Abstract
The distribution of antibody to Nairobi sheep disease in sheep and goats in Kenya was found to coincide closely with that of the tick, Rhipicephalus appendiculatus. The proportions of a population in an enzootic area with antibody was similar in the different age groups. No antibody to the virus was found in rodent sera and while some low titres were found in some wild ruminant sera, these were considered to be most likely cross reactions with antibody to related viruses.