As Federal, State, and Local health agencies continue their investigations into the nationwide Salmonella outbreak recently linked to King Nut brand peanut butter, other products containing the implicated peanut butter may also be linked to the outbreak.

Preliminary analysis of an epidemiologic study conducted by CDC and public health officials in multiple states comparing foods eaten by ill and well persons has suggested peanut butter as a likely source. Ongoing investigations suggest that peanut butter-containing products may also be linked with illnesses. To date, no association has been found with common brands of jars of peanut butter sold in retail grocery stores. 

An epidemiologic investigation by the Minnesota Department of Health has suggested King Nut creamy peanut butter as a likely source of Salmonella infections among many ill persons in Minnesota. The Minnesota Department of Agriculture Laboratory isolated the outbreak strain of Salmonella Typhimurium from an open 5-pound container of King Nut brand creamy peanut butter.

Clusters of infections in several states have been reported in schools and other institutions, such as long-term care facilities and hospitals, and King Nut is the only brand of peanut butter used in those facilities for which we have information.

CDC and other public health officials are continuing to conduct surveillance for cases of infection with the outbreak strain, and to gather and analyze data on exposures to peanut butter and peanut butter-containing products that may be associated with illness.

Two very similar DNA fingerprints of Salmonella serotype Typhimurium have been linked to this outbreak. All ill persons reported as part of this outbreak have had laboratory testing that confirmed infection with a strain that had one of the two outbreak DNA fingerprints.