Second Salmonella strain cited in growing tuna-linked outbreak

Robert Roos

Apr 26, 2012 (CIRAP News) – A second strain of Salmonella has been identified in a 21-state outbreak with a contaminated tuna product as the likely cause, and the total number of cases has jumped to 200, the Centers for Disease Control and Prevention (CDC) announced today.

The CDC's previous update on the Salmonella Bareilly outbreak listed 160 cases; today's announcement put the number at 190. In addition, 10 cases of Salmonella serotype Nchanga in five states are now classified as part of the same outbreak, and the CDC has merged what were previously separate investigations, the statement said.

The states with Salmonella Nchanga cases are Georgia (2), New Jersey (1), New York (5), Virginia (1), and Wisconsin (1), the CDC said. All those states also have had Salmonella Bareilly cases in the outbreak.

Overall, of 153 patients with available information, 28 have been hospitalized, but none have died, the CDC said. The latest illness onset date is Apr 12.

The Food and Drug Administration (FDA) found Salmonella Bareilly in two samples of Nakaochi Scrape yellowfin tuna with a pulsed-field gel electrophoresis (PFGE) pattern matching the outbreak strain. In addition, "One of the samples also yielded another type of Salmonella with a PFGE pattern indistinguishable from the cluster of Salmonella Nchanga infections," the CDC said.

The tuna product was distributed by Moon Marine Corp. of Cupertino, Calif., which has recalled it. Nakaochi Scrape is used in sushi, sashimi, and similar products sold in restaurants and stores.

The CDC said Salmonella Nchanga is extremely rare in the United States. Illness onset dates for the 10 cases ranged from Feb 19 to Apr 5. Just one person was reported as being hospitalized, out of six whose information was available.

Wisconsin officials announced yesterday that they had isolated Salmonella Bareilly from one sample of recalled tuna and from a spicy tuna roll made with recalled tuna.