Fewer flu outbreaks for nursing homes with vaccinated workers, study reports
Problems with this year's flu shot have contributed to a bad season.
The study confirms previous studies and Centers for Disease Control and Prevention guidelines that have encouraged vaccinating healthcare workers against influenza. But researchers in this University of Oklahoma study say that, until now, they weren't certain about the extent to which these vaccinations protect residents. Their study, conducted in 75 New Mexico nursing homes, discovered that when between 51% and 75% of direct care workers in a facility were vaccinated, the odds of a flu outbreak in that facility decreased by 87%.
However, the researchers, who studied rates for the 2006-2007 and 2007-2008 flu seasons, also found that higher rates of residents who received flu vaccines were associated with a higher probability of flu outbreaks. This was an unexpected finding, they noted.
"While the explanation is likely multi-factorial, we suspect a large factor is that facilities with high resident vaccination rates may over-rely on the direct protection bestowed by vaccinating the residents and under-value the indirect protection bestowed by vaccinating employees," said the study's lead author, Aaron Wendelboa, Ph.D. The study was published in the October issue of Infection Control and Hospital Epidemiology.