Italian scientists have found a second form of mad cow disease that more closely resembles the human Creutzfeldt-Jakob Disease than the usual cow form of the illness

The brain-wasting diseases BSE, known as mad cow disease, and human CJD are caused by different forms of mutant proteins called prions. A number of people, mainly in England, have also suffered from what is called variant CJD, a brain disease believed to be acquired by eating meat from infected cows. No Americans have been reported with variant CJD. Now, the team of Italian researchers reports a study of eight cows with mad cow disease found that two of them had brain damage resembling the human victims of CJD. They said the cows were infected with prions that resembled those involved in the standard form of the human disease, called sporadic CJD, not the variant caused by eating infected meat. Salvatore Monaco, lead author of the new study, said the findings may indicate that cattle can also develop a sporadic form of the disease, but it might also be a new foodborne form of the illness. Dr. Paul Brown of the National Institutes of Health said the finding does not indicate an increased threat to humans. If a new form of the disease were affecting humans there should be an increase in the incidence of CJD, said Brown, who was not part of the research team. However, scientists in Europe have studied all cases of sporadic CJD for the last decade and the incidence has not changed, said Brown, an expert in the disease, who works at the National Institute of Neurological Disease and Stroke.