Abstract
Onchocerca volvulus microfilariae from 130 patients in 8 northern Guinea savanna villages of the Jos Plateau were stained by the naphthol AS-TR-phosphate method for the demonstration of acid phosphatase. Microfilariae were classified into 13 types according to their staining characteristics. Five corresponded to the enzyme types already reported by some workers on the West African rain-forest and Sudan savanna strains of O. volvulus. Eight types showed intense enzyme activity in the regions of the amphids and phasmids, in addition to any other structures in microfilaria.
Highly significant variations in type frequency (p<0.001) were observed between microfilariae from the summit area of the Jos Plateau and those from the villages in the northern area where the Guinea savanna shares common borders with the Sudan savanna.
The multiple enzyme patterns revealed in this study indicate that the O. volvulus microfilariae of the Jos Plateau are more polymorphic in relation to enzyme staining than the strains of the parasite from Yemen, Guatemala, Venezuela, and the West African rain-forest and Sudan savanna. A brief background of the study area is given and the significance of these findings is discussed.
