A survey for Ilesha Bunyamwera group virus antibodies in sera from domestic animals and humans in three ecological zones of Nigeria.

343 persons, 58 children and 285 adults, from three ecological zones: rainforest, savannah, and plateau were tested for the presence of Ilesha virus N antibodies in their sera. Neutralization tests were conducted in suckling mice using the constant virus--constant serum technique. 155 subjects (45%) had Ilesha immunity: 22 children (38%) and 133 adults (44%). The highest percentage of positive sera was found in the savannah (54%), followed by the plateau and rainforest. A further analysis of the results shows that the virus is more active in rural communities than in urban centres. A total of 68 sera from domestic animals (cows, sheep, goats, and pigs) were tested. Antibodies were found only in cows and goats. The absence of antibodies in sheep and pigs may be due to the small number of sera tested.