Outbreak of multidrug-resistant Salmonella enterica serotype Newport infections associated with consumption of unpasteurized Mexican-style aged cheese–Illinois, March 2006-April 2007

During March 2006-April 2007, an outbreak of Salmonella enterica serotype Newport infections occurred predominantly among Hispanics in northeastern Illinois. Samples from 85 patients, one sample of Mexican-style aged cheese (cotija) from a local Hispanic grocery store (grocery store A), and milk from a bulk tank on a local dairy farm tested positive for S. Newport and had indistinguishable pulsed-field gel electrophoresis (PFGE) patterns. This report summarizes the investigation into S. Newport infections associated with this outbreak. The findings emphasize the need for regulatory authorities to ensure that dairy products, including Mexican-style cheese, are manufactured and distributed by inspected sources and highlight the need for culturally targeted education of consumers and grocery-store operators regarding risks associated with consuming unpasteurized dairy products.