Background: Hospitalization of older adults during the period of influenza vaccination in the fall of each year presents a barrier to immunization against influenza. This study evaluates a program using standing orders for influenza vaccination to increase vaccination rates among hospitalized older adults and to determine the effect of vaccination on readmission rates for influenza-like illness.
Methods: An influenza vaccination program using a standing order policy was implemented to vaccinate all consenting persons 65 years and older prior to hospital discharge. This was a prospective, single center, cohort study in a tertiary care university teaching hospital during an 8-week vaccination period in the fall of 1994 and follow-up during the subsequent influenza season. The vaccination status of each patient was recorded as no vaccination, vaccination received in hospital, or vaccination in the community prior to or after the hospitalization. Hospital vaccination rates were compared with the rate of vaccination of older adults in the community. During the subsequent influenza season, the number of subjects reporting symptoms of influenza-like illness (ILI) or who were readmitted to hospital with influenza-related illness was compared in an analysis of vaccinated versus unvaccinated subjects.
Results: Seven hundred and sixty-one patients were interviewed, and 332 of these individuals had been vaccinated in the community prior to their hospital admission. Of the remaining 429 unvaccinated patients who were eligible for vaccination in the study, 171 were vaccinated in our immunization program, eight were vaccinated in the community after discharge, and 244 were not vaccinated. We were able to increase the absolute vaccination rate by 22%, when compared with community rates, with our immunization program. The number of subjects with ILI symptoms or readmission to hospital was too small to compare the vaccinated to the unvaccinated group in the study.
Conclusions: An inpatient influenza immunization program using a standing order policy was able to target a particularly high-risk subset of persons 65 years and over who might otherwise have not received influenza vaccination.