Until recently poliomyelitis was a rare disease in Northern Rhodesia. In 1943 an epidemic affected the community of the Nkana Copper Mine. During tills epidemic nine European and three African cases were reported. Three of the European cases-two children and one adult-died, a mortality rate of 33 per cent. It is considered probable that the infection was introduced into the community possibly by military personnel returning from the Middle East where the disease at the time was endemic.