Evaluation of a five-antigen ELISA for diagnosis of tuberculosis in cattle and Cervidae.
OBJECTIVE
To determine the validity of a 5-antigen ELISA for detection of tuberculosis in cattle and Cervidae.


METHODS
Cross-sectional observational study.


METHODS
Serum samples collected from 5,304 cattle in 23 herds and 1,441 Cervidae in 12 herds.


METHODS
Discriminant analysis was used to determine the linear combination of antigens that accurately predicted the true Mycobacterium bovis infection status of the most animals. The resulting classification functions then were used to calculate the percentage of animals that were correctly classified (ie, sensitivity and specificity). The kappa statistic was calculated to evaluate different combinations of test results.


RESULTS
Of the 23 cattle herds, 4 dairy and 2 beef herds were considered infected. Of the 12 Cervidae herds, 5 were considered infected. For cattle, the specificity and sensitivity of ELISA, using the discriminant function, were 56.4 and 65.6%, respectively. For Cervidae, the specificity and sensitivity of ELISA, using the discriminant function, were 78.6 and 70.0%, respectively.


CONCLUSIONS
Results suggest that the 5-antigen ELISA would not be a good test for tuberculosis, especially in cattle, if used alone. However, when results of the ELISA and tuberculin test were interpreted in parallel, sensitivity of the combination was greater than sensitivity of either test alone. Similarly, when results of the 2 tests were interpreted in series, specificity of the combination was greater than specificity of either test alone.
Gaborick
C M
CM
Center of Veterinary Epidemiology and Animal Disease Surveillance Systems, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins 80523-1676, USA.
Salman
M D
MD
Ellis
R P
RP
Triantis
J
J
D000818:Animals; D000942:Antigens, Bacterial / Q000097:blood*; D002417:Cattle; D002418:Cattle Diseases / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology; D003430:Cross-Sectional Studies; D003670:Deer; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000592:standards / Q000662:veterinary*; D005260:Female; D008297:Male; D009163:Mycobacterium bovis / Q000276:immunology; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014374:Tuberculin Test / Q000379:methods / Q000592:standards / Q000662:veterinary*; D014380:Tuberculosis, Bovine / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology; D014481:United States / Q000453:epidemiology
D000942:Antigens, Bacterial