying NEJM study, "Health and Economic Implications of HPV Vaccination in the United States," looks specifically at the cost-effectiveness of the HPV vaccine. Anytime someone raises the question of cost-effectiveness, of course, someone is bound to object that we can't put a price tag on human life. In reality, however, cost-benefit considerations always play a role in health decisions. With respect to cervical cancer in particular, the high cost of Gardasil compares poorly against simple Pap smears, which provide a time-tested, reliable and inexpensive diagnostic tool that can detect premalignant processes early and thereby prevent cervical cancer. It seems, therefore, that financial and public health sense should favor programs to ensure that all women, but especially those most at risk from cervical cancer, receive consistent and appropriate screening.

As for Gardasil, the NEJM study concluded that while the cost benefit of vaccinating twelve-year old girls falls within accepted guidelines for wealthy countries, the cost benefit declines rapidly as age increases. This finding is a major blow to Merck's efforts to promote intensive "catch up" vaccinations of girls and women who are over the age targeted by schools and proposed mandates. The benefit drops dramatically by the time women reach the maximum approved vaccination age of 26. In the even higher age range of 27 to 45 for which Merck is seeking additional approval, the calculated cost benefit is far outside the accepted range.

This information might seem to suggest that it is all the more important to vaccinate girls at the youngest age possible. Merck's Dr. Richard Haupt told the New York Times that the NEJM study "underscores the value of vaccinating pre-adolescent girls." But there is a big hitch. The NEJM study states clearly that its cost-benefit ratios are based on an assumption that the vaccine provides lifetime immunity to HPV. There is no evidence that this is actually the case. In fact, a number of indicators suggest one or more boosters will be needed during the recipients' lifetimes.

Even in the best-case scenario, HPV vaccines would only prevent 70% of cervical cancer cases, which means that regular and consistent screening, such as tried and true Pap smears, will remain critical for women's protection against cervical cancer. This means that the significant costs of the three shot initial Gardasil vaccination series (with a price tag of $450-$1,000, not including a possible booster) will be in addition to the existing costs of screening.

The NEJM article spelled out the bottom line: "If vaccine-induced immunity lasted only ten years, the vaccination of preadolescent girls provide only 2% marginal improvement in the reduction of the risk of cervical cancer as compared with screening alone."
It is irresponsible for those who are supposed to be educating the public about vaccines to make scientifically unsupported claims about them. It is also irresponsible to present HPV vaccines as a means of cancer prevention without noting declining effectiveness with age, the unknown duration of protection, the unknown long-term risks, and especially the fact that even the people who’ve received the vaccine prior to any exposure to HPV (and even if it turned out that the vaccine provided lifetime protection) still need to have regular Pap smears, as the vaccine only prevents the strains that cause 70% and not 100% of cervical cancers. There is a very real risk that people who’ve received the vaccine will believe themselves fully protected and forego regular cancer screenings. There’s also a risk that attention and resources will be diverted from screening, which is an extremely effective method of prevention (for all women and for all cervical cancers), educating about and reducing disparities in which could prevent the relatively few cases of cervical cancer that still occur in the US.

I have no medical expertise, so if anyone who does notices any errors in what I've prevented here I would appreciate the corrections.]

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