Woman contemplating glass of milk

Cleveland Free Times June 16-22, 1999

LACTOSE INTOLERANT

A scientific debate rages over an unproven theory linking a bacterium in milk to Crohn's disease -- a debilitating intestinal disorder affecting at least four million people worldwide.

BY LISA CHAMBERLAIN


Dr. Rodrick Chiodini went on a treasure hunt. Like most people who embark on an improbable journey, the hunt took over his life, changing it irrevocably. Unlike most treasure hunters, he found what he was looking for.

While working on his Ph.D. in microbiology at the University of Connecticut, Chiodini developed an expertise on a bacterium, Mycobacterium paratuberculosis (Mp), that causes a debilitating intestinal disorder in cattle. The disease in cows, identified more than a century ago by Heinrich Johne, is characterized by diarrhea, excessive weight loss, reduced milk production and ultimately death.

Named after its identifier, Johne's disease (pronounced YO-neez) in cattle is similar to Crohn's disease in humans (pronounced kronz). This chronic inflammatory disease of the gastrointestinal tract also results in severe diarrhea, excessive weight loss and -- for humans, who live a lot longer than cows -- debilitating abdominal pain, rectal bleeding, bowel obstruction, fistulas and abscesses. Chronic Crohn's will likely lead to surgery for removal of inflamed intestine, as well as a lifetime of harsh drug therapy that often doesn't work.

The possibility of a connection between Johne's disease in cattle and a similar gastrointestinal condition in humans had been suggested as early as 1913, but for 70 years, every attempt to locate the bug in human Crohn's patients failed. Despite the negative results, the similarities between Johne's in cattle and Crohn's in humans proved too compelling to ignore.

So in 1981, Chiodini went looking for the elusive bacterium, successfully isolating Mp -- the cause of Johne's disease in cattle -- in the intestine of six people suffering from Crohn's disease. Chiodini's discovery -- seemingly the microbiologist's equivalent of unearthing a buried treasure -- turned out to be a Pandora's box. For the first time, Chiodini's research implicated contaminated milk as a possible cause of a debilitating, sometimes fatal, gastrointestinal disease.

The Crohn's connection

"The public should know that there are a number of medical researchers and veterinary researchers that are concerned about the implications of this organism," says Mike Collins, a doctor of veterinary medicine and microbiology at the University of Wisconsin. Collins has been leading a three-year international study on the possible connection between Mp and Crohn's disease, the results of which are not yet available.

"This organism basically resides in animal populations, mainly ruminants, and it causes a disease in those ruminants that looks very much like Crohn's disease [in humans]. But we don't know what, if any, the consequences are when this organism spills over to the human community. We don't know how that might happen, the frequency or the consequences. But we need to figure this out as quickly as possible. There's sufficient scientific evidence to cause concern."

This seemingly banal statement summarizes a raging, eye-crossing scientific debate among a core group of researchers that has yet to come to the public's attention. The debate over the possibility that a bacterium originating in cows might cause Crohn's disease in humans has fueled merciless professional attacks, closed-door meetings and a lot of behind-the-scenes hand-wringing.

What it has not fueled is well-funded research by either the government or the dairy industry. The little research that has been undertaken has been on shoestring budgets, yielding debatable results. Very few researchers have been able to culture the bug from Crohn's patients, grow it in the laboratory or detect an immunological response to it. Conflicting research has been reported from every corner of the globe. The only certainty in the whole matter is that it is a very controversial, unproven theory.

Critics of the theory then use the inconclusive results to argue against committing serious research dollars to investigating the seemingly well-reasoned hypothesis that a bacterium known to cause disease in cattle -- that is shed live in their milk -- can be transmitted to and cause a similar disease in humans.

But without well-funded research, there are no definitive answers to these vexing questions: Does Mp cause or contribute to Crohn's disease in humans? Does Mp survive the pasteurization process? Is it currently in the retail milk supply? Are our children at risk? And if the answer to any of these questions is even possibly yes, why isn't the American public aware that this is indeed a concern?

Estimates are that between 500,000 and 1 million people in the U.S. have Crohn's disease, and it is spreading rapidly. Approximately 55 Americans, mostly between the ages of 15 and 25, will be diagnosed with this incurable disease every day, and at least half of Crohn's patients will require surgery. All will suffer, mostly in silence due to the embarrassing nature of the symptoms, without any awareness that there may be a connection between their illness and the consumption of dairy products.

Researchers investigating the possibility that Mp causes Crohn's suggest that people may be infected with the organism at a young age, when milk consumption is high. Because it is a known to be a slow-growing organism that probably requires a trigger to cause symptoms -- such as the hormonal changes of adolescence -- people do not come down with the disease until later in life. Further, they believe that there is a genetic predisposition, as the disease has a tendency to run in families. They are quick to point out, however, that even the most infectious agents, such as tuberculosis, only causes disease in one out of approximately 300 people who are exposed to it. So exposure to the bacterium does not necessarily equate with contracting the disease. But despite all the mitigating circumstances, a handful of respected researchers around the world suspect Mp is the main culprit in causing Crohn's disease.

"Crohn's disease has a very spotty distribution in the world," notes Dr. Walter Thayer, an expert on the disease at Rhode Island Hospital who worked with Chiodini to culture Mp from Crohn's patients. "But it's seen only in milk-drinking areas -- Australia, southern Africa, Europe, the United States, Canada, New Zealand. Interestingly, it's not seen in India, where they do drink milk, but they boil it first.

"The other thing, Crohn's disease wasn't really known until the '20s. And there were only a few cases in the literature. Now it's a very common disease. What has happened to dairying in that time? Do you get milk from your local dairy? No. You get it from big conglomerates that buy from local dairies and pool all the milk. I think this is possibly the reason the disease has spread so quickly."

Just as Crohn's disease is increasing in the human population, Johne's disease is spreading among dairy cattle. According to a National Animal Health Monitoring System study conducted in 1996 for the United States Department of Agriculture (USDA), an estimated 22 percent of U.S. dairies are infected with the Johne's organism. Larger herds are more likely to be infected -- about 40 percent of the herds with more than 300 cows had at least a 10 percent infection rate.

According to the same study -- despite both its having been identified more than a hundred years ago and the increasing incidence of the disease in dairy herds, which is costing the industry an estimated $1.5 billion a year -- 45 percent of dairy producers are either unaware of Johne's disease or know little about it. This is perhaps due to the fact that between 1992 and 1996, less than 1 percent of the USDA's National Research Initiative Competitive Grants funding was allocated to Johne's research and/or education. Regardless of any human health consequences this organism may cause, clearly a problem has been allowed to fester.

"It's one of the most economically significant infectious diseases," says Collins about the prevalence of Johne's in the nation's dairy herds. "It has appeared among our dairy cattle and is spreading, and we don't yet have the means, or possibly the will, to stop it.

"Experts agree that [Mp]...is excreted directly into the milk of infected cows...and that it happens before the animal shows signs of [Johne's disease]," says Collins. "The question is whether Mp in raw milk is sufficiently heat-resistant to withstand pasteurization. Four studies indicate that Mp is capable of surviving pasteurization, and two studies say it is not. It was found in pasteurized retail milk in England in 1996," results that were reproduced by Dr. Irene Grant, a respected researcher from Ireland.

Dusting for fingerprints

Shortly after Chiodini reported his successful efforts to cultivate Mp from Crohn's patients, he sent some of these cultures to Dr. John Hermon-Taylor, chairman of the department of surgery at St. Georges Hospital Medical School in London. An internationally recognized expert on Crohn's disease, Hermon-Taylor used these cultures to identify a unique genetic sequence in Mp, known as IS900.

This genetic "fingerprint" was then used by Hermon-Taylor to investigate whether Crohn's patients are more likely to be infected with Mp than other populations. In 1991, Hermon-Taylor reported that 65 percent of Crohn's patients tested positive for the presence IS900 (and thus the presence of Mp), whereas only 4.3 percent of ulcerative colitis patients and 12.5 percent of people without Crohn's disease tested positive.

Hermon-Taylor also received a small amount of funding to test retail milk in Great Britain for the presence of IS900. Between 1990 and 1994, his laboratory reported that 7 percent of the pasteurized milk they tested was positive for the DNA fingerprint of Mp. After culturing the milk for up to three and a half years, Hermon-Taylor says, "16 percent of the retail milk samples that originally tested negative came up with long-term cultures which tested strongly positive." Significantly, the same pasteurization process used in Great Britain is used in the United States.

Due to Hermon-Taylor's work, the British government announced last August -- garnering headline news there but not a word in the American press -- that experts from the Ministry of Agriculture, Fisheries and Food will spend 18 months investigating at least 1,000 samples of all types of milk for the bacterium.

"I've known that this organism is a strong candidate for causing chronic inflammation of the intestine in humans for a long time," says Hermon-Taylor. "But in order to cross a Rubicon that has very substantial implications, I had to be certain and even more certain. I became absolutely certain about three years ago. It's not a question of whether Mp can act as a human pathogen or not. It's a question of does it cause 50 percent of Crohn's disease or 90 percent of Crohn's disease? And my hunch is -- based on the evidence available, and more is needed -- it causes 90 percent."

In addition to the strong correlation between the genetic fingerprint for Mp and people with Crohn's disease, Hermon-Taylor says that when he treats patients with antibiotics known to be effective against mycobacterial infections, between two-thirds and three-quarters of his patients report improvements, some remarkable.

"I've seen people who were without hope get better like magic," says Hermon-Taylor. "I've been a doctor for nearly 40 years, and it's the best thing I've ever seen in clinical medicine."

One such patient who improved dramatically on Hermon-Taylor's antibiotic regimen is Vanessa Buchanon, who, coincidentally, holds a Ph.D. in microbiology. Buchanon, 28, from London, had been diagnosed with Crohn's and was receiving conventional treatment for about a year.

"In December 1997, I was really ill, and it was getting worse. It was then that my mom gave me an article about Hermon-Taylor. ...I phoned up his secretary and [wondered] if I could get treatment. He actually came to the phone and chatted with me for about a half an hour about the research he'd been doing.

"So I started the treatment in April 1998. I was really sick. I'd lost about five kilos in weight [more than ten pounds] and I couldn't eat anything. I had these abscesses in my rear end and was really ill. So I started on the treatment, and it was a rough ride in the first few months, because you get high fevers and general exhaustion. When it got towards the end of June, I suddenly started feeling better and, by the end of July, a lot better. Last year, I was dead; I couldn't do anything at all. Now I lead a perfectly normal life, with the exception of not eating dairy products."

Joe Solek, a 47-year-old dentist from Chicago who was diagnosed with Crohn's disease in July 1997, is also on Hermon-Taylor's antibiotic regimen.

"It's really funny because my internist, the guy who has been doing my colonoscopies since 1986, thinks [the antibiotic regimen] is unnecessary treatment. ...But my last colonoscopy was in December 1998, and he said to me after the procedure, 'Boy, this is very close to normal.' He said if he had to rate my disease on a scale of one to 10, with 10 being the worst, I'm a one. I asked if that was due to the medication, and no one really knows.

"I'm a dentist," continues Solek. "[Because of] the lack of research and clinical trials, I'm surprised I'm doing this. But all I have to lose is money. Is this the placebo effect? I don't know. Why couldn't this theory [of a connection between Mp and Crohn's disease] be the case? Especially in light of the fact that it causes a very similar disease in cows. It's an uphill battle because traditional medicine doesn't think there's a connection."

"Now, of course, the proper way in clinical research is to do a pilot study and expand into a randomized control trial," says Hermon-Taylor, who acknowledges that the results Crohn's patients exhibit from his antibiotic regimen are only a step above anecdotal evidence. "We were actually denied the funding to do a randomized control trial. So I did the best that I could with what I've got." To date, 25 of Hermon-Taylor's grant proposals -- submitted both in the U.S. and Great Britain -- to study Mp and its possible connection to Crohn's have been rejected.

Chiodini lost count of the rejected grant proposals he submitted to the National Institutes of Health, the USDA and the Crohn's and Colitis Foundation of America between 1984 and 1994. He estimates having submitted over two dozen, and not a one was funded. In 1994, he lost his job at Rhode Island Hospital due to a lack of funding and was later thrown out of the building for smoking in a nonsmoking area. On March 25, 1994, the hospital packed up the entire contents of his laboratory and shipped it to an unheated storage space, effectively destroying 10 years worth of research. He has not worked in a laboratory since.

Grassroots activism

Alan Kennedy was on a family vacation at the age of 12 when he fell ill. His symptoms looked like appendicitis. In the course of surgery, the doctor discovered it was not appendicitis he suffered from, but Crohn's disease.

It wasn't until after his second surgery in 1996, almost 20 years later, that Kennedy heard about Hermon-Taylor's work. He traveled from his home in Ireland to Hermon-Taylor's office in London to visit the professor and learn about the possible connection between Mp and Crohn's.

A computer scientist, Kennedy immediately recognized the impact a Web site could have in getting the word out about this theory and the underfunded but important research supporting it. After conducting a six-month exhaustive investigation of the available literature with the help of Hermon-Taylor, Kennedy launched a Web site on March 16, 1997.

Karen Meyer of Temple Terrace, Fla., stumbled onto Kennedy's Web site shortly after it went up. Her son had Crohn's, and she took the information contained there to his doctor, who agreed to prescribed Hermon-Taylor's antibiotic regimen for him.

"About a year after he began the [antibiotic] treatment in May 1997," says Meyer, referring to her son, now 24, who was diagnosed with Crohn's at age 17, "he had to have another surgery, and his surgeon observed substantial healing and said he had never seen anything like it. Since then, my son has experienced rapid weight gain and is doing well.

"It was just so unbelievable to me that nobody was addressing the problem," continues Meyer. "So I began, out of frustration, calling the Department of Agriculture in Florida. I got referred up the line, and I kept getting closed doors, passing the buck, getting bounced from FDA [Food and Drug Administration] to USDA to the Center for Veterinary Medicine. And I never came up with a good answer. There was just no concern whether people are being infected every day. When I heard that this was something that for 15 years could have been dealt with, it seemed too unbelievable to be true."

A situation that seemed unbelievable to Meyer is, in fact, not without precedent. Stomach ulcers had long been thought to be caused by excess stomach acid. In the 1983, an Australian researcher named Barry Marshall proposed that ulcers were caused by a bacterium known as Helicobacter pylori. The theory and Marshall were ridiculed until it was slowly but surely proven true over the next decade. This situation is now cited quite often by researchers who suspect Mp causes or contributes to Crohn's.

But as difficult as it was to convince the medical establishment that a bacterium, not stress, causes ulcers, it was not nearly as controversial as suggesting that contaminated milk might possibly contribute to a debilitating gastrointestinal disease, especially when that disease is thought by a vast majority of the medical community to be an immunological malfunction.

"Once I realized how big this was, I was reluctant to really decide how committed I wanted to be with this," Meyer says. "We had the drugs for my son, I could have stopped there. But I realized, for whatever reason, this dropped into my lap, and I had to have the courage to do what needed to be done. ...A researcher at CDC [Centers for Disease Control] said to me, and I don't want to use his name, 'What I suggest to you, Ms. Meyer, is that you form a grassroots organization and get politically proactive.'"

So she and Kennedy began communicating via e-mail, and Meyer met two other people, Cheryl Miller and Stephen Merkel -- both of whom came upon Kennedy's Web site while researching Crohn's in hopes of providing answers to their loved ones affected by the disease. Together, the four of them formed PARA, or the Paratuberculosis Awareness and Research Association, in October 1997 and launched their own Web site.

"Before, in order to conduct a grassroots effort without the Internet, it would have been impossible," says Meyer. "Through the power of the Internet, we think we're responsible for bringing the researchers together. Before this, hardly any of them were in contact. Now they're communicating."

In addition to linking researchers from all corners of the globe -- including Australia, Ireland, Great Britain and in the United States, Florida, Texas and Massachusetts -- PARA also embarked on a major lobbying effort, questioning the FDA about milk safety and the USDA about efforts to control Johne's disease, and calling for Congressional hearings and legislation. They attended U.S. Animal Health Association meetings, sparring with the head of National Milk Producers Federation. In a word, they have been dogged.

The FDA -- despite four studies that conclude Mp survives the pasteurization process -- insists that milk is safe, relying on the two studies that show Mp does not survive. In a letter dated Feb. 9, 1998, Joseph Smucker, the FDA's milk safety team leader wrote, "After a review of the available literature on this subject, it is the position of FDA that the latest research shows conclusively that commercial pasteurization does indeed eliminate this hazard" (emphasis added).

In another letter to PARA, the FDA writes, "The available information suggests that only low levels of M. paratuberculosis can be expected to be found in raw milk and, because the organism is very slow growing, only low levels can be expected in milk when it is subjected to the pasteurization process," which is described as "designed to be fail safe."

The USDA insists that the agency is doing everything it can with regard to Johne's disease, despite having allocated less than one percent of its grant budget to a problem that is spreading quickly. The USDA also points to having formed the National Johne's Working Group in 1994. Interestingly enough, the executive committee of this working group consists of three people, two of whom are industry representatives: John Adams of the National Milk Producer's Federation and Gary Weber of the National Cattleman's Beef Association.

The leaders of the dairy industry point to the FDA's determination that milk is safe and the considerable scientific debate as to whether or not Mp is even a human pathogen. "From the dairy industry's standpoint," says Chris Galen, a spokesperson for the National Milk Producer's Federation, a lobbying organization based in Arlington, Va., "it's something that bears watching. But at this point, it doesn't really look like there's a direct correlation between the bacteria and Crohn's disease."

When asked if the public should be made aware that a handful of respected researchers around the world are investigating the possibility that there is a connection, Galen responds, "There are people who think aliens are invading the planet and maybe we should be made aware of that too, but most people would probably agree that there isn't a lot of evidence of that.

"I'm using that as a facetious example," continues Galen. "I'm not trying to characterize those people who think there is a definitive link between the Johne's organism and Crohn's disease as people who also believe in little green men. What I'm saying simply is that the preponderance of the scientific evidence at this time does not indicate that there is a link between Mycobacterium paratuberculosis and Crohn's disease in humans."

"The agencies that are responsible for regulating animal industries and food safety are also responsible for promoting those industries," says Kennedy. "So they suffer from CJD – conflicting job description."

"We have been asking that the retail milk supply in the United States be tested for the presence of [Mp], and they [FDA] refuse to do it," says Stephen Merkel of Cleveland, a founding member of PARA, whose wife has suffered with Crohn's disease since 1960. "They insist that this organism does not survive the pasteurization process. If they're so sure, why not test retail milk? I see only one explanation as to why they refuse to test the milk supply -- they are afraid of what they might find."

Despite the repeated beating of their collective head on the proverbial brick wall, PARA achieved a major breakthrough when they successfully lobbied the National Institutes of Health to conduct a workshop on Crohn's disease in December 1998.

"We went out to the NIH and implored them to look at the science," says Cheryl Miller of Dayton, also a founding member of PARA, whose 5'6" daughter was down to 92 pounds before she began taking an antibiotic regimen similar to Hermon-Taylor's, which was followed by her rapid improvement. "The NIH reviewed the science and put on this workshop. The fact that the NIH took this action tells you that a prudent person aware of the available scientific evidence would be very, very concerned."

The research battle

On Dec. 14, 1998, a host of researchers were brought together at NIH in Bethesda, Md., to discuss the possible connection between Mp and Crohn's. Despite the circumstantial evidence that there exists a relationship, it is hardly a forgone conclusion. Among the impressive group of experts presenting evidence of a possible connection, one presenter took the opposing viewpoint.

"If you had talked to me in 1984, I would have given you the same kind of pitch that Mike Collins gave," says Dr. Herbert Van Kruiningen of the University of Connecticut. "I would have shown you a picture of an emaciated cow, an emaciated human with Crohn's, and I would have shown you a picture of the intestine of a cow with Johne's and a human intestine with Crohn's.

"But in the meantime, an awful lot of evidence has come by, and I would be no damn good as an investigator if I didn't accept that evidence from lab after lab after lab. I made a decision a few years ago that I wasn't going to spend the rest of my life chasing Mycobacterium paratuberculosis when all of this evidence is out there that this isn't the correct organism."

Kruiningen -- although at the same time admitting that Crohn's research has been woefully underfunded -- cites examples of researchers' failed attempts, including his own, to establish a connection between Mp and Crohn's.

"When you have low-budget research, you get low-budget results," says Chiodini. "Most scientists appreciate that negative results are easy to achieve. It is the positive results that take effort."

"It's very hard to prove causation," says Collins. "Critics are fair to say it's still just an association. It's a very complicated disease, and it's a very complicated organism to deal with."

Kruiningen, undeterred in his opposition to the theory, wrote to Dr. Dennis Lang, who helped to organize the NIH workshop, shortly afterwards. "I came away [from the Crohn's disease workshop] with the impression that the M. paratuberculosis proponents had carried the day. It appeared that most of the people there were enamored with the interesting hypothesis, to the point that data to the contrary were secondary."

Despite Kruiningen's objection to the theory, the NIH workshop produced a document concluding that research into the possible connection was not only warranted, but necessary. Lang says that a wide net will be cast in looking for a cause of Crohn's, but most of the research recommendations that were made in the NIH document involve various aspects of Mp and its potential to cause Crohn's disease in humans.

Interestingly, every single NIH research recommendation had been made by Chiodini in the form of grant proposals between 1984 and 1994. Yet despite Chiodini's work -- recognized by those in the field as visionary and well-known to the organizers of the workshop -- NIH neglected to invite him to Bethesda. He attended anyway at the behest of the founders of PARA, who paid for his travel expenses.

The politics of medicine

"What you have to realize is that there is a lot of politics in medicine," says Chiodini, who is still unemployed. "It's not whether you have the proof of something, but whether or not the medical community wants to accept it. Any time you don't follow standard thought, you get into trouble."

Chiodini says he conducted a study as early as 1984 to see if Mp survived the pasteurization process and found that it did. He was unable to get these results published for 10 years. He also says that the National Dairy Promotion and Research Board -- the marketing group that promotes dairy consumption with "Got Milk?" ads, which are funded by an assessment on dairy farmers as well as subsidies from the USDA -- has known for some time that there is a possible connection between Mp and Crohn's. He says shortly after his pasteurization study was published in the Journal of Veterinary Diagnostic Investigations, he was called to a Dairy Board roundtable discussion in Chicago on July 8, 1994, on this very topic.

"There were at least a dozen people there to discuss this issue and to see whether or not the dairy industry should be concerned and what they should do," says Chiodini, who provided a memorandum outlining the meeting's agenda. "The panel stated that they should be concerned and gave recommendations on what should be done. To my knowledge, they never did anything."

The Canadian government has also known about a possible connection between Mp and Crohn's since at least 1994. The Food Production and Inspection Branch of Canada's Agriculture Department produced a Food Safety Risk Assessment paper on "Mycobacterium paratuberculosis and Crohn's disease," which concluded that it was indeed a cause for concern. The document was stamped "Protected -- Not for Distribution."

Chiodini also says he knows of pharmaceutical companies that have been working behind the scenes in preparation for the day this theory comes to light. "You'll be amazed at how quickly the pharmaceutical companies will be out with a product to address it. They're calling this another Helicobacter," he says, referring to the oft-cited ulcer analogy. Pharmaceutical companies were caught off guard when the Helicobacter theory proved true, and are making sure that doesn't happen again, says Chiodini. He says he has talked with a number of pharmaceutical companies about what they should be doing to prepare for the possibility that Mp causes Crohn's.

And the evidence continues to mount. On June 1, two teams of researchers -- from Baylor College of Medicine in Houston and the University of Central Florida in Orlando -- announced at an annual meeting of the American Society for Microbiology in Chicago that they had isolated Mp from the tissue of Crohn's patients, but not from control specimens.

"We are not making any claims that all patients with Crohn's have paratuberculosis, because it is my belief that this is a disease of multiple causes," says Dr. Ira Shafran from University of Central Florida, a gastroenterologist originally from Cleveland Heights. "But it is my belief that this microorganism will be proven as a human pathogen and clearly operative in these patients with Crohn's.

"Dr. Chiodini should really have the disease changed to his name," continues Shafran. "This is not Crohn's disease. That is a catch-all name that has been applied to a variety of inflammatory problems, of which paratuberculosis is one. My concern here as a physician and father of two children is that the animal source of this infection is dairy cattle. ...My population [of Crohn's patients] that is being treated with antibiotics, I've warned them of a possible animal source for obtaining the infection, and I don't want them to reinfect themselves. I've told them to look for ultra-pasteurized milk and to cook their meat well."

"Barry Marshall suggested that Helicobacter caused ulcers, and he was ridiculed," says Hermon-Taylor. "And this was a bug that you could see by looking down the microscope, grow in a simple culture system in the lab, test for immunologically pretty simply, and ordinary tablets readily available to doctors could make it go away. And it still took eight years for the penny to drop.

"Now we've got a bug that you can't see, can't grow, hides under the immunological radar, is a bastard to kill, and the problem it's causing is far, far greater. If Rod Chiodini and I are wrong, the magnitude of the problem will only be the economic losses of farm animals, which is costing the U.S. somewhere between $1.5 and $2 billion a year. If Rod Chiodini and I are right, then, oh dear, oh dear. We have a big problem. It's going to take a lot to put it right."

Copyright © 1999
Hummingbird Press