Outbreak of Infections Caused by Salmonella

WASHINGTON, June 4, 2008 - CDC is collaborating with public health officials in several states, the Indian Health Service, and the U.S. Food and Drug Administration (FDA) to investigate an ongoing multistate outbreak of human Salmonella serotype Saintpaul infections. An epidemiologic investigation conducted by the New Mexico and Texas Departments of Health and the Indian Health Service using interviews comparing foods eaten by ill and well persons has identified consumption of raw tomatoes as the likely source of the illnesses in New Mexico and Texas. The specific type and source of tomatoes is under investigation; however, preliminary data suggest that large tomatoes, including Roma and red round are the source.

Since late April, 57 persons infected with Salmonella Saintpaul with the same genetic fingerprint have been identified in Texas (24 persons) and New Mexico (33 persons). These were identified because clinical laboratories in all states send Salmonella strains from ill persons to their State public health laboratory for characterization.

Among the 38 persons who have been interviewed, illnesses began between April 23 and May 27, 2008. Patients range in age from 3 to 82 years; 48% are female. At least 17 persons were hospitalized. No deaths have been reported.

In addition, 29 persons with the outbreak strain of Salmonella Saintpaul have been reported since mid-April in residents of Arizona (6 persons), Colorado (1), Idaho (2), Illinois (12), Indiana (1), Kansas (3), Utah (1), Virginia (1), and Wisconsin (2). Investigations are underway to determine if consumption of raw tomatoes is also associated with illness in these states.

Clinical features of Salmonella Infection

Most persons infected with Salmonella develop diarrhea, fever, and abdominal cramps 12–72 hours after infection. Infection is usually diagnosed by culture of a stool sample. The illness usually lasts 4 – 7 days. Although most people recover without treatment, severe infections may occur. Infants, elderly persons, and those with impaired immune systems are more likely than others to develop severe illness. When severe infection occurs, Salmonella may spread from the intestines to the bloodstream and then to other body sites, and can cause death. In these severe cases, antibiotic treatment may be necessary.

Advice to consumers

At this time, FDA is advising that consumers in New Mexico and Texas should limit their tomato consumption to cherry tomatoes, grape tomatoes, tomatoes sold with the vine still attached, and tomatoes grown at home. Consumers should be aware that raw tomatoes are often used in the preparation of fresh salsa, guacamole, or pico de gallo, and in tortillas or other food products.

Customers everywhere are advisted to:

• Refrigerate tomatoes within 2 hours or discard cut, peeled, or cooked tomatoes.
• Avoid purchasing bruised or damaged tomatoes and discard any that appear spoiled.
• Thoroughly wash all tomatoes under running water.
• Keep tomatoes that will be consumed raw separate from raw meats, raw seafood, and raw produce items.
• Wash cutting boards, dishes, utensils, and counter tops with hot water and soap when switching between types of food products.