Tuesday, November 25, 2008
Sydney Spiesel at Slate.com writes about the wonders of the flu vaccine and argues that a new study from Canada demonstrates that everyone should receive the wonderful shot each year. He writes,
If we're going to give annual flu shots to children from 6 months to 19 years old, the parents of babies, pregnant women, people 50 years and older, and everyone else with a chronic disease, maybe everybody should just get it. Starting in 2000, the Canadian province of Ontario offered free flu shots to everyone older than 6 months. Fortunately for science, though perhaps not for public health, the other Canadian provinces continued to offer the flu vaccine just as we do in the United States—targeted to specific populations, like the very old, the young, and people with chronic disease. This "experiment in nature" gave Canadian public-health researchers a unique opportunity to compare the benefits of universal influenza immunization with targeted policies.
Results: It's slightly dicey business to compare data from Ontario with those of the provinces that didn't enact a universal-immunization policy. Researchers can't be sure that the differences in the rate of immunization actually caused the differences in influenza diagnoses, hospitalization rates, or excess deaths. In fact, during the seven-year period under study, there was improvement in flu-vaccination rates in all the provinces. As a result, influenza statistics everywhere in Canada improved—but they improved a lot more in Ontario than in the rest of Canada. Influenza-associated deaths dropped by 57 percent in the rest of Canada, but they fell by 74 percent in Ontario. Every other statistic about influenza in Canada—flu-related cases seen in emergency rooms, doctors' offices, or hospital admissions—showed exactly the same pattern: Things are significantly better in Ontario. We do need to be a bit skeptical—that difference might, indeed, be due to some other environmental, economic, or educational difference between Ontario and the rest of Canada. But this evidence is the best we have today, and it's probably good enough to serve as a basis for changes in public-health policy. The only Ontario patients who didn't get significant benefit from flu shots were the elderly. As other studies have also shown, it seems as if it's simply harder to give the elderly good protection against flu using our standard methods of immunization, and there is active ongoing research to develop new, more potent vaccines. Meanwhile, we keep giving older people the present vaccine, hoping that at least some will benefit.
Conclusion: The next question is, Can it be done? Judging by the results in Ontario, the answer seems to be "yes" but only by providing newer sites for immunization, more easily available to the public—for instance, schools, stores, airports, train stations, even election polling sites. Should we do it? People afraid of needles are going to hate me for saying this, but yes, I think so. Extrapolating from the Canadian results, I think it is very likely that a policy of universal influenza immunization will lower hospitalization and death rates and even be economically advantageous. But, of course, it's easy for me to say: As a health care provider, I've already gotten my shot this year.