Table 1. Mean annual influenza-related event rates and relative rates comparing post-UIIP to pre-UIIP event rates.

Event	Number of Events per 100,000 Population in Ontario, Mean (95% CI)		Post- vs. Pre-2000 Relative Rate, Mean (95% CI)
	Pre-UIIP	Post-UIIP	Ontario	Other Provinces Combined
Office visits	813.58 (807.90; 819.20)	173.00 (169.90; 176.10)	0.21 (0.21; 0.22)	0.52 (0.51; 0.53)
ED visits	139.57 (137.50; 141.70)	43.57 (42.20; 44.90)	0.31 (0.30; 0.32)	0.69 (0.67; 0.70)
Hospitalizations	33.38 (32.20; 34.60)	8.49 (7.70; 9.30)	0.25 (0.23; 0.28)	0.44 (0.42; 0.46)
Deaths	12.00 (11.05; 12.96)	2.79 (2.15; 3.42)	0.23 (0.18; 0.30)	0.33 (0.28; 0.39)

Source: Kwong [13].

CI, confidence interval; ED, emergency department; UIIP, universal influenza immunization program.