Air Date: Week of March 21, 1997

Richard Rhodes is author of a new book called Deadly Feasts that discusses the class of diseases known as spongiform encephalapothies. Steve Curwood spoke with Rhodes and asked what his research revealed about how the recent outbreak of Mad Cow disease might have spread.

Transcript

RUDOLPH: In the 1950s a strange illness was discovered by scientist Carlton Guy du Scheck in the cannibalistic New Guinea Foray tribe. The disease, called Kuru, eats holes in the brain, much like the extremely rare disease Kreutzfeld-Jakob. They're both part of a class of diseases called spongiform encephalopathies. In the case of Kuru, the disease is spread by eating infected human flesh. This would be just a fascinating scientific anecdote if it weren't for mad cow disease, an illness that's now turning up in cattle that are fed slaughterhouse byproducts. Richard Rhodes is the author of a new book called Deadly Feasts. Living on Earth's Steve Curwood spoke with Rhodes and asked him how mad cow disease might have spread.

RHODES: About half the weight of a steer isn't made into meat that we eat, but is left as waste and has to be dealt with. The way we deal with that, the way the British deal with that, is to cook up the waste bones and blood and heads and entrails and whatever is left over from slaughtering, cook it up, skim off the fat, dry it, and press it into pellets, and feed it back to the animals as a protein supplement to boost their growth, or, in the case of dairy cattle, to boost their milk production.

CURWOOD: You say that Britain changed its machinery with recycling its offal, or whatever you want to call it.

RHODES: Right.

CURWOOD: What do you think happened?

RHODES: Actually, later studies have indicated that the process would never have been sufficient to kill the disease agent. This stuff can be baked in an oven at 700 degrees for an hour and still be infectious. So the normal processing that involved boiling and steam pressure cooking simply was never enough. Now, where the spongiform disease originally came from, the British thought that it probably was from scrapie from their sheep. That lulled them into a false sense of security, because scrapie's been around for hundreds of years and human beings don't get scrapie from eating lamb and mutton. So they thought well, we've got a problem with our cattle business but we don't necessarily have a public health problem. And they waited two or three years before they installed a ban on the feeding of cattle and sheep waste back to cattle and sheep. That gave the disease agent time to infect the beef that they ate. And that led, presumably, last year, to this sudden and shocking announcement by the British Minister of Health that a cluster of some 10 Kreutzfeld-Jakob cases, deaths, in young people -- Kreutzfeld-Jakob only affects people over 40 normally; it's extremely rare in young people. Suddenly the British had 10 young people between the ages of 18 and 36, as I recall, who had died of Kreutzfeld-Jakob. And when they did the autopsies they found that the brain damage looked exactly like the brain damage in their cattle.

CURWOOD: Do we know that mad cow disease causes Kreutzfeld-Jakob disease in people?

RHODES: Dr. Guy der Scheck and many others in the field believe that the disease in its normal form, Kreutzfeld-Jakob disease, arises spontaneously. The reason they believe that is that it turns up around the world at about the rate of one per million people annually, with no evident pattern of food toxicity or anything else that might give them a reason to think it comes from anywhere else. However, it's also known that these diseases can be transmitted. There was a woman in New York City who had a corneal transplant in 1974, and who died 2 years later of Kreutzfeld-Jakob induced, probably, from the infected cornea. The cornea came from a man who had died of Krueutzfeld-Jakob disease.

CURWOOD: How much did the British government know about this risk before it warned the general public against eating beef?

RHODES: I think there's considerable evidence of at least willful ignorance if not deliberate cover-up on the part of the British government in this whole terrible
disaster.

CURWOOD: A pretty serious charge.

RHODES: Well, the first thing that seems to have happened when the British government faced this problem is that some of the people who had been researching in the field for years were simply shunted aside. The government veterinarians took over, men who really had not done any research at all on their own, who only knew what they'd read in the textbooks. There was a conflict of interest. The government was worried about its cattle industry. Understandably; it was decimated. People stopped buying British beef in England as well as abroad. On the other hand, there were early signs that this might be a problem that affected more species simply than cattle. Animals at the zoo in England, various zoos in England, began dying of what was clearly a spongiform disease, probably because they were fed the same materials as the cattle. Cats, some 60 cats, from eating pet food that was contaminated. These were disturbing early signs that this was a disease that easily jumped the species barrier. And yet, there was constant reassurance on the part of high government officials in England that this disease did not affect humans, that we didn't have anything to worry about. Until the day when they found the cluster of human cases and realized that it did. The British performed, the British government really, performed a terrible natural experiment non its population, allowing these disease agents to circulate in the meat supply long enough for who knows how many people to have been infected. Given the long, silent incubation period of this disease, it remains to be seen whether there will be only these 15 or so cases that have already turned up. The British government itself, in one estimate, has put the potential for the epidemic as high as 35,000 deaths, so the word plague that I use in the book and that has been questioned at least by 1 or 2 reviewers is a valid term to describe the potential for this epidemic.

CURWOOD: Are there signs of any other Kreutzfeld-Jakob clusters of disease in other countries?

RHODES: Two French patients have died of this new variant form of Kreutzfeld-Jakob disease. British beef was shipped all over Europe. British protein supplement was shipped all over Europe. In fact, when the British government banned the feeding of protein supplement to cattle in England, they shipped the stuff abroad to France and other countries in Europe. One of the government officials was quoted as saying, "I said this is immoral and I was told in no uncertain terms that that was those other countries' problem, not ours." So yes, the disease -- mad cow disease, first of all, has turned up in various European countries, including Switzerland.

CURWOOD: The United States?

RHODES: No. The CDC very carefully looked at the record of Kreutzfeld-Jakob in the United States recently, going back to 1979, and they found no new pattern other than the standard pattern of about 1 in a million seemingly at random around the world. So there's no evidence that we have had the new form of Kreutzfeld-Jakob disease over here. There is, however, compelling evidence that we have a native form of mad cow disease in our cattle at a low level, and we wouldn't really have much to worry about from that low level of disease, but we also recycle slaughterhouse wastes and feed them to our animals. So the mechanism is in place here, as it was in England, to amplify a low level of the disease into a major epidemic.

RUDOLPH: Richard Rhodes is the author of Deadly Feasts: Tracking the Terrifying Secrets of a New Plague. He spoke with Living on Earth's Steve Curwood.