Influenza vaccination in Victoria, 1992

Abstract

Objectives: To determine the rates and patterns of vaccination against influenza in the Victorian population. Further, to determine rates of vaccination against influenza in residents of Victorian nursing homes and hostels.

Design: Between May and June of 1992 we conducted a telephone survey of 537 systematically selected Victorian residents. We obtained information on age, sex, vaccination status, and level of risk for the complications of influenza. We conducted a separate postal survey of 143 randomly selected Victorian nursing homes and hostels to establish rates of vaccination within these institutions.

Participants: Residents of Victoria listed in the White Pages telephone directories in both metropolitan and rural areas. We made calls during working hours to both residential and business numbers, and spoke to the first person who answered the telephone. Participants in the nursing home survey were the matrons or directors of nursing of randomly chosen facilities in the State, who filled out questionnaires relating to their residents.

Results: The vaccination rate against influenza in the whole population was 13.3%. This and all other figures quoted are adjusted for age, unless otherwise specified. There was a significant difference in vaccination rates between rural (9%) and metropolitan (16%) areas (P < 0.05). Using the National Health and Medical Research Council (NHMRC) guidelines, 29% of the population had at least one indication for vaccination. Of people at low risk for complications of influenza, 7.8% were vaccinated. Of people with one or more specific indications for vaccination, 29.4% were vaccinated. Vaccination rates increased with increasing number of indications and with increasing age, approaching 45% in people over 65 years and 50% in people with three or more indications for vaccination. The postal survey of nursing homes and hostels revealed that a mean of 52% of residents per facility were vaccinated against influenza. This figure varied between 45% in rural facilities and 53% in metropolitan facilities.

Conclusions: We estimate that 550,000 doses of influenza vaccine were used in Victoria in 1992. Approximately 50% of these were given to people at low risk for complications of influenza. These findings highlight the need to target high risk groups for vaccination, reassure the general public, and educate health care professionals.