It’s that time again. Flu season is upon us, and everywhere we turn — from the family doctor’s office to the nightly news — we are reminded to get our flu shot.
It couldn’t be easier: You can get an influenza vaccine at your favorite neighborhood pharmacy, right along with your toothpaste and shampoo, or at a makeshift stand at the grocery store. At more and more businesses, employees can get one just down the hall from their desks.
During the 2010–2011 influenza season, about half of all children and 41 percent of American adults received flu shots. And health officials are pushing for more. The Centers for Disease Control and Prevention (CDC) “recommends that everyone 6 months of age and older get the annual flu vaccine,” says Joseph Bresee, MD, chief of the Epidemiology Prevention Branch at the CDC’s Influenza Division.
Not all experts agree with this advice, though. An increasing number of researchers, academics and doctors are questioning the scientific basis for an influenza vaccine at all. Some point out that the influenza virus isn’t the cause of most flu-like illness, diminishing the advantage that widespread vaccination confers. Others argue that flu shots don’t work well for the most vulnerable among us, including the elderly, because their immune systems are too weak to respond. The most vocal critics even point to studies showing the influenza vaccine is no better than a placebo.
There’s also a safety concern, since many influenza vaccinations contain toxins such as thimerosal, a preservative containing mercury that was removed from most (but not all) children’s vaccines more than a decade ago.
The rising furor over the influenza vaccine differs from the controversy over most other vaccines because the central argument is not over the risk but rather if it works at all. Defenders insist that widespread vaccination will confer a herd immunity to the general population, protecting the weakest among us, who might actually succumb to influenza if exposed. They say that manufacturing an influenza vaccine year after year keeps the factories primed for the dreaded day a more virulent strain threatens a true pandemic, like the one that killed hundreds of thousands of Americans in 1918. But skeptics label such benefits hypothetical at best, and argue that even the smallest risk or side effect is unacceptable.
Next: Where did influenza come from?