Cause still sought in 42-state Salmonella outbreak

Robert Roos

Jan 8, 2009 (CIDRAP News) A Salmonella outbreak that was first publicized this week has expanded to 388 cases in 42 states, but the cause remains unknown, the Centers for Disease Control and Prevention (CDC) said today.

News reports yesterday put the outbreak, involving Salmonella enterica serotype Typhimurium, at 336 cases in 34 states.

An online newspaper report yesterday that said the CDC had activated its emergency network to investigate the outbreak was incorrect, CDC spokeswoman Lola Russell told CIDRAP News today. She also said a report that chicken was suspected as the source of the outbreak was wrong.

"We're not in emergency status with this," Russell said. As for the source, she added, "We dont know what it is yet. It would be very premature to indicate that it's chicken or anything else."

In an online statement posted this afternoon, the CDC said that, on the basis of 372 patients with available information, illnesses began between Sep 3 and Dec 29, with most of them starting after Oct 1. Patients range in age from younger than 1 year to 103 years. Of patients for whom information was available, 18% were hospitalized. The CDC did not give a list of affected states.

Of 30 cases identified in Minnesota, 11 patients were hospitalized, and 10 patients were in nursing homes, said Doug Schultz, a spokesman for the Minnesota Department of Health (MDH) in St. Paul.

"We had one death that may be associated with the outbreak," Schultz added. The patient was a woman in her 70s who had "many other health conditions, so we don't know to what extent the Salmonella infection contributed" to her death, he said.

Media reports have mentioned 51 cases in California, 50 in Ohio, and 20 in Michigan.

The CDC said it is collaborating with health officials from many states, the US Department of Agriculture, and the Food and Drug Administration to investigate the outbreak.

The outbreak appears to be the largest Salmonella eruption since the Salmonella Saintpaul episode of last spring and summer, which involved more than 1,400 cases in 43 states. Tomatoes were initially suspected as the cause, but investigators eventually determined that hot peppers from Mexico were to blame.

Most people infected with Salmonella start experiencing diarrhea, fever, and cramps between 12 and 72 hours afterward and remain sick for 4 to 7 days, according to the CDC. Most recover without treatment, but severe cases can occur in infants, the elderly, and people with weakened immunity.