The Buncombe County North Carolina Department of Health received final test results from the North Carolina Department of Public Health laboratory confirming that the unopened bag of culture that was added to the tempeh tested positive for the matching strain of Salmonella Paratyphi B linked to the current disease outbreak. Rockville Maryland Tempeh Online sold the starter culture to Smiling Hara Tempeh, which made the meat substitute in Candler, North Carolina.

The US Food and Drug Administration is already involved in tracing the origin of the ingredient to identify source of contamination as well as the potential for other Salmonella outbreaks in the US.

As of May 10 the County Department of Health reported 58 cases associated with salmonella outbreak. North Carolina Department of Public Health reports 63 cases, which includes cases in North Carolina, South Carolina, Tennessee and New York.