"That's why we have to concern ourselves with thorough cooking because the infected surface area is ground within the meat," says Michael Doyle, PhD, director of the Center for Food Safety at the University of Georgia.
Doyle says the only way you can know for sure if your hamburger has been cooked to an internal temperature of 160 degrees F. is to use a meat thermometer. "Color is not an absolute indicator."
People may also become infected by eating foods that have come in contact with raw, contaminated meats, poultry, or their juices. Doyle says summer barbecues are common sources of this type of contamination.
"People put raw meat or poultry on a plate, take it out, and cook it on the grill and then put that cooked meat back on the same plate with the raw juices on it," Doyle tells WebMD. Those raw juices can recontaminate any cooked or ready-to-eat foods.
"A good rule of thumb is to consider any raw food of animal origin as potentially contaminated with harmful bacteria," says Doyle. "So handle it properly. Wash your hands after handling it and don't cross-contaminate it with other foods."
The labels on all products subject to the recall bear the establishment code "EST. 969" inside the USDA seal of inspection. All of the ground beef products included in the recall were produced on about 28 different days between April 12 and June 29, 2002. Each product has a packaging date of "APR 12" through "JUN 29" on its label.
The Agriculture Department has not released a list of states involved in the updated recall. The states involved in the initial recall were Alabama, Arizona, California, Colorado, Idaho, Illinois, Iowa, Kansas, Maryland, Michigan, Minnesota, Montana, Nebraska, New Jersey, New Mexico, New York, Tennessee, Texas, Virginia, and Wyoming.
For more information on the recall, including lot numbers and more detailed label information of the recalled items, go to the FSIS portion of the USDA's web site at http://www.fsis.usda.gov/OA/recalls/prelease/pr055-2002.htm.
The last major beef recall of this scope occurred in 1997, when Hudson Beef recalled a record 35 million pounds of meat.