Evaluation of an enzyme-linked immunosorbent assay (ELISA) for the serological diagnosis of sarcoptic mange in swine.

An enzyme-linked immunosorbent assay (ELISA) using an extract from Sarcoptes scabiei var. culpes as antigen was evaluated for its usefulness in monitoring antibodies to S. scabiei var. suis in naturally infected pigs. Five hundred and fifty-eight serum samples from certified Sarcoptes-free pigs (120 from weaned piglets, 218 from fatteners and 220 from adult sows) and 94 samples from certified Sarcoptes-infected pigs (35 from weaned piglets, 45 from fatteners and 14 from adult sows) were examined. The cut-off optical density (OD) values, considered to reflect the presence of antibodies to S. scabiei var. suis, were determined to be 0.059, 0.213 and 0.374 for weaners, fatteners and sows, respectively. The specificity of the ELISA was high (> or = 98%) for all age groups. Sensitivity was highest in the piglets (80%), followed by fatteners (78%) and sows (50%). These results indicate that an ELISA may be a simple and valuable alternative to monitor S. seabiei var. suis infections in naturally infected weaners and fatteners.