|Government scientists struggled Thursday to pinpoint the source of the first U.S. salmonella outbreak linked to peanut butter, the kid favorite packed into millions of lunch boxes every day.
Nearly 300 people in 39 states have fallen ill since August, and federal health investigators said they strongly suspect Peter Pan peanut butter and certain batches of Wal-Mart's Great Value house brand — both manufactured by ConAgra Foods Inc.
How the dangerous germ got into the peanut butter was a mystery. But because peanuts are usually heated to high, germ-killing temperatures during the manufacturing process, government and industry officials said the contamination may have been caused by dirty jars or equipment.
The suspect peanut butter was produced by ConAgra at its only peanut butter plant, in Sylvester, Ga., federal investigators said.
ConAgra said it is not clear how many jars are affected by the recall. But the plant is the sole producer of the nationally distributed Peter Pan brand, and the recall covers all peanut butter — smooth and chunky alike — produced by the plant from May 2006 until now.
"We're talking a lot of jars of peanut butter," said Dr. David Acheson, chief medical officer of the Food and Drug Administration's Center for Food Safety and Applied Nutrition.
About 85 percent of the infected people said they ate peanut butter, and about a quarter of them ate it at least once a day, the CDC's Lynch said. It was the only food that most of the patients had all recently eaten.
Salmonella sickens about 40,000 people a year in the U.S. and kills about 600. It can cause diarrhea, fever, dehydration, abdominal pain and vomiting.
But most cases of salmonella poisoning are caused by undercooked eggs and chicken. The only known salmonella outbreak in peanut butter — in Australia during the mid-1990s — was blamed on unsanitary plant conditions.|