Researchers from Brown University parsed through the records of millions of nursing home residents and found that flu vaccines can help keep elderly residents alive and out of the hospital.
The study, published in the Journal of the American Geriatrics Society, examines whether nursing home residents were more likely to stay flu-free during years when the flu vaccine better matched the strain of influenza that season. Researchers hypostasized that if the elderly truly didn't benefit from flu shots, the rate of death and hospitalizations from the flu would be the same season to season, regardless of the efficacy of the shot that year.
Year to year, the vaccine match rate varied widely for the flu strain A/H3N2. The researchers compared weekly death and flu-related hospitalizations in each flu season between 2000 and 2009 and found that for every percentage point increase in A/H3N2 match rate, deaths each week declined roughly 0.001 and hospitalizations fell by 0.002 per 1,000 nursing home residents.
"This study evidences protection for an elderly population for whom vaccine efficacy has been questioned," said Stefan Gravenstein, MD, one of the study's co-authors. "Annual vaccination is the only way to maximize the benefit of vaccine, no matter what the age."