ELISA FOR BOVINE SCHISTOSOMIASIS VACCINE EVALUATION: A PRELIMINARY REPORT

Abstract

Six calves were immunized with schistosomula of Schistosoma bovis irradiated at 3 or 20 Kilorad (Krad) and three calves were kept as controls. Twenty four weeks post immunization, three calves (one from the 20 Krad and two from the 3 Krad group) were challenged with normal cercaria of S. bovis. The immune response was monitored by agar gel immunodiffusion (AGID) and the Enzyme Linked Immunosorbent Assay (ELISA) using adult worm antigen. Using AGID, precipitin lines were observed only with sera from challenged animals. Using ELISA, the immune response of the vaccinated calves was first detected by 2-3 weeks, peaking by 6-8 weeks post vaccination. The immune response of the three challenged calves was elevated by 2 weeks post challenge, peaking at 8-10 weeks post challenge and remained high throughout the experimental period. This study suggests that ELISA could be used for diagnosis of bovine schistosomiasis.