Pig Slaughterhouse Worker Disease Appears in IndianaJan 17, 2008 | Parker Waichman LLP A mysterious disease affecting pig slaughterhouse workers appears to be spreading. Indiana slaughterhouse workers became ill with symptoms similar to an outbreak at the Quality Pork Processors, Inc. slaughterhouse in Minnesota. Those working in the area of the slaughterhouse where compressed air is used to remove pig brains, have neurological symptoms similar to those involved in the Minnesota outbreak, federal health officials said Wednesday. The employees who became ill in both slaughterhouses, worked in an area on the killing floors' known at the "head tables," where the animals' heads are processed, Centers for Disease Control and Prevention (CDC) spokeswoman Lola Russell said. Both plants use the same method of shooting compressed air into the animals’ skulls to remove their brains, a noisy, smelly, bloody process. The number of those ill in Indiana and the name of the slaughterhouse remains undisclosed. Some scientists suspect inhaled brain matter—turned into mist when compressed—may have triggered the illnesses. "It may be associated with this particular technique of using high-pressure air to remove the pig's brain," Russell said.
The Indiana workers' symptoms included changes in sensation and weakness in their limbs, Russell said, similar to the symptoms reported among the 12 Minnesota workers. In the Minnesota case, health officials suspect workers were exposed to something in the brain tissue that triggered the illness. Officials are continuing to investigate, but so far they haven't identified any viruses or bacteria that could cause the disease. Five of the 12 workers afflicted have been diagnosed with chronic inflammatory demyelinating polyneuropathy, or CIDP, a rare immune disorder that attacks the nerves and produces tingling, numbness, and weakness in the arms and legs, sometimes causing permanent damage. CIDP attacks the lining of the nerves, slowing or blocking the brain’s signals to the muscles; exactly what triggers the attack is unknown. Dr. Kenneth Gorson, a neurologist at St. Elizabeth's Medical Center in Boston, has said that victims can recover fairly quickly if the illness is caught early; however, at least one of the Minnesota workers was told she might never work again. In advanced cases, Gorson said treatment arrests, but does not reverse, the disease. In advanced cases, immune globulin infusions or a plasma-exchange technique are employed to remove antibodies from the blood; another option is the steroid prednisone. Typically, new cases of CIDP occur at the rate of one or two per 100,000 people annually, according the Mayo Clinic. Minnesota state epidemiologist Ruth Lynfield said the discovery of the Indiana illness could help her investigation. "That may help us figure out why these workers are getting sick," she said.
After the Minnesota slaughterhouse illness was reported, the CDC looked into slaughtering practices in 25 large pork processing plants in 13 states, and found only two other plants—one in Indiana, the other in Nebraska—that used compressed air to remove pigs' brains. Minnesota health officials said the pork plants in all three states have voluntarily stopped that practice.
Pork brains are sometimes fried and eaten in sandwiches or with gravy in some areas. But the market is small, and the American Meat Institute, which represents most U.S. pork processors, does not track sales.