Studies on serodiagnosis of glanders using various antigens
Abstract
Glanders is an important reemerging zoonotic disease in India. Since there is no proper treatment or vaccine available for glanders, its timely diagnosis, prevention and control are utmost important. In view to have a quick and effective diagnostic tool, the present study on serodiagnosis of glanders was planned. The standardization of Indirect Haemagglutination (IHA) test and Dot Enzyme-linked immunosorbent assay (Dot ELISA) were performed with Complement Fixation Test (CFT) antigen, mallein PPD and recombinant antigen for the diagnosis of glanders and applied on 248 field equine sera collected from various States of the country. A significant IHA titre of 320 and above was found as positive diagnostic titre for glanders. The tanned formalinised SRBCs were found better when used on the same day of coating antigens. The albumin bovine serum- phosphate buffered saline (ABS-PBS) was found better diluent than normal rabbit serum-phosphate buffered saline (NRS-PBS). Analysis of diagnostic test characteristics for the comparative efficacy of IHA test and Dot ELISA with various antigens was done. The specificity of IHA test with all the three antigens ranged from 99.16% to 99.47%, but the sensitivity of IHA was found maximum (63.64%) with CFT antigen. The accuracy of prediction of the IHA test with all the three antigens was ranged from 95.56% to 97.58%. The specificity of Dot ELISA with all three antigens was found to be 97.47% and the sensitivity was 100% with CFT and recombinant antigens and 90.91% with mallein PPD. The accuracy of prediction of Dot ELISA varied from 97.18% to 97.58% with the various antigens. The present study revealed that the Dot ELISA with recombinant antigen can be used for field screening of equine sera for the diagnosis of glanders.