Food illnesses often sicken hundreds of Americans in a single outbreak, making them the kind of mass-disease events that public health departments were created to detect and combat.

Here are the 10 largest food-poisoning outbreaks reported to the federal Centers for Disease Control and Prevention from Jan. 1, 2000, to Dec. 31, 2004, according to a Scripps Howard News Service study of federal outbreak records. A total of 7,840 adults and children got sick or died.

1. An outbreak of Shigella sonnei bacteria, usually spread through human feces, infected 964 people in seven West Texas counties during a four-month period in 2003. More than 70 percent of the victims were children under 12. The outbreak began as a food-borne illness, but also spread through person-to-person contact.

2. About 950 inmates in the Illinois River Correctional Center got sick after eating roast beef with mashed potatoes and gravy in September 2002. Investigators determined the gravy was contaminated with Clostridium perfringens bacteria.

3. An 886-person outbreak of Shigella flexneri bacteria began at the Shish Kabob Snack Bar in Port Washington, N.Y., and spread to four other restaurants in May 2001. Investigators concluded that an infected worker at a produce-distribution plant had contaminated a shipment of bruised tomatoes.

4. An additional outbreak of Clostridium perfringens bacteria at a Louisiana prison sickened 880 inmates in November 2003. State health officials said the disease was spread by food maintained at improper temperature.

5. A Norovirus outbreak at the Opryland Hotel in Nashville, Tenn., in January 2001 sickened 811 people, six requiring medical care. Despite an extensive investigation, health officials were not able to determine the cause.

6. Watermelon contaminated with beef juice served at a children's buffet at a Sizzler Restaurant in Milwaukee was responsible for spreading E. coli to 736 people in July 2000. One child died. Investigators believe the infection occurred at a meat-packaging plant in Fort Morgan, Colo.

7. A food-borne outbreak affecting 707 people was reported in January 2004 in Texas, according to CDC files. However, Texas health officials said they could find no records of this outbreak. No other information was available.

8. Texas health officials received reports from all over the nation after 700 people fell sick from the Salmonella enteritidis bacteria following a conference at the Wyndham Anatole Hotel in Dallas in March 2002. The outbreak lasted more than five weeks. Investigators eventually identified an infected employee who prepared salsa.

9. A privately managed cafeteria at the St. Louis Children's Hospital was the source of an outbreak of Salmonella javiana that sickened 641 in 2003, according to CDC files. Missouri health officials said their records show that only 324 people were affected. Investigators suspected a food handler who worked the salad bar on the two days of the outbreak was the source of the infection.

10. More than 500 customers of a Pennsylvania Chi-Chi's Mexican restaurant were sickened by Hepatitis A in October 2003 caused by infected raw green onions used to make salsa. Three people died. Investigators failed to identify the exact cause of the infection in the fields where the onions were grown.

— Sruthi Kunnel,

Scripps Howard News Service