Vaccine controversies continue to make news, with several stories making headlines within the past week. Several news outlets recently reported (e.g., here and here) on a study published in The Lancet that challenged conventional wisdom about the effectiveness of flu vaccines. According to one report, until recently the CDC vastly overstated the effectiveness of flu vaccines, then sharply (and quietly) downgraded its assessment (from 70-90% to 50-70%) only after it learned about the impending publication of The Lancet study.
Last week The Washington Post reported that a working group of the National Biodefense Science Board has advocated “inject[ing] healthy children with the anthrax vaccine to see whether the shots would safely protect them against a bioterrorism attack.” The recommendation is controversial because the risk of children being exposed to anthrax in a terrorist attack is speculative, and there is a dispute among researchers about the safety of the vaccine. In light of that dispute, it is doubtful researchers could demonstrate that children participating in this research would not be subjected to more than minimal risk, or that the risk is justified by the potential benefits to these children, as is generally required by the regulations governing federally-funded research on human subjects. (At a more practical level, the proposed research also raises the question of what parents would volunteer their children to participate in this study. As a father of two, I’m not exactly jumping at this opportunity.)
Perhaps most controversially, last Tuesday The New York Times ran a front-page story on a recommendation by the CDC’s Advisory Committee on Immunization Practices that boys and young men should be vaccinated against human papillomavirus (HPV), a sexually-transmitted disease. If some people recoiled at the idea of giving the HPV vaccine to pre-teen girls (perhaps on the assumption that their own daughters would be chaste), it’s reasonable to expect an even more visceral response to the idea that young boys should receive the vaccine – particularly because HPV-related complications in men are most common among those who engage in homosexual conduct.
I’m not in a position to second-guess the Advisory Committee’s HPV recommendation, but I suspect the argument against it would run something like this: According to The Kinsey Institute, roughly 4-6% of American males have ever had same-sex contact. Among those who do, most never develop HPV-related health problems. Each year the total number of American men who develop HPV-related cancer is about 1,900, or approximately .0006% of the population. While studies performed to date have not identified any serious health risks from the HPV vaccine, there are no published studies of its long-term side effects. In sum, would you vaccinate your young son, without knowing the long-term risks of the vaccine, to guard against the possibility that he will later have sex with other men, and contract HPV, and develop an HPV-related cancer? Some parents might vaccinate their boys for the additional reason that it would prevent them from transmitting the virus to women, who face greater risks from HPV, but I suspect that number would be low.
The prevailing conventional wisdom in the U.S. seems to strongly favor the rapid adoption of new vaccines. No doubt much of this enthusiasm stems from the history of successful vaccination campaigns and reasonable assessments of the relative risks and benefits offered by new vaccines. However, some of it may also be fueled by backlash against anti-vaccine advocates who make alarming claims that appear to lack any scientific basis. Some of the enthusiasm may also be driven by Americans’ unbounded faith in science, which can often lead (particularly within the scientific community) to a bias in favor of technology’s anticipated benefits and a downplaying of potential risks.
This bias can be reinforced by public health officials, whose primary interest is promoting the health of populations rather than individuals. Vaccinating an entire population can have a positive impact on public health, even when many individual members of that population are unlikely to benefit from the vaccine – as, for example, in the case of giving the HPV vaccine to boys to prevent them from transmitting the virus to women. If the CDC exaggerated the effectiveness of the flu vaccine, the agency may have been motivated by a compelling interest in maximizing the number of people who choose to be vaccinated – 50-70% protection against the flu is still much better than none, assuming the vaccines’ risks are minimal. But misrepresenting the benefits of vaccines is both unethical and shortsighted. It undermines trust in public health agencies and provides fodder for anti-vaccine advocates.
This problem is compounded when commercial interests are allowed to drive vaccine policy. In 2006-2007, dozens of state legislatures considered bills that would have made the HPV vaccine mandatory for many school-aged girls. Texas Governor Rick Perry went furthest, signing an executive order requiring young girls to receive the vaccine. The tide turned against mandatory HPV vaccination laws when it was discovered that the vaccine’s maker, pharmaceutical giant Merck, had been a driving force behind much of the proposed legislation. While Merck responded to the public backlash by putting its lobbying efforts on hold, the company was back in action last year, donating thousands of dollars to California legislators who supported a bill that allowed children 12 and order to be vaccinated against sexually transmitted diseases without their parents’ consent. Gov. Jerry Brown signed the bill into law last month.
The enormous power of state and federal governments to sacrifice individual liberties in the interest of protecting public health creates a corresponding responsibility to wield that power cautiously and honestly. Fulfilling that obligation requires making sober assessments of vaccines’ risks and benefits — assessments that are free from influence by commercial interests and mindful of the fact that many medical interventions once considered “safe” have later been found to carry unacceptable risks.