Comparison of synthetic tyvelose antigen with excretory-secretory antigen for the detection of trichinellosis in swine using enzyme-linked immunosorbent assay.
Two enzyme-linked immunosorbent assay (ELISA) systems, one using natural excretory-secretory (ES) antigens and the other a synthetic glycan antigen (3,6-dideoxy-D-arabinohexose [tyvelose, TY]), were evaluated for the serological diagnosis of trichinellosis in swine. Sensitivity was estimated using samples (n = 113) collected 3-21 wk PI from 15 experimentally infected pigs, and specificity was estimated using samples (n = 397) from a population of Trichinella spp.-free pigs. Results were analyzed using 2 cutoff values recommended in international guidelines (Office Internationale des Epizooties [OIE]) and by the optimal cutoff level as determined by receiver-operator characteristic (ROC) analysis. The ROC-optimized TY-ELISA consistently performed better than all other combinations. None of the combinations of test and cut-off detected infected pigs sooner than 35 days; however, the ROC-optimized TY-ELISA identified 8 of 15 pigs earlier than the ES-ELISA and detected 2 pigs missed by all other tests. At 49 days PI the sensitivity and specificity of the ROC-optimized TY-ELISA were 94.3 and 96.7%, respectively, as compared with the ROC-optimized ES-ELISA at 84.9 and 96.0%, respectively. The ROC-optimized TY-ELISA was 100% specific at OIE-recommended cut-offs. This study indicates that the TY-ELISA is as good or better than the ES-ELISA for the detection of trichinellosis in swine.
Forbes
Lorry B
LB
Centre for Animal Parasitology, Saskatoon Laboratory, Canadian Food Inspection Agency, 116 Veterinary Road, Saskatoon, Saskatchewan, Canada S7N 2R3. lforbes@inspection.gc.ca
Appleyard
Greg D
GD
Gajadhar
Alvin A
AA
D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood; D000947:Antigens, Helminth / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000662:veterinary*; D005260:Female; D006601:Hexoses / Q000138:chemical synthesis / Q000276:immunology; D012372:ROC Curve; D012680:Sensitivity and Specificity; D013552:Swine; D013553:Swine Diseases / Q000175:diagnosis* / Q000276:immunology; D014234:Trichinella / Q000276:immunology; D014235:Trichinellosis / Q000175:diagnosis / Q000276:immunology / Q000662:veterinary*
D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D006601:Hexoses; C009616:tyvelose