At 67, Helen Wong hasn't missed her annual flu shot in years. She also hasn't been seriously sick in years. Wong is pretty sure there's a connection between those two facts, and she'll be sharing that conviction this fall with fellow members of her fitness club at the Glassell Park Senior Center, five miles north of downtown Los Angeles.
When it comes to flu vaccination, there are always doubters, says Wong, a resident of Glassell Park and a regular at its senior center. But on Nov. 1, when the center holds its annual flu immunization clinic, Wong expects that many of her peers will line up for the shot.
"I'm finding confidence growing," she says, in the long-advertised benefits of the vaccine for older people -- that it drives down the odds of catching the flu, of developing complications from the illness such as pneumonia, of dying.
Among medical researchers and health professionals, however, confidence in those benefits has turned in the opposite direction. After six decades of steadily expanded use among the elderly, flu vaccination for seniors has come under critical scrutiny in several studies. Collectively, they suggest that for those over 65, flu vaccination may confer fewer benefits than have been widely advertised.
Researchers like Lone Simonsen of George Washington University say that the new skepticism is overdue. The medical profession's wariness should have been piqued by a simple but glaring disconnect, says Simonsen, a former epidemiologist for the National Institute of Allergy and Infectious Diseases: Flu vaccination rates among American seniors have risen more than fourfold over 25 years -- to 65% in 2007. During the same period, however, hospitalization for, and death due to, flu and pneumonia appear to have declined only marginally in the nation's 65-and-over population. It just doesn't add up, she says.
"If I could have it my way, we would start by going back and looking at the basic premise for flu vaccination of seniors," says Simonsen, the author of one of the first studies to question the vaccine's benefits for seniors.
Studies on the effectiveness of flu vaccine in older populations have had a wide range of methodological problems, says Simonsen. But although their weaknesses are varied, their effect is almost invariably skewed in one direction, she says: The studies have produced a view of vaccination that is "is far too rosy."
Since the late 1950s, when flu vaccine became widely available to Americans, a belief in the vaccine's lifesaving benefits for older people has been the cornerstone of the nation's immunization policy, a perennial conclusion of published medical studies and an article of popular faith. Not surprisingly, then, the studies that cast doubt on those benefits have been met with concern and hostility.
"These studies are acknowledged to be less specific. More specific studies show clear evidence of effectiveness in individuals and subpopulations," says Dr. William Schaffner, chairman of Vanderbilt University Medical School's department of preventive medicine and an executive board member of the Infectious Diseases Society of America. Schaffner acknowledges that among those over 70, flu vaccine often produces a weak response. "If we wait for something much better, we are missing the opportunity to provide some protection for people who need it."
Helen Wong says she recognizes that for some fellow seniors, the flu vaccine does not appear to provide the kind of robust protection she believes she has enjoyed.
"I cannot say that it will help everyone in the same way it has helped me," Wong says. Other people her age, she adds, "should also be cautious" and understand that the vaccine will not ward off all sickness. "But I would tell them it has helped me."
Flawed fatality count?
The centers for Disease Control and Prevention estimate that flu kills about 36,000 Americans annually. But while that shocking figure seems straightforward enough, calculating the totals of death by flu is anything but. For most of those counted as flu fatalities, pneumonia -- a frequent complication of flu -- is listed as the cause of death.
For those 65 and older, the lesson is clear: A dose of pneumococcal vaccine is a good way to bolster protection among those at risk of suffering complications of flu. A single dose, says the U.S. Department of Health and Human Services, can protect against 23 types of Streptococcus pneumonia bacteria thought responsible for causing more than 90% of pneumonia cases.