An unusual occurrence of multiple sclerosis in a small rural community.

Ten patients with multiple sclerosis were found to have lived in close proximity in a Nova Scotia farming community of 150 people. All had drunk unpasteurized milk as children, were teetotallers, ate a high animal fat diet, and were well educated. Of greater interest was the observation that six of the ten cases were related in two family groups. The only time all patients lived in the community at the same time was in 1951 and 1952 during a polio outbreak. The relationship of polio to multiple sclerosis bears further study. The average age of the patients when they had measles was 11.8 years. Evidence suggests a link between risk of multiple sclerosis and both late onset of measles and pubertal age. Late onset of measles may be important in this cluster. Further epidemiological studies are needed to examine the age of onset of measles in M.S. cases.