Washington, July 1 - U.S. health officials are looking beyond tomatoes for the possible cause of a salmonella outbreak in the United States that has sickened 869 people and hospitalized 107 in at least 36 states.
Officials from the U.S. Food and Drug Administration said on Tuesday that they are expanding their investigation to include other types of produce that are often eaten in combination with tomatoes.
"(The FDA) is looking for all possible explanations for why this outbreak is still ongoing," said Dr. David Acheson, associate commissioner for foods for the FDA.
Officials have been faulted by some in the produce industry for the slow pace of their investigation.
Acheson would not reveal what specific produce items are being examined or where they are grown.
The U.S. Centers for Disease Control and Prevention said 179 people have become sick since June 1.
"The general issue is that cases continue to be reported that have relatively recent onsets," said Dr. Robert Tauxe, deputy director of the foodborne, bacterial, and mycotic diseases division of the CDC.
Tauxe said that several of the new cases have been clustered among people who became sick after eating at the same restaurants. The expanded investigation will look closely at these clusters, he said.
Officials have also activated the Food Emergency Response Network (FERN) to expand the number of state and local labs participating in the testing process. Acheson said the FDA is asking labs across the country to join the investigation and expand the volume and types of food they are testing.
Although officials are broadening the scope of their investigation, they said tomatoes continue to be the primary focus. Tauxe said about 80 percent of the sick people questioned in the primary investigation reported becoming ill after eating raw tomatoes.
Acheson said the FDA is also looking at its own systems for investigating the outbreak.
He acknowledged that the process has been slow and that the FDA needs to examine how to avoid similar situations in the future.
Health officials originally linked the outbreak to raw plum, Roma and round tomatoes, and said the message to consumers remains the same. A list of tomato-growing states that have been cleared by health officials is posted on the FDA website.
Salmonella Saintpaul, the strain involved in the outbreak, is rare, CDC officials said. Typically, the CDC sees only about 400 cases of Saintpaul infections in humans each year.
Salmonella can cause fever, diarrhea, nausea, vomiting, and abdominal pain, according to the FDA.