The Atlanta-based Centers for Disease Control, along with public health officials in many states, the Indian Health Service and the U.S. Food and Drug Administration, continue to investigate the source of a multi-state 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 that used interviews comparing foods eaten by ill and well people has identified consumption of raw tomatoes as the likely source.

The specific type and source of tomatoes is under investigation, but the CDC says the data suggest that large tomatoes, including Roma and round red, are the source.

Cherry and grape tomatoes, tomatoes sold on the vine and home-grown tomatoes are not believed to be involved in the outbreak, according to the FDA.

The outbreak has created havoc among growers who were trying to ship tomatoes to the market at the time.

"Until now, the market has been in complete collapse. Crops have remained in fields, packinghouses and in the distribution system," says Reggie Brown, executive vice-president of the Maitland, Fla.-based Florida Tomato Growers Exchange. "The losses are staggering."

Tomatoes originating from 18 Florida counties have since been cleared, bringing a small sigh of relief to some growers.

"This allows us to get Florida tomatoes back into supermarkets and restaurants and to move forward in rebuilding consumer confidence in safe, healthy produce," Brown says. "Our growers are working overtime to get their products back into the marketplace."

Although the FDA has yet to find the source, it has reported that tomatoes from Alabama, Arkansas, California, Florida (18 counties), Georgia, Hawaii, Louisiana, Maine, Maryland, Minnesota, Mississippi, New York, Nebraska, North Carolina, Ohio, Pennsylvania, South Carolina, Tennessee, Texas, West Virginia, Belgium, Canada, the Dominican Republic, Guatemala, Israel, the Netherlands and Puerto Rico are not implicated in the outbreak.

The FDA has reported that tomatoes harvested from Baja, Calif., are allowed for U.S. export if they have a certificate issued by the Secretaria de Fomento Agropecuario del Gobierno del Estado de Baja California (Agency).

Since mid-April, 277 people infected with Salmonella Saintpaul with the same genetic fingerprint have been identified in 28 states and the District of Columbia: Arkansas (2 people), Arizona (19), California (6), Colorado (1), Connecticut (2), Florida (1), Georgia (7), Idaho (3), Illinois (34), Indiana (7), Kansas (8), Kentucky (1), Maryland (1), Michigan (2), Missouri (4), New Mexico (68), New York (2), North Carolina (1), Ohio (3), Oklahoma (4), Oregon (3), Tennessee (4), Texas (68), Utah (2), Virginia (16), Vermont (1), Washington (1), Wisconsin (5), and the District of Columbia (1).

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 202 persons with information available, illnesses began between April 10 and June 5.

Patients range in age from less than 1 year old to 88 years; 46 percent were female. At least 43 persons were hospitalized.

Only three people infected with this strain of Salmonella Saintpaul were identified in the country during the same period in 2007. The previous rarity of this strain and the distribution of illnesses in all U.S. regions suggest that the implicated tomatoes are distributed throughout much of the country.

Most people infected with Salmonella develop diarrhea, fever and abdominal cramps 12 to 72 hours after infection. The illness typically lasts four to seven days.

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