Consumers should throw away certain jars of Peter Pan and Great Value peanut butter after the spread was linked to a salmonella outbreak that has sickened almost 300 people around the country, ConAgra said.

Lids of jars produced by ConAgra Foods with a product code beginning "2111" can be returned to the company for a refund, the company said.

The salmonella outbreak, which federal health officials said Wednesday has sickened 288 people in 39 states since August, was linked to tainted peanut butter produced by ConAgra at a plant in Sylvester, Ga. How salmonella got into peanut butter is still under investigation, said Dr. Mike Lynch, an epidemiologist at the Centers for Disease Control and Prevention.

ConAgra officials haven't said how much peanut butter is covered in the recall, which it called a precaution. "We are working closely with the FDA to better understand its
concerns, and we will take whatever additional measures are needed to ensure the safety, quality and wholesomeness of our products," spokesman Chris Kircher said.

CDC officials believe the salmonella outbreak to be the nation's first associated with peanut butter. The most cases were reported in New York, Pennsylvania, Virginia, Tennessee and Missouri. About 20 percent of all the ill were hospitalized, and there
were no deaths, Lynch said. About 85 percent of the infected people said they ate peanut butter, CDC officials said.

Salmonella infection is known each year to sicken about 40,000 people in the United States, according to the CDC. Salmonellosis, as the infection is known, kills about 600 people annually.

Symptoms can include diarrhea, fever, dehydration, abdominal pain and vomiting.

The latest outbreak began in August, with no more than two cases reported each day, CDC officials said. Only in the past few days did investigators hone in on peanut butter as a source, Lynch said.

Other states reporting cases are Alaska, Alabama, Arkansas, Arizona, California, Colorado, Connecticut, Georgia, Iowa, Illinois, Indiana, Kansas, Kentucky, Massachusetts, Maryland, Maine, Michigan, Minnesota, Mississippi, Montana, North Carolina, Nebraska, New Jersey, New Mexico, Ohio, Oklahoma, Oregon, South
Carolina, South Dakota, Texas, Vermont, Washington, Wisconsin and West Virginia.

To get a refund, consumers should send lids and their names and addresses to ConAgra Foods, P.O. Box 57078, Irvine, CA 92619-7078. For more information, call 866-344-6970.