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Volume 22, Number 3—March 2016

Encephalitis, Ontario, Canada, 2002–2013

Alyssa S. Parpia1, Ye Li, Cynthia Chen, Badal Dhar, and Natasha S. CrowcroftComments to Author 
Author affiliations: Public Health Ontario, Toronto, Ontario, Canada (A.S. Parpia, Y. Li, C. Chen, B. Dhar, N.S. Crowcroft); University of Toronto, Toronto (A.S. Parpia, Y. Li, N.S. Crowcroft)

Main Article

Table 3

Univariable and multivariable negative binomial regression model assessing variation in incident encephalitis hospitalizations, Ontario, Canada, and England*

Variable No. (%) cases, N = 6,463 Incidence rate Multivariable analysis
Ontario, 2002–2013
England, 2005–2009†
Adjusted IRR (95% CI) p value Adjusted IRR (95% CI) p value
M 3,417 (52.8) 4.6 Referent <0.0001 Referent 0.002
3,046 (47.1)
0.9 (0.8–0.9)

0.9 (0.9–1.0)

Age group, y
<1 173 (2.7) 10.7 3.9 (3.3–4.5) <0.0001 3.7 (3.2–4.2) <0.001
1–4 377 (5.8) 5.7 2.1 (1.8–2.3) 1.9 (1.7–2.1)
5–19 915 (14.2) 3.2 1.2 (1.1–1.3) 0.9 (0.8–1.0)
20–44 1,486 (23.0) 2.8 Referent Referent
45–64 1,823 (28.2) 4.4 1.6 (1.5–1.8) 1.4 (1.3–1.5)
>65 1,689 (26.1) 8.3 3.0 (2.8–3.2) 1.9 ( 1.8–2.1)

*Incidence is number of cases/100,000 persons. IRR, incident rate ratio.
†Reference (1).

Main Article

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Main Article

1Current affiliation: Yale School of Public Health, New Haven, Connecticut, USA.

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