Anaplasmosis in Uganda. II. Prevalence of bovine anaplasmosis

ABSTRACT

The prevalence of bovine anaplasmosis was studied in 320 Zebu cattle randomly selected from three regions of Uganda (central; south-western and north-western) using DOT-ELISA; Western immunoblotting; Rapid Card Agglutination Test (RCAT); Capillary Tube Agglutination Test (CAT); Complement Fixation Test (CFT); and parasitological techniques. Dried blood on Whatman filter paper no. 1 was eluated in PBS 0.05pc Tween 20 prior to testing at an initial dilution of 125. The incidence of parasitaemia ranged from 25pc in the central region to 35pc in the north-western region and the serological prevalence was lower in the central region and highest in the north-west. Prevalence rates assayed by DOT-ELISA and Western immunoblotting were 1.5-fold greater than those tested with RCAT and 3-fold greater than in CAT. The overall prevalence rates by DOT-ELISA and Western immunoblotting compared favourably with CFT data. The present data utilizing dried blood on filter papers indicate that there is a high prevalence of anaplasmosis in those regions of Uganda surveyed and it confirms our observations and those of others that collecting blood on filter papers is a suitable technique for large-scale screening and for seroepidemiological studies