BEEF UP! THERE'S NO WORRY IN THE USA

Exports of British beef have been stopped, and the European Council is supporting the concept of mass slaughter of all English cattle. At least we can be comforted by the knowledge that the EC will not profit from increased beef sales from the continent to the island.

We all remember the days when viruses were the scapegoat of every undiagnosed illness, "We don't know what it is, ma'am, so it must be a virus." Now, we don't just have bacteria, fungi and viruses to fear as disease causing agents, prions now get into the picture. Prions are believed to be the cause of the cow disease BSE, a similar disease in sheep and goats called scrapie, transmissible mink encephalopathy and "chronic wasting disease" of mule deer and elk.

Human prion diseases include Cruetzfeldt-Jakob, Gerstmann-Straussler-Scheinker syndrome, kuru, and fatal insomnia.

What makes a prion a prion? It is a form of protein. Like viruses, prions attack cells, and do their damage inside the cell. Unlike viruses, they lack RNA and DNA, and, therefore, cannot change the genetic code of the cell. What they can do, though, is just as damaging. They convert normal protein molecules into dangerous ones just by inducing the normal molecules to change their shape. Thus, they can cause disease by inheritance as well as by infection.

BSE is known to be transmitted by the consumption of infected body parts (specifically brains and spinal cords). For example, British cattle were fed sheep leftovers from slaughterhouse processing until 1988. In New Guinea, the Fore Highlanders acquired kuru from cannibalism: They honored the dead by eating their brains. Both practices have since been stopped.

Now, the bottom line: What is the real risk of BSE to humans?

• BSE has never, ever been diagnosed in the United States.
• U.S. Imports of British beef (and beef from all countries where BSE has ever been diagnosed were banned in 1989. >Beef and dairy products are considered to be safe from BSE transmissibility. The World Health Organization does not even consider BSE to be a human health hazard, based on current scientific evidence. Furthermore, studies of persons who work with mad cows, such as veterinarians and butchers, found no increased incidence of cases of CJD. Briton's worries are based on 10 cases (5 of whom are farmers) diagnosed with CJD, despite the lack of evidence correlating BSE with CJD.
• Federal veterinarians are tracing 499 head of cattle imported from Great Britain between 1981 and 1989 (before the ban went into effect) to check their health status. As of January 22, 1996, 116 imports are known to be alive and well, 341 are known to be dead and did not have BSE, 8 have been exported. Thirty four are unaccounted for, but are assumed to be dead based on the ages on their records. >Over 60 veterinary diagnostic labs in the US, including Mississippi's, have participated in the BSE Surveillance Program since 1990. Brain specimens from 42 states from 2,660 cattle exhibiting neurologic disease have been examined. None have shown signs of BSE.

  SOURCES: Journal of the American Veterinary Medical Association, Mississippi Board of Animal Health Veterinary Diagnostic Laboratory and the New Jersey Medical School Dept. of Psychiatry.

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