Multiple sclerosis may be linked to virus

New evidence emerged yesterday that multiple sclerosis - the progressively disabling disease of the nervous system - is caused by a virus. Traces of several viruses have been found in the brains of people with MS, but the strongest evidence that an infectious agent is involved is the way that the disease sometimes occurs in clusters.

Doctors have discovered a new cluster of eight cases, all emanating from one tiny village, called Fjelso, in Denmark. The eight people, all adults, went to the same elementary school for seven years and were all scouts together. Two were brother and sister and two were aunt and nephew.

Various viruses have been contenders for the `MS virus', but Dr Sven Haahr, of the University of Aarhus, Denmark, and his colleagues, believe it to be the Epstein-Barr virus, which causes amongst other illnesses, glandular fever in adolescents. They plan to investigate the eight patients to see if they have any traces of Epstein-Barr and, if so, if the traces are of the same type, which would make the evidence more convincing. Annabel Ferriman