CDC reports frozen tuna source of ongoing Salmonella outbreak

A Salmonella outbreak affecting at least 62 people in 11 states has been linked to contact with frozen raw tuna, according to the CDC.

Illnesses related to this outbreak, which were caused by Salmonella Paratyphi B variant L(+) tartrate(+) bacteria, have affected people aged younger than 1 year to 83 years, 56% of whom were male. Onset dates ranged from March 5 to July 7. As of July 22, the CDC has been informed of 11 hospitalizations among those infected.

Initial interviews with outbreak cases suggested recent consumption of sushi made with raw tuna as a potential source of infection. Contamination was detected later in frozen tuna products distributed by Osamu Corp., which announced two voluntary outbreak-related recalls on July 21.

Antibiotic resistance testing conducted on three isolates by the National Antimicrobial Resistance Monitoring System found one isolate that was resistant to ampicillin, while the others were susceptible to all tested antibiotics. Further investigation by public health investigators partnered through PulseNet, a national subtyping network of public health and food regulatory agency laboratories, is still underway, according to the CDC.