During June of 1999, both the Washington State Health Department and the Oregon Health Division independently investigated clusters of diarrheal illness attributed to Salmonella serotype muenchen infections in each state. As of July 13, 1999, 15 states and two Canadian provinces had reported 207 confirmed cases associated with this outbreak; additional 91 cases of S. muenchen infection were reported, and were still under investigation. By early July 1999, 85 persons with this illness were identified in Washington State alone.

Epidemiological investigations by the health departments linked the outbreak of this relatively rare strain of Salmonella to unpasteurized orange juice products produced by Sun Orchard, Inc., an Arizona based company. Similar strains of Salmonella were eventually detected in unopened containers of Sun Orchard juice products, and in blenders where smoothies were made. The unpasteurized orange juice was identified as freshly squeezed or fresh orange juice, and was also sold in a frozen form to restaurants and other food retailers.

Sun Orchard voluntarily announced a recall of all of its unpasteurized orange juice product. The FDA issued a nationwide warning to consumers against drinking unpasteurized orange juice products distributed under a variety of brand names by Sun Orchard, Inc. due to the continuing reports of illness related to the product.