Epidemiology of infant salmonellosis in Michigan: Records of 1995-2001

We conducted an epidemiologic study on the incidence of Salmonella infections and the associated risk factors in children aged <1 in the state of Michigan. Data on laboratory-confirmed cases of salmonellosis from 1995-2001 were abstracted from the records of Michigan Department of Community Health. We computed the incidence of the disease by sex, race, and area of residence and analyzed the relationships between selected demographic characteristics and Salmonella infection using Poisson regression analysis. Based on a total of 690 cases, an overall incidence of 73.3/100,000, with an incidence of 84.3/100,000 in male children and 64.9/100,000 in female children, were found. The final covariate-adjusted Poisson model showed that children aged 1-5 months are at higher risk for salmonellosis compared to children aged 6-11 months (RR: 1.80, CI: 1.54-2.10), African-American children are at higher risk than their Caucasian counterparts (RR: 2.63, CI: 2.16-3.19), and male children more commonly represented among cases (RR: 1.30, CI: 1.12-1.51). These findings should be considered by healthcare authorities in Michigan and in states with similar population demographics to investigate possible risk factors that may be associated with the high incidence of salmonellosis in African-American children and in children <6 months.