In angry defiance of the anti-immunization hysteria of our times, we took the kids to get their flu shots this afternoon. A recent letter to the editor in our state paper (10/24/07) stated that the flu vaccine contains mercury, "a dangerous neurotoxin." "A week of the flu is miserable, but it only lasts a week," the letter opined. "Mercury buildup in the body can last a lifetime and has been implicated in numerous disorders. Please think twice before allowing this substance to be injected into those you love."
As a person working at a university, where rumors proliferate like weeds and kids will seize on the flimsiest excuses for not taking proper care of themselves, I'm infuriated that the autism-vaccine theory has now expanded its conspiracy theory to include flu shots. For the children this letter writer wants to protect from consequences no reputable medical study has ever confirmed, "a week of the flu" can be more than miserable; it can kill. Children under age 2 who get influenza are at a high risk for hospitalization. Children under 6 who get influenza require more visits to clinics and the emergency room. Infants under 6 months are at extremely high risk of serious complications or even death, and they can't get vaccinated -- so those around them (family and caregivers) should.
And even though the college kids I work around, who always tell me old wives' tales about the shot giving them the flu as a reason not to get vaccinated, aren't likely to die from influenza, for most of them missing a week of class is almost as dire a fate. I have no sympathy for flu sufferers who miss class and are unable to maintain their GPA, if they didn't get the flu shot. For my students, a bad case of the flu can cost them their scholarships and therefore their undergraduate career.
Weigh those consequences -- real ones -- against the purely theoretical risks from thimerosal, the ethylmercury preservative in some flu vaccines. The exposure from flu shots is far less than the threshold set by the EPA for environmental safety, even cumulatively. No large-scale, well-conducted study has found harm from thimerosal. Yet the letter writer would rather see parents risk their children's health from influenza, an actual disease that kills thousands around the world every year and costs millions in health care resources and lost productivity, than get a vaccine that has an ingredient no one's ever proven to be dangerous in this context at these levels.
When Robert Kennedy, Jr. spoke here in September, an audience member asked him about autism and thimerosal during the Q&A. He talked expansively about the dangers, and pulled out a dramatic statistic. Since thimerosal was introduced into childhood vaccines (I believe he mentioned the sixties, although the preservative has been in use in vaccines since the 1930's), autism rates have risen from 1 in 10,000 to 1 in 250 children. There were audible gasps and murmurs around the auditorium at this. I wanted to stand up and shout, "Correlation does not imply causation!" I could claim that since Sputnik was launched, the same rise in autism incidence has occurred; or that since cereals began to be enriched with vitamins, autism rates have soared (to mention something that is kid-specific and ingested). Without studies showing an actual linkage, it's just misdirection and snake oil. And opportunities for comparative studies are not lacking; some Scandinavian countries changed their vaccine manufacturing years ago to eliminate thimerosal, but rates of autism remain at the same levels as the rest of the developed world. Heck, thimerosal was phased out of most of the U.S. vaccine supply starting in 1999, but is the autism rate decreasing?
I'm no blind believer in science. But when it comes down to hysterical "common sense" that weighs unknown risks higher than known ones, vs. medical professionals who've answered the question the only way they know how -- with data, I'll go with the best knowledge we have now. It might turn out to be wrong, but if so, medical science will discover the error, not lobbyists and demagogues.