Breaking News!!!!

My daughter just sent me a link to the article that was in the Brainerd, MN Dispatch. Those affected are just fortunate that they live so close to Rochester, MN so they could be dx & treated so quickly at Mayo. I live in northern MN, but our newspaper did not cover the article. Here is the link:
[url]http://ap.brainerddispatch.com/pstories/state/mn/20071203/222511160.shtml[/url]

I have tried to look up information concerning this but cannot find anything. I tried to copy and paste the link and it did not work either. Does anyone know anymore about this.

thanks

Sherry

The link didn’t work for me also.

Try this link
[url]http://www.startribune.com/business/12104131.html[/url]

Sue

You can go to [url]www.google.com/alerts[/url] and add this to your e-mail. I get all the articles on GBS whenever they hit the news via my e-mail account. Many are newspaper articles on individuals, but there is also info such as the news story out of Minnesota.
I have found this very informative.
JayDee

Interesting development, as when I contracted the disease some 12 years ago, I was an auditor of feed lots and slaughter houses in Kansas. Probably coincidental, but interesting nonetheless….

You’ve probably all seen by now, but the early diagnoses were wrong and the workers do NOT have CIDP.

So, what did they have ??? Thanks.

Dec. 11: Pork-plant ailment a mystery again
By JOSEPHINE MARCOTTY, Star Tribune

Last update: December 21, 2007 – 1:16 PM

A 12th worker at a pork processing plant in Austin, Minn., appears to have the same mysterious neurological condition identified in 11 others by an ongoing state health department disease investigation.

But health officials have backed away from their earlier identification of the condition as chronic inflammatory demyelinating polyneuropathy, or CIDP. Initially they said that five of the workers had CIDP. After additional testing, officials said that none of the workers fits the precise diagnosis of that extremely rare disease — though the tingling and numbness they experience in their arms and legs are similar to it.

Officials believe the condition is causing the workers neurological problems but at this point it cannot be identified as a known or specific disease.

Last week the Minnesota Department of Health announced it had launched an investigation into a cluster of illnesses in 11 workers at Quality Pork Processors in Austin.

They all worked in the same area — the head table, where workers cut the meat from pig heads and extruded the brain from the skulls with a compressed air system.

Though health officials are looking into all possible causes of the illness, they have focused on the compressed air system, which is used by only a few meat processing plants in the country. The system, which exposes workers to airborne particles of pig blood, tissue and fluids, was implemented around the same time that the workers first started reporting problems last December. The plant has stopped using it and now provides employees with more protective clothing and face masks.

Dr. Daniel Lachance, a neurologist at the Mayo Clinic who is involved in screening the workers, said that preliminary tests conducted last week on the 12th worker indicate she has the same symptoms as the others. She worked in the area under investigation. The evaluation is not yet complete, “but I’m convinced that she has it,” he said. “The preliminary testing is consistent” with the others.

Ruth Lynfield, the state epidemiologist, said that she is not surprised that an additional case turned up and that investigators may yet find even more at the Austin plant or at others. They spent last week talking to hundreds of plant workers and anyone who reported neurological symptoms was referred to the Mayo Clinic for screening. Lachance said that a 13th worker is also going through the evaluation process, but preliminary results are not yet available.

A less-specific diagnosis

Lachance and Lynfield also said that further testing has shown that the workers do not have CIDP, a disease in which the immune system for some unknown reason attacks the protective sheath that surrounds nerves. CIDP is very rare, occurring in about 2 out of 100,000 people, and can often be disabling.

Key to differentiating the condition from CIDP is a characteristic of CIDP involving an interruption or blockage of the electrical signaling in and between nerves, Lachance said. Tests now show that none of the 11 workers has that problem, he said.

They do have damage to the nerve system caused by their immune systems, he said. But at this point it can be categorized generically only as an inflammatory response that is damaging the nerve sheaths, he said.

Two of the 11 have symptoms that are different than the rest, Lachance said. One has problems in the spinal cord, and the other has problems in muscles. The others have symptoms that are more similar, characterized by tingling, numbness, discomfort in arms and legs, and variable amounts of weakness. They also described “a very abrupt sense of fatigue,” he said.

For example, one worker was a regular soccer player until he started experiencing tingling and numbness in his legs. Now he can’t play and even walking up stairs is exhausting, Lachance said.

Mayo doctors are developing a treatment regimen for the workers, he said. Most have not been completely evaluated for treatment, but he expects that with help most will improve.

12/21

Minn. rules out chemical toxins in slaughterhouse illnesses Eds: NewsNow.

ST. PAUL (AP) Minnesota health officials are testing more than 100 workers at a pork processing plant in Austin where a dozen have come down with a mysterious neurological ailment.

Authorities also said Friday that they have ruled out chemical toxins as the cause of the illness.

The 12 workers who show signs of nerve inflammation all worked at the head table, where they cut meat off hogs’ heads and blasted compressed air into the skulls to remove the brains. Their symptoms include muscle weakness and tingling and numbness in the legs and arms.

The working theory is that the sick workers were exposed to something in the brain tissue that triggered their immune systems to attack their own bodies.

The Health Department said it has interviewed about 120 employees, both from the head table and from other parts of the Quality Pork Processors plant. More than 100 agreed to throat swabs and blood draws, and the agency is examining those specimens for any signs of an infection.

Another Update.

Watched on the local news, and it appears there is another plant with the same problem, same situation, same everything, but now in Indiana.

[url]http://wcco.com/health/indiana.slaughterhouse.illness.2.631385.html[/url]

Scott

Feds Probe Slaughterhouse Illness Link

Federal health officials are investigating if there’s a link between illnesses reported by several workers at a pig slaughterhouse in Indiana and those seen recently in workers at a Minnesota pork plant. All the employees work in areas where pigs’ heads have been processed using a technique in which compressed air is shot into their skulls until their brains spill out, Centers for Disease Control and Prevention spokeswoman Lola Russell said.

“It may be associated with this particular technique of using high-pressure air to remove the pig’s brain,” Russell 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 the practice.

The Indiana workers’ symptoms included changes in sensation and weakness in their limbs, Russell said. Those symptoms are similar to a mysterious cluster of neurological symptoms reported last month among 12 workers at a pork slaughterhouse in Austin, Minn.

The number of sick workers in Indiana, details of their conditions, the name of the company and the company’s location were not disclosed.

Elizabeth Hart, a spokeswoman for the Indiana State Department of Health, said she could not comment until a meeting with a state epidemiologist set for Thursday morning.

In the Minnesota case, health officials initially suspect the 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 be causing 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 lasting damage.

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 may never work again.

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.

Written By MARTIGA LOHN

This may be beside the point, but why are people removing pigs brains in a meat processing plant? What is done with them?

I think if you find the answer, it will be a long time before you eat any processed meat products.

You’re not going to believe this…there is a recipe for pigs brains on the internet…[url]http://www.weirdmeat.com/2007/02/pig-brains-at-4am.html[/url]

[ATTACH]1114[/ATTACH]
😮
Mmmmm…don’t they look tasty.
😀

I could not help but be struck by the coincidence here. Today I received my initial package from joining the GBS/CIDP Foundation and I decided to read about GBS, even though I’ve read most of it before and I have CIDP. I noticed in the GBS literature a statement “Many cases developed in people who received the 1976 swine flu vaccine”. So I looked that up on the Internet and found in Wikipedia that there have been a couple of outbreaks, including the one in 1976 in USA and another more recently in the Phillipines.
If history is any indicator, there is potential here that there is in fact some flu-like virus which when blasted out of the pig’s brain becomes airborne and inhaled by the workers in that area. Subsequently, the virus might cause an immune reaction similar to a mild form of GBS.
In my opinion, the investigators should be collecting the information on where the swine came from in days prior to the problem surfacing and going to those farms to test other pigs for virus (even if it means slaughtering some and checking samples of brain tissue). It may not be mad cow disease, but it may be something similar, capable of developing into just as serious an issue.

Or…perhaps we will never hear any more about it. (enter the Twilight zone)

Andrew

I am going to Mayo Clinic In a few weeks. Takes forever to get an appt. I will ask and snoop around a little about this. We use to help cut and wrap pork with friends many years ago. I was Dx May 06. Hoping I find some help at Mayo. Lets alll have a great New Year, Regina

andrew,

good point. take care. be well.

gene gbs 8-99
in numbers there is strength

[I]Another update from the Indianapolis Star:[/I]

Also, I have to wonder whether the initial diagnosis of CIDP, made apparently without any nerve conductivity tests, wasn’t a product of the fact that all the Minnesota workers were sent to Mayo for tests and shortly after routed into the CIDP-specialized center. Interesting stuff.

January 19, 2008

Delphi pork slaughterhouse is site of illnesses similar to ones reported in Minnesota

A pork-processing plant in Delphi, Ind., has been identified as the slaughterhouse where two workers have fallen sick with symptoms resembling those seen in a dozen workers at a Minnesota facility.

The United Food and Commercial Workers International Union on Friday named Indiana Packers Corp. as the site in Indiana where two cases of the neurological illness have been found. Union officials criticized the Indiana State Department of Health for failing to name the plant in question.

“The question is why can’t the Department of Health just say where this is so workers in other places can rest assured that it’s not in their plant,” said Jill Cashen, union spokeswoman.

“We’d like to know that they’re in the right plant, they know where the risk is and they’re going to make sure the risk is removed,” she said.

The Department of Health issued a news release Friday saying all employees at the plant in question have been informed and that the investigation is in “its preliminary stages.”

The statement also said the plant had voluntarily stopped using the high-pressure compressed-air technique to harvest pig brains that may be associated with the sickness.

While department spokeswoman Elizabeth Hart declined to confirm the name of the plant, she did say that only one plant in the state is under investigation.

“This isn’t a big secret,” Hart said. “This is not a public health issue. It’s confined to those workers who use that technique.”

Earlier this week, the health department said that two workers at an Indiana plant had fallen ill with symptoms similar to those seen in the Minnesota workers. The symptoms include changes in sensation and weakness in their limbs.

Indiana Packers president Gary Jacobson said Friday that state health workers have been interviewing employees at his plant and that last week his company suspended its process of harvesting pig brains.

He said the health department has not provided any clinical proof that employees at his plant have illnesses linked to those in Minnesota.

“They’re doing their investigation to find similarities in symptoms,” Jacobson said. “They still don’t have any clinical information of anything in particular.”

Of the plant’s 1,500 employees, Jacobson said, dozens worked in the brain-harvesting area. The plant has used the technique for about 10 to 12 years, he said.

The Minnesota Department of Health is investigating the QPP pork-slaughtering facility in Austin, Minn., where 12 workers, all stationed near the air-compression system, fell ill.

Only three plants in the United States — Indiana Packers, QPP and a facility in Fremont, Neb. — are known to use the technique, said Cashen, whose union represents 250,000 workers in the meat- packing and poultry industries across the country.

Indiana Packers workers are not in the union.

Call Star reporter Shari Rudavsky at (317) 444-6354.

Because of Terry emailing a great article here is a story from on of the links in the articles.

DEPARTMENT OF HEALTH & HUMAN SERVICES
Public Health Service
_________________________________________________________________________________________________
Centers for Disease Control and Prevention (CDC)
1600 Clifton Road, MS A-39
Atlanta, GA 30333
January 17, 2008
American Academy of Neurology
In the fall of 2007, clinicians at the Mayo Clinic in Rochester, Minnesota notified the Minnesota Department of Health of an unusual cluster of 12 patients with inflammatory neuropathy occurring between November 2006 and November 2007 among workers at a pork processing plant in Minnesota. An initial investigation has revealed that they all have worked in the same area of the plant where the heads of the pig are processed. The investigation in Minnesota is ongoing and additional patients have been identified in Indiana, among workers in a similar plant. At this point an etiologic agent has not been identified.
These patients have frequently had illness onset with pain, numbness, and tingling in the extremities. The illness typically progressed with development of relatively symmetric mild to moderate weakness involving predominantly the distal lower limbs. Occasionally, facial weakness has also been observed. They often complain of difficulty with balance (ataxia). Electrodiagnostic testing showed prolonged motor distal latencies and F-wave latencies, minimal sensory nerve conduction abnormality, and evidence of mild denervation of distal muscles on EMG. Of the cases in which cerebrospinal fluid (CSF) has been obtained, all have had elevated CSF protein, with minimal if any pleocytosis (e.g., cytoalbuminologic dissociation). Thoracic and lumbar magnetic resonance imaging has demonstrated mildly thickened nerve roots and contrast enhancement. Time of illness progression ranged from several days to months with severity of illness ranging from mild weakness in most cases to paraplegia in one. Most have had some level of recovery.
Given the apparent close association of these patients with participation in the processing of pig head material, it is possible that similar illnesses are occurring at other pork processing plants. The Centers for Disease Control and Prevention (CDC) is requesting neurologists to provide information about patients who may have developed illnesses similar to that reported by the Mayo Clinic. In particular, neurologists who have diagnosed patients with peripheral neuropathy, myelopathy, or a mixed clinical presentation of peripheral / central (and, more specifically, myelopathic) involvement in persons with exposure to pig butchering or processing during the past year are asked to report this information to their state health department, and contact the CDC at 770-488-7100.

[url]http://www.cnn.com/2008/HEALTH/conditions/02/01/slaughterhouse.illness.ap/index.html[/url]

MINNEAPOLIS, Minnesota (AP) — Investigators are closer to understanding a mysterious illness reported by pork plant workers in Minnesota and Indiana and now have pinned a name on it, officials said.

The Centers for Disease Control and Prevention issued a report Thursday summarizing the investigation so far that gives the condition a name — progressive inflammatory neuropathy.

Minnesota officials said they were broadening their investigation to thousands of former employees at the Quality Pork Processors Inc. plant in Austin, going back a decade to when a powerful compressed air system was installed to remove brain tissue from pig heads.

Investigators have been trying to determine whether pig brain tissue, sprayed into the air as droplets during removal by the compressed air system, was inhaled by workers and made them sick.

If further investigation proves their theories true, they will have identified a rare, new condition that could shed light on a whole family of poorly understood disorders in which the body’s immune system attacks the nerves or the sheath that surrounds them, the Star Tribune reported.

This “could have far-reaching applications in terms of our understanding of the mechanism of disease,” said Ruth Lynfield, Minnesota’s state epidemiologist, who is heading the investigation here.

Since December, 12 meatpackers in Austin, Minnesota, and two at a plant in Indiana have reported fatigue, numbness and tingling in their arms and legs. A few are severely disabled; others have returned to work.

Indiana health officials have declined to discuss the conditions of the affected workers there or say where they were employed, citing patient privacy laws.

All 14 employees worked near powerful compressed air systems that blow brains out of pig heads at what is known as the head table. Both plants have stopped using the process.

Lynfield said investigators are now looking for anyone who has worked near Quality Pork’s head table since 1997. That’s difficult because the plant employs about 1,200 workers, many of them immigrants, and turnover is high.

“But we feel it’s important to look for prior cases,” she said.

Health Library
MayoClinic.com: Health Library
Investigators say they’ve ruled out toxins as a cause, and viruses or bacteria are unlikely because none of the affected workers reported infectious disease symptoms, such as fever, before the onset of their neurological symptoms. That would leave the brain tissue itself.

Experts said the foreign pig tissue may have triggered the workers’ immune system, which then attacked their own neural tissue.

Imaging tests show that many of the affected workers have inflammation in the nerve roots in the bottom half of their spinal cords, said Dr. Daniel Lachance, the Mayo Clinic neurologist who first recognized the cluster of unusual cases.

Experts at the Mayo Clinic and New York’s Columbia University are now trying to devise ways to test pig brain tissue against the immune cells of the sick workers, Lynfield said. It could be months before results are in, she said.

[B]The New York Times has a story about it today. It doesn’t mention the initial CIDP theory, but does give a good, detailed review of what has happened so far and what researchers are doing to find the cause. Also, I find it very interesting that one victim is responding well to IVIG therapy.

Is it still not possible to post links?[/B][url]http://www.nytimes.com/2008/02/05/health/05pork.html?em&ex=1202360400&en=33699230c26763e3&ei=5087%0A[/url]

By DENISE GRADY
Published: February 5, 2008

AUSTIN, Minn. — If you have to come down with a strange disease, this town of 23,000 on the wide-open prairie in southeastern Minnesota is a pretty good place to be. The Mayo Clinic, famous for diagnosing exotic ailments, owns the local medical center and shares some staff with it. Mayo itself is just 40 miles east in Rochester. And when it comes to investigating mysterious outbreaks, Minnesota has one of the strongest health departments and best-equipped laboratories in the country.

When some workers at the plant, which kills and butchers 19,000 hogs a day, developed neurological problems, health officials were called in.
And the disease that confronted doctors at the Austin Medical Center here last fall was strange indeed. Three patients had the same highly unusual set of symptoms: fatigue, pain, weakness, numbness and tingling in the legs and feet.

The patients had something else in common, too: all worked at Quality Pork Processors, a local meatpacking plant.

The disorder seemed to involve nerve damage, but doctors had no idea what was causing it.

At the plant, nurses in the medical department had also begun to notice the same ominous pattern. The three workers had complained to them of “heavy legs,” and the nurses had urged them to see doctors. The nurses knew of a fourth case, too, and they feared that more workers would get sick, that a serious disease might be spreading through the plant.

“We put our heads together and said, ‘Something is out of sorts,’ ” said Carole Bower, the department head.

Austin’s biggest employer is Hormel Foods, maker of Spam, bacon and other processed meats (Austin even has a Spam museum). Quality Pork Processors, which backs onto the Hormel property, kills and butchers 19,000 hogs a day and sends most of them to Hormel. The complex, emitting clouds of steam and a distinctive scent, is easy to find from just about anywhere in town.

Quality Pork is the second biggest employer, with 1,300 employees. Most work eight-hour shifts along a conveyor belt — a disassembly line, basically — carving up a specific part of each carcass. Pay for these line jobs starts at about $11 to $12 an hour. The work is grueling, but the plant is exceptionally clean and the benefits are good, said Richard Morgan, president of the union local. Many of the workers are Hispanic immigrants. Quality Pork’s owner does not allow reporters to enter the plant.

A man whom doctors call the “index case” — the first patient they knew about — got sick in December 2006 and was hospitalized at the Mayo Clinic for about two weeks. His job at Quality Pork was to extract the brains from swine heads.

“He was quite ill and severely affected neurologically, with significant weakness in his legs and loss of function in the lower part of his body,” said Dr. Daniel H. Lachance, a neurologist at Mayo.

Tests showed that the man’s spinal cord was markedly inflamed. The cause seemed to be an autoimmune reaction: his immune system was mistakenly attacking his own nerves as if they were a foreign body or a germ. Doctors could not figure out why it had happened, but the standard treatment for inflammation — a steroid drug — seemed to help. (The patient was not available for interviews.)

Neurological illnesses sometimes defy understanding, Dr. Lachance said, and this seemed to be one of them. At the time, it did not occur to anyone that the problem might be related to the patient’s occupation.

By spring, he went back to his job. But within weeks, he became ill again. Once more, he recovered after a few months and returned to work — only to get sick all over again.

By then, November 2007, other cases had begun to turn up. Ultimately, there were 12 — 6 men and 6 women, ranging in age from 21 to 51. Doctors and the plant owner, realizing they had an outbreak on their hands, had already called in the Minnesota Department of Health, which, in turn, sought help from the federal Centers for Disease Control and Prevention.

Though the outbreak seemed small, the investigation took on urgency because the disease was serious, and health officials worried that it might indicate a new risk to other workers in meatpacking.

“It is important to characterize this because it appears to be a new syndrome, and we don’t truly know how many people may be affected throughout the U.S. or even the world,” said Dr. Jennifer McQuiston, a veterinarian from the disease centers.

In early November, Dr. Aaron DeVries, a health department epidemiologist, visited the plant and combed through medical records. The disease bore no resemblance to mad cow disease or to trichinosis, the notorious parasite infection that comes from eating raw or undercooked pork. Nor did it spread person to person — the workers’ relatives were unaffected — or pose any threat to people who ate pork.

A survey of the workers confirmed what the plant’s nurses had suspected: those who got sick were employed at or near the “head table,” where workers cut the meat off severed hog heads.

On Nov. 28, Dr. DeVries’s boss, Dr. Ruth Lynfield, the state epidemiologist, toured the plant. She and the owner, Kelly Wadding, paid special attention to the head table. Dr. Lynfield became transfixed by one procedure in particular, called “blowing brains.”

As each head reached the end of the table, a worker would insert a metal hose into the foramen magnum, the opening that the spinal cord passes through. High-pressure blasts of compressed air then turned the brain into a slurry that squirted out through the same hole in the skull, often spraying brain tissue around and splattering the hose operator in the process.

Susan Kruse, a former employee, being treated at Austin Medical Center.
The brains were pooled, poured into 10-pound containers and shipped to be sold as food — mostly in China and Korea, where cooks stir-fry them, but also in some parts of the American South, where people like them scrambled up with eggs.

The person blowing brains was separated from the other workers by a plexiglass shield that had enough space under it to allow the heads to ride through on a conveyor belt. There was also enough space for brain tissue to splatter nearby employees.

“You could see aerosolization of brain tissue,” Dr. Lynfield said.

The workers wore hard hats, gloves, lab coats and safety glasses, but many had bare arms, and none had masks or face shields to prevent swallowing or inhaling the mist of brain tissue.

Dr. Lynfield asked Mr. Wadding, “Kelly, what do you think is going on?”

The plant owner watched for a while and said, “Let’s stop harvesting brains.”

Quality Pork halted the procedure that day and ordered face shields for workers at the head table.

Epidemiologists contacted 25 swine slaughterhouses in the United States, and found that only two others used compressed air to extract brains. One, a plant in Nebraska owned by Hormel, has reported no cases. But the other, Indiana Packers in Delphi, Ind., has several possible cases that are being investigated. Both of the other plants, like Quality Pork, have stopped using compressed air.

[B]Second part of New York Times story:[/B]

But why should exposure to hog brains cause illness? And why now, when the compressed air system had been in use in Minnesota since 1998?

At first, health officials thought perhaps the pigs had some new infection that was being transmitted to people by the brain tissue. Sometimes, infections can ignite an immune response in humans that flares out of control, like the condition in the workers. But so far, scores of tests for viruses, bacteria and parasites have found no signs of infection.

As a result, Dr. Lynfield said the investigators had begun leaning toward a seemingly bizarre theory: that exposure to the hog brain itself might have touched off an intense reaction by the immune system, something akin to a giant, out-of-control allergic reaction. Some people might be more susceptible than others, perhaps because of their genetic makeup or their past exposures to animal tissue. The aerosolized brain matter might have been inhaled or swallowed, or might have entered through the eyes, the mucous membranes of the nose or mouth, or breaks in the skin.

“It’s something no one would have anticipated or thought about,” said Dr. Michael Osterholm, an epidemiologist who is working as a consultant for Hormel and Quality Pork. Dr. Osterholm, a professor of public health at the University of Minnesota and the former state epidemiologist, said that no standard for this kind of workplace exposure had ever been set by the government.

But that would still not explain why the condition should suddenly develop now. Investigators are trying to find out whether something changed recently — the air pressure level, for instance — and also whether there actually were cases in the past that just went undetected.

“Clearly, all the answers aren’t in yet,” Dr. Osterholm said. “But it makes biologic sense that what you have here is an inhalation of brain material from these pigs that is eliciting an immunologic reaction.” What may be happening, he said, is “immune mimicry,” meaning that the immune system makes antibodies to fight a foreign substance — something in the hog brains — but the antibodies also attack the person’s nerve tissue because it is so similar to some molecule in hog brains.

“That’s the beauty and the beast of the immune system,” Dr. Osterholm said. “It’s so efficient at keeping foreign objects away, but anytime there’s a close match it turns against us, too.”

Anatomically, pigs are a lot like people. But it is not clear how close a biochemical match there is between pig brain and human nerve tissue.

To find out, the Minnesota health department has asked for help from Dr. Ian Lipkin, an expert at Columbia University on the role of the immune system in neurological diseases. Dr. Lipkin has begun testing blood serum from the Minnesota patients to look for signs of an immune reaction to components of pig brain. And he expects also to study the pig gene for myelin, to see how similar it is to the human one.

“It’s an interesting problem,” Dr. Lipkin said. “I think we can solve it.”

Susan Kruse, who lives in Austin, was stunned by news reports about the outbreak in early December. Ms. Kruse, 37, worked at Quality Pork for 15 years. But for the past year, she has been too sick to work. She had no idea that anyone else from the plant was ill. Nor did she know that her illness might be related to her job.

Her most recent job was “backing heads,” scraping meat from between the vertebrae. Three people per shift did that task, and together would process 9,500 heads in eight or nine hours. Ms. Kruse (pronounced KROO-zee) stood next to the person who used compressed air to blow out the brains. She was often splattered, especially when trainees were learning to operate the air hose.

“I always had brains on my arms,” she said.

She never had trouble with her health until November 2006, when she began having pains in her legs. By February 2007, she could not stand up long enough to do her job. She needed a walker to get around and was being treated at the Mayo Clinic.

“I had no strength to do anything I used to do,” she said. “I just felt like I was being drained out.”

Her immune system had gone haywire and attacked her nerves, primarily in two places: at the points where the nerves emerge from the spinal cord, and in the extremities. The same thing, to varying degrees, was happening to the other patients. Ms. Kruse and the index case — the man who extracted brains — probably had the most severe symptoms, Dr. Lachance said.

Steroids did nothing for Ms. Kruse, so doctors began to treat her every two weeks with IVIG, intravenous immunoglobulin, a blood product that contains antibodies. “It’s kind of like hitting the condition over the head with a sledgehammer,” Dr. Lachance said. “It overwhelms the immune system and neutralizes whatever it is that’s causing the injury.”

The treatments seem to help, Ms. Kruse said. She feels stronger after each one, but the effects wear off. Her doctors expect she will need the therapy at least until September.

Most of the other workers are recovering and some have returned to their jobs, but others, including the index case, are still unable to work. So far, there have been no new cases.

“I cannot say that anyone is completely back to normal,” Dr. Lachance said. “I expect it will take several more months to get a true sense of the course of this illness.”

Dr. Lynfield hopes to find the cause. But she said: “I don’t know that we will have the definitive answer. I suspect we will be able to rule some things out, and will have a sense of whether it seems like it may be due to an autoimmune response. I think we’ll learn a lot, but it may take us a while. It’s a great detective story.”

I am from Pueblo, Colorado and worked at the Trane Co. for ten years. Since I contracted GBS in 2000 and now CIDP I have found a number of people that I used to work with have been diagnosed with various forms of GBS, MS, CIDP and god knows what else. Trane is a commercial water chiller plant and use various chemicals in their manufacturing process that I feel contributed to my contraction of GBS. However, none of this can be proven.