Salmonella Enterica Serotype Paratyphi B Var. Java Gastroenteritis Outbreak Associated with Unpasteurized Tempeh — North Carolina, 2012

BACKGROUND: On March 30, 2012, the North Carolina Division of Public Health (NCDPH) was notified by the state laboratory of five Salmonella enterica serotype Paratyphi B var. Java infections among residents of County A with a novel pulsed-field gel electrophoresis (PFGE) pattern. Although Salmonella is a leading cause of foodborne illness, only 1.1% of Salmonella isolates are serotype Paratyphi B var. Java.  We investigated to identify the vehicle and prevent further illnesses.

METHODS: We defined a confirmed case as laboratory-confirmed Salmonella Paratyphi B var. Java with the outbreak PFGE pattern (outbreak strain) and a probable case as gastroenteritis in an epidemiologically linked person. We reviewed PulseNet data and 89 case report forms, identified frequent exposures, and reinterviewed 41 patients for exposure to frequently implicated food items and restaurants. We conducted restaurant site visits and reviewed product invoices.

RESULTS: We identified 89 cases (87 confirmed, 2 probable) in 5 states with illness onsets during February 29–May 8. Median age was 26 years (range: 4–74 years); 8 (9%) had been hospitalized; and none died. Eighty-three (93%) reported travel to County A. Among 41 patients interviewed, 18 (44%) reported consuming unpasteurized Brand A tempeh; all reported visiting establishments where Brand A Tempeh, originating from a common, local producer, was served. The outbreak strain was identified in samples of Brand A Tempeh and the mold ingredient used for fermentation. We observed inconsistent hand hygiene and preparation of unpasteurized, uncooked tempeh on shared surfaces at the implicated restaurants.

CONCLUSIONS: This is the first reported outbreak caused by exposure to contaminated unpasteurized tempeh. Consistent hand hygiene and separation of uncooked tempeh from ready-to-eat foods should be encouraged.