Background: In Canada, surveillance systems have highlighted the increasing trend of Salmonella enterica serovar\r\nEnteritidis (S. Enteritidis) human infections. Our study objectives were to evaluate the epidemiology of S. Enteritidis\r\ninfections in Ontario using surveillance data from January 1, 2007 through December 31, 2009.\r\nMethods: Annual age-and-sex-adjusted incidence rates (IRs), annual and mean age-adjusted sex-specific IRs, and\r\nmean age-and-sex-adjusted IRs by public health unit (PHU), were calculated for laboratory-confirmed S. Enteritidis\r\ncases across Ontario using direct standardization. Multivariable Poisson regression with PHU as a random effect was\r\nused to estimate incidence rate ratios (IRRs) of S. Enteritidis infections among years, seasons, age groups, and sexes.\r\nResults: The annual age-and-sex-adjusted IR per 100,000 person-years was 4.4 [95% CI 4.0-4.7] in 2007, and 5.2 [95%\r\nCI 4.8-5.6] in both 2008 and 2009. The annual age-adjusted sex-specific IRs per 100,000 person-years ranged from\r\n4.5 to 5.5 for females and 4.2 to 5.2 for males. The mean age-adjusted sex-specific IR was 5.1 [95% CI 4.8-5.4] for\r\nfemales and 4.8 [95% CI 4.5-5.1] for males. High mean age-and-sex-adjusted IRs (6.001-8.10) were identified in three\r\nwestern PHUs, one northern PHU, and in the City of Toronto. Regression results showed a higher IRR of S. Enteritidis\r\ninfections in 2009 [IRR = 1.18, 95% CI 1.06-1.32; P = 0.003] and 2008 [IRR = 1.17, 95% CI 1.05-1.31; P = 0.005]\r\ncompared to 2007. Compared to the fall season, a higher IRR of S. Enteritidis infections was observed in the spring\r\n[IRR = 1.14, 95% CI 1.01-1.29; P = 0.040]. Children 0ââ?¬â??4 years of age (reference category), followed by children 5ââ?¬â??9\r\nyears of age [IRR = 0.64, 95% CI 0.52-0.78; P < 0.001] had the highest IRRs. Adults = 60 years of age and 40ââ?¬â??49 years\r\nof age [IRR = 0.31, 95% CI 0.26-0.37; P < 0.001] had the lowest IRRs.\r\nConclusions: The study findings suggest that there was an increase in the incidence of S. Enteritidis infections in\r\nOntario from 2007 to 2008ââ?¬â??2009, and indicate seasonal, demographic, and regional differences, which warrant\r\nfurther public health attention.
Loading....