October 3, 1997. Copyright, 1997, Graphic News. All rights 
reserved

Mad cow link to humans

The World Health Organisation has given its full backing to two 
studies published in the science journal Nature which confirm a 
link between bovine spongiform encephalopathy (BSE) in cows and 
the new strain of the human equivalent of BSE, new variant 
Creutzfeldt-Jakob disease (nvCJD) in humans.

The U.N. health-agencyÕs Francois-Xavier Meslin endorsed a study 
in Scotland that shows the best evidence yet that BSE  is 
transmitted to people, but stressed that WHO did not support a 
suggestion in a separate study that eating infected beef was the 
likely cause of the disease in humans.

Researchers led by Dr. Moira E. Bruce of the Institute of Animal 
Health in Edinburgh, injected one set of mice with cow tissue 
infected with mad cow disease and another with brain tissue from 
people afflicted with nvCJD. In a year-long study Dr. BruceÕs 
team found that the symptoms, incubation period and mortality 
period of the disease in both groups of mice were identical, and 
unlike other forms of CJD, indicating the new variant CJD and BSE 
were caused by the same prion agent.

Meslin said BruceÕs study confirmed what scientists had suspected 
since identifying the new strain of CJD in March 1996. ÔWe 
believe this is the strongest evidence we have of the link 
between BSE in cattle and the new variant of CJD in humans.Õ 
But Meslin said eating infected beef is unlikely to be the cause 
of the disease in humans.

ÔThe most likely cause would be eating brain tissues of infected 
cattle or other foodstuff but not beef.Õ He suggested meat pies 
as an example of the kind of food that might contain brain tissue 
rather than beef, which consists of the muscle tissue of cattle.

The European Union imposed a ban on British beef after scientists 
suspected a link between BSE infected cows and CJD. Scientists 
believe that BSE, which first broke out in British herds in 1986, 
was caused by feeding cattle with the carcases of sheep that died 
from scrapie, a related brain disease.

The new research could reignite calls for a public inquiry into 
the handling of the BSE crisis and strengthen the cases of 
victimsÕ families calling for compensation.

Sources: Nature, Reuter