Influenza Vaccine in HCWs and Mortality of Elderly Patients

Source: Potter J, et al. J Infect Dis 1997;175:1-6.

Potter and colleagues examined the differen- tial benefits of influenza vaccination of geriatric subjects in long-term care facilities and the health care workers (HCWs) who care for them. The authors studied 1059 geriatric residents of 12 long-term care hospitals in 1994-1995. The facilities maintained their usual vaccination policies with regard to their patients: six continued to offer vaccine to their geriatric residents, and six provided vaccination only if it was requested by the patient or his or her family. These hospitals were then randomized for their HCWs to be routinely offered influenza vaccination or no vaccination.

At those six facilities that offered vaccination to their HCWs, 653 out of 1078 (61%) agreed to receive vaccine. Eighty-five percent of patients at three of those facilities received vaccine, whereas only one patient (0.4%) received vaccine at the other three facilities. In those hospitals in which HCWs were not offered vaccination, 92% of patients received vaccine in three of them and none in the remaining facilities.

Vaccination of HCWs was strongly associated with a reduction in patient mortality, which dropped from 17% in those hospitals that did not offer HCWs influenza vaccine to 10% in those that did (OR, 0.56; CI 95%, 0.4-0.8), as well as a significant reduction in influenza-lke illness (OR, 0.57; CI 95%, 0.34-0.94). There was no significant difference in mortality between those hospitals whose patients were offered vaccine and those whose patients were not, although there was a trend for the lowest incidence of influenza-like illness at those sites where HCWs and patients were offered vaccine. While vaccination of geriatric patients, many of whom are debilitated, chronically ill, or malnourished, may not have clinical value, this study provides strong support for the recommendation of the CDC for vaccination of all HCWs in contact with patients at risk for significant morbidity and mortality from influenza.-cak