There is an apparent discrepancy between last week's Lancet Infectious Diseases review article -- which asserted that the lifesaving benefits of influenza (flu) vaccination in the elderly was overstated -- and today's New England Journal of Medicine multicenter study of the extent of mortality benefit over a ten-year period -- which found that the death rate was substantially reduced among seniors who got the vaccine.
It is to be hoped that the media will not take the alarmist view and accentuate the negative by downplaying the role of flu vaccination in reducing the death toll among our over-sixty-five population. The earlier review paper, by vaccine experts from the NIH, George Washington University School of Public Health, and others, merely pointed out that some of the claims of benefits may have been exaggerated by researchers who failed to take certain biases and confounders into account in their analyses. The conclusions of that article emphasized that better-controlled studies, evaluating the real efficacy of flu vaccine in the elderly, are needed before we can accurately say how beneficial the vaccinations are in saving lives. Indeed, the authors conclude by re-affirming the policy we now have: seniors should keep on getting their flu shots. Even if the death-rate benefit isn't actually 50%, as some have claimed, it's certainly well above zero, and the vaccine is almost 100% safe.
Today's NEJM study gives much support to our current public health policy, to strive for total vaccination of the elderly -- by which we now include folks of fifty years and older, which doesn't seem so old to me anymore. The authors, from the University of Minnesota, reviewed vaccination records and hospitalization records for influenza and pneumonia, as well as death records, for several HMOs in three different regions (twenty different cohorts) over a ten-year period, thereby amassing data from over 700,000 person-seasons. They found that among those vaccinated against the flu, there was a 27% reduction in hospitalization for pneumonia or influenza, and a 48% reduction in death rate. Even after they did further controlling for various confounders, they were left with a 7% hospitalization benefit, and a 33% death-rate decline -- and these were the worst-case scenarios for bias and unrelated factors (confounders).
Who Should Get Vaccinated
The take-home message: seniors should keep on getting their flu shots each year, and right around now is the best time -- but better late than never. Even if the benefits are not as great as some have thought, the toll of influenza amounts to about 36,000 dead each year, 75% of whom are over sixty-five. So, any benefit is welcome indeed.
Other groups should get vaccinated as well: children aged six months to five years, pregnant women, anyone with a chronic medical condition or who is immunocompromised, and people who reside in nursing homes or chronic care facilities. Also, household contacts of such people should be immunized. A group whose compliance with the recommendations is poor, and should not be, is healthcare workers. If an older person doesn't get exposed to the flu virus, he or she won't get sick. But this group often sees healthcare workers, so to protect their elderly patients, this group needs to increase its currently abysmal record of getting vaccinated. Also, if more school-age children were vaccinated, they would be much less likely to bring the infection home to their grandparents.
So listen up: don't fall for the superficial story and skip this life-saving shot. Just because we don't know exactly how effective the vaccine is in the older population is no reason to take a chance with your health, or your life.