Development and evaluation of Indirect Hemagglutination Antibody Test (IHAT) for serological diagnosis and screening of bovine cysticercosis in Ethiopia

Abstract

The study was conducted to develop and evaluate an Indirect Hemagglutination Antibody Test (IHAT) for the serological diagnosis of Cysticercus bovis in live animals. IHAT was set-up in-house and used to test serum samples of cattle against sheep red blood cell (SRBC) coated with crude extracts of C. bovis cyst. Serum samples for screening were collected from Addis Ababa abattoir (n=522), a dairy farm from the suburbs of Addis Ababa (n=101), and a traditional extensive farm (n=109). Postmortem inspection was conducted on a total of 522 animals slaughtered in Addis Ababa Abattoir, out of which 39 (7.5%) were positive for C. bovis.  Thirty-seven of these had viable C. bovis cysts. IHAT titres were determined from serially diluted sera, with a cut-off value set at a titre of 1:64. Cross reaction with other helminths was either absent or very low.  Sensitivity and specificity of the IHAT were 100% and at least 90%, respectively. Based on this test, 149 cattle (28.5%) from the Abattoir, 33 cattle (30.3%) from the extensive farm and 8 cattle (7.9%) from the dairy farm were positive for C. bovis. The difference in prevalence between the dairy farm and extensive farm was significant (P<0.05). Further refinement and improvement of the test is necessary to increase the diagnostic potential. The test is recommended for use in large scale serological screening and mapping of C. bovis infection in major animal husbandry locations in Ethiopia.