This article examines the association between introduction of Ontario’s Universal Influenza Immunization Program and changes in vaccination rates over time in Ontario, compared with the other provinces combined.

The data are from the 1996/97 National Population Health Survey and the 2000/01 and 2003 Canadian Community Health Survey, both conducted by Statistics Canada.

Cross-tabulations were used to estimate vaccination rates for the total population aged 12 or older, for groups especially vulnerable to the effects of influenza, and by selected socio-demographic variables.  Z tests and multiple logistic regression were used to examine differences between estimates.

Between 1996/97 and 2000/01, the increase in the overall vaccination rate in Ontario was 10 percentage points greater than the increase in the other provinces combined.  Increases in Ontario were particularly pronounced among people who were: younger than 65, more educated, and had a higher household income.  Between 2000/01 and 2003, vaccination rates were stable in Ontario, while rates continued to rise in the other provinces.  Even so, Ontario’s 2003 rates exceeded those in the other provinces.