A new story in The Atlantic on influenza vaccination is sure to raise the ire of the public health officials now encouraging everyone and their little brother to get flu shots. Titled "Does the Vaccine Matter?" the story questions whether influenza vaccination really works as advertised.
Although the story raises some interesting points, to my mind it has two big flaws. The writers begin by stating that the government's planned defenses against H1N1 flu rely heavily on mass H1N1 vaccination. They then quote scientists who question the ability of seasonal flu vaccine to prevent deaths among the elderly, the group most vulnerable to death from seasonal flu. Their logic seems to be that if the seasonal flu vaccine isn't great at protecting the elderly from death, the H1N1 vaccine won't help anybody, either:
Studies show that young, healthy people mount a glorious immune response to seasonal flu vaccine, and their response reduces their chances of getting the flu and may lessen the severity of symptoms if they do get it. But they aren’t the people who die from seasonal flu. By contrast, the elderly, particularly those over age 70, don’t have a good immune response to vaccine-and they’re the ones who account for most flu deaths.
Here's the problem. The elderly aren't at high risk from H1N1 flu. As the Sacramento Bee reported Wednesday, researchers at UC Davis have found that a long lifetime of exposure to varied strains of influenza leaves the elderly at markedly lower risk from H1N1 infection than other groups. And the Centers for Disease Control reports that most deaths from H1N1 have been in people younger than 65, with 25- to 49-year-olds hardest hit. According to the CDC, only nine percent of H1N1 deaths have been in elderly individuals, whereas they account for 90 percent of seasonal flu deaths.
I'm also mystified that The Atlantic's writers give such cursory treatment to the concept of herd immunity - the idea that immunizing a large number of healthy people will protect those who can’t get vaccinated, or for whom the vaccine would be less effective. (Herd immunity gets four rather parenthetical sentences in a 6,000-word article.)
All in all, a bit strange. I'll be watching with interest for other responses to this story.
