At least 124 people in 12 states have been sickened by salmonella infections from raw poultry likely produced by the poultry firm Foster Farms, government health officials reported late Thursday.

The infections of salmonella Heidelberg have been confirmed during the past eight months, starting June 4, 2012, according to the Centers for Disease Control and Prevention. Most of the illnesses have occurred in Washington, with 56 cases, and Oregon, with 38 cases. About a third of those who became sick have been hospitalized. 

Health officials in Washington and Oregon have identified Foster Farms chicken as the most likely source of the infections in their states, though they haven't identified the specific type or source of the meat. About 80 percent of people who have become ill have reported eating chicken in the week before symptoms began, the CDC said. 

Illnesses have been reported in people from infants to age 94, with a median age of 23. No deaths have been reported. Reports of illnesses appeared to spike in late September, although more infections have continued to be reported during what CDC called a "winter lull" in salmonella. Illnesses detected since Jan. 6 might not yet be included in the count because of reporting lag time.

No recall of any products has been announced. The U.S. Department of Agriculture's Food Safety and Inspection Service is conducting an investigation to determine the source of the infections. 

Foster Farms is a West Coast poultry producer with plants in Oregon, Washington, California and Alabama. Company officials said in a statement that all raw poultry has the potential for salmonella contamination and they urged consumers to follow good safety practices, including cooking chicken thoroughly -- to 165 degrees Fahrenheit -- and avoiding cross-contamination with other foods and surfaces. 

"Since 2005, testing results for salmonella from the USDA-FSIS in the Pacific Northwest have consistently been well below the limits set for raw poultry," the statement said. "This indicates that our Pacific Northwest facilities maintained consistent process control for salmonella. Our facilities have earned and maintained Category 1 classification -- the highest performance category for salmonella safety and control -- for the last seven years."

Most people infected with salmonella develop diarrhea, fever and abdominal cramps 12 to 72 hours after infection. Illness typically lasts four to seven days, and most people recover without treatment. In some people, the diarrhea may be so severe that the patient needs to be hospitalized, the CDC says.

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