A pile of tomatoes is seen on display at a wholesale produce market in Washington, June 12, 2008. Representatives from the U.S. Food and Drug Administration and the Centers for Disease Control and Prevention (CDC) said they are continuing to search for the source of the Salmonella outbreak, after reports of people falling ill from eating Salmonella-tainted tomatoes and that they now have 167 reported cases from 17 states.  (Xinhua/Reuters Photo) Photo Gallery>>>

    LOS ANGELES, June 12 (Xinhua) -- The outbreak of Salmonella-tainted tomato illness spread to six more states, infecting a total number of 228 people, the U. S. Food and Drug Administration (FDA) said on Thursday.

    Six more states -- Florida, Georgia, Missouri, New York, Tennessee and Vermont -- reported illnesses related to the outbreak, bringing the number of affected states to 23, according to the FDA.

    The government learned of five dozen previously unknown cases, bringing the toll from salmonella-tainted tomatoes illnesses to 228, said the FDA.

    No deaths have been attributed to the salmonella. But the Center for Disease Control and Prevention (CDC) for the first time Thursday acknowledged that the salmonella may have been a contributing factor in the cancer-caused death of a 67-year-old Texas man.

    The source of the outbreak was still under investigation and officials also were not sure if all the tainted tomatoes were off the market, the FDA said.

    "As long as we are continuing to see new cases come on board, it is a concern that there are still contaminated tomatoes out there," said the agency's food safety chief, Dr. David Acheson.

    Government officials have said all week they were close to cracking the case, but "maybe we were being too optimistic," Acheson acknowledged.

    On the do-not-eat list are raw red plum, red Roma or red round tomatoes, unless they were grown in specific states or countries that the FDA has cleared because they were not harvesting when the outbreak began or were not selling their tomatoes in places where people got sick.

    Also safe are grape tomatoes, cherry tomatoes and tomatoes sold with the vine still attached. That is not because there is anything biologically safer about those with a vine but because the sick have assured investigators that is not the kind of tomato they ate.

    At least 25 people have been hospitalized during the outbreak, caused by a relatively rare strain of salmonella known as Saintpaul.

    Salmonella is a bacteria that can cause bloody diarrhea in humans. Some 40,000 cases of salmonellosis are reported in the United States each year, although the CDC estimates that, because milder cases are not diagnosed or reported, the actual number of infections may be 30 or more times greater. Approximately 600 people die each year after being infected.