650 sick and three dead in 2003 linked to hepatitis A-tainted green onions.

In late October 2003, the Pennsylvania State health officials first learned of a potential hepatitis A outbreak from emergency room doctors in Beaver County, Pennsylvania, who reported an unusually high number of hepatitis A cases in late October 2003. Investigators from the health department began investigating the people who had fallen ill and determined that the common thread for all was having eaten at the Chi-Chi’s restaurant at the Beaver Valley Mall. Once the department isolated the restaurant as the probable source of the outbreak, Chi-Chi’s closed the restaurant voluntarily and it remained closed for a number of weeks.  Chi-Chi’s went bankrupt and never reopened.

Ultimately, over 650 confirmed cases, both primary and secondary, were linked to this outbreak. The victims included at least 13 employees of the Chi-Chi’s restaurant, and numerous residents of six other states. Three persons died as a consequence of their hepatitis A illness. In addition, more than 9,000 persons who had eaten at the restaurant during the period of potential exposure, or who had been exposed to ill persons, obtained immune globulin shots as protection against the hepatitis A virus.

The Pennsylvania Department of Health and the federal Centers for Disease Control and Prevention (CDC), along with the U.S. Food and Drug Administration (FDA), conducted further studies investigating the incident. Preliminary analysis of a case-control study indicated green onions were the probable source of this outbreak.

The green onions were typically shipped to the restaurant in boxes, and stored and refrigerated in a bucket of ice. They were eventually chopped up, and utilized in food served at the restaurant, often uncooked, as in the preparation of the mild salsa. “Preliminary trace-back information indicated that the green onions supplied to Chi-Chi’s had been grown in Mexico.”