Improving influenza vaccination rates for high-risk inpatients

In 1987, the Minneapolis Veterans Affairs Medical Center implemented an ongoing, multifaceted influenza vaccination program that targeted all high-risk outpatients followed at the medical center. While the program achieved and sustained vaccination rates of 60% or more for high-risk outpatients, vaccination rates for high-risk inpatients continued to be 25% or less. Beginning with the 1989-1990 immunization season, the "flu shot" program was extended to include all high-risk inpatients. Both the outpatient and inpatient components of the Minneapolis Flu Shot Program emphasized administrative and organizational elements. The program's goal was to achieve vaccination rates of at least 60% for both high-risk outpatients and inpatients. This study assesses the effectiveness of the inpatient program among elderly patients hospitalized on the medical service during the immunization season.

To estimate patient risk characteristics and vaccination rates, 50% of elderly patients who were discharged from the medical service during the immunization season were surveyed using a validated postcard questionnaire. Their responses were compared with the responses of elderly patients to the annual outpatient survey conducted to assess the "flu shot" program.

Overall, 78.6% of elderly respondents discharged from the medical service during the immunization season were vaccinated. Vaccination rates within various high-risk subgroups all exceeded 70%. None of these vaccination rates for inpatient groups differed significantly from the rates for corresponding outpatients.

An outpatient "flu shot" program that emphasizes administrative and organizational elements can be successfully expanded to high-risk inpatients. The vaccination rates attained with such a program may not only achieve but exceed the national health objective for influenza vaccination.