After massive recall, testing at poultry plant implies link to listeriosis outbreak

Oct 15, 2002 (CIDRAP News) – Federal health officials announced today that three environmental samples taken from a Pennsylvania poultry processing plant contained a Listeria strain matching that of patients in the current listeriosis outbreak in the Northeast. The announcement came 3 days after the company expanded its recall of turkey and chicken products from the original 295,000 pounds to a record-setting 27.4 million pounds.

The Centers for Disease Control and Prevention (CDC) said DNA fingerprinting showed that 3 of 25 environmental samples taken at the Wampler Foods plant in Franconia, Pa., contained a Listeria monocytogenes strain matching the outbreak strain. The agency also said that the outbreak now includes 46 cases detected since mid-July, up from 44 cases as of Oct 9.

Wampler, a unit of Pilgrim's Pride, recalled 295,000 pounds of ready-to-eat turkey and chicken products Oct 9 after L monocytogenes was found in a product sample during testing prompted by the outbreak. The strain found in the sample did not match the outbreak strain identified by the CDC. Listeria in one of the 25 environmental samples from the plant matched the strain from the product sample, the CDC said today.

After the product sample tested positive, the US Department of Agriculture's (USDA's) Food Safety and Inspection Service (FSIS) took further product samples and numerous environmental samples from the plant, the FSIS reported in an Oct 12 news release. The finding of Listeria in environmental samples prompted Wampler, a unit of Pilgrim's Pride Corp., to expand its recall to 27.4 million pounds, representing all of Wampler's production from May 1 through Oct 11, company and FSIS officials said. The original recall included only products produced Aug 14.

In Associated Press reports, the expanded recall has been called the largest in USDA history, exceeding a 25 million–pound ground beef recall by Hudson Foods in 1997.

In announcing the expanded recall in an Oct 13 statement, Wampler said it was suspending production at the plant while reviewing its safety program. "We will validate our food safety and sanitation efforts by conducting microbial testing before shipments resume," said Dave Van Hoose, Wampler's chief executive officer.

The Wampler announcement said no listeriosis cases in the recent outbreak have been linked with any of its products. However, the statement added, "Wampler received test results from samples taken in plant floor drains . . . that tested positive for a strain of Listeria similar to the strain identified in the recent Northeastern outbreak. This strain, according to governmental officials, while uncommon, is not uniquely identifiable to a single source." CIDRAP News was unable to reach Wampler officials for further comment in time for this story.

The CDC said the FSIS analyzed the Listeria strains found in the plant samples, and the strains were compared through PulseNet, a network of public health and regulatory laboratories that perform DNA fingerprinting and share the results electronically.

Federal health officials have reported a total of 120 listeriosis cases with 20 deaths in the Northeast in recent months. The CDC said 46 of those have involved the outbreak strain, and strains from another 64 patients in the affected states differ from the outbreak strain. The 46 cases involving the same Listeria strain have caused seven deaths and three miscarriages or stillbirths, according to the CDC.

Wampler officials said the recalled products were sold to retail groceries, delicatessens, and foodservice distributors. The products all bear the establishment code "P-1351" inside the USDA inspection seal.

Andrea McNally, an FSIS spokeswoman, said Wampler officials picked May 1 as the start of the period covered by the recall because it was 60 days before the first listeriosis case occurred.

Consumers with questions about the recall can call Wampler's toll-free hotline at 877-260-7110 or visit the Wampler recall Web site at, the company said.

See also:

CDC's Oct 15 news release

FSIS Oct 12 announcement

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