Public health officials continue to investigate a multi-state outbreak of Salmonella Rissen, a very rare type of Salmonella in the United States.

On March 27, 2009, Oregon State Public Health isolated Salmonella Rissen from opened containers of ground white and black pepper collected from a restaurant where one of their case-patients had eaten prior to illness onset.  DNA fingerprinting confirmed that these isolates matched the outbreak strain.  Both the white and black peppers were Lian How brand, manufactured by Union International Food Company in Union City, CA.

Subsequently, it was discovered that Lian How ground white pepper was used by several Asian restaurants where case-patients had reported eating prior to their illness onsets.  This included a restaurant in Nevada where six case-patients had eaten at over a three month period.  Salmonella Rissen with a DNA fingerprint matching the outbreak strain has since been isolated from Lian How white pepper collected from the Nevada restaurant.

There are now 47 confirmed cases of Salmonella Rissen in four states, including California (38), Nevada (4), Oregon (4), and Washington (1). Among persons with available information, three were hospitalized as a direct result of gastrointestinal symptoms.  There have been no deaths.  California reports cases from 16 jurisdictions in Central and Northern California: Santa Clara (6), Sacramento (5), Alameda (4), San Francisco (4), San Mateo (4), Contra Costa (3), San Joaquin (2), Sonoma (2), and 1 each from El Dorado, Humboldt, Madera, Merced, Mono, Napa, Placer, and Santa Cruz.