Screening of dogs for Echinococcus granulosus coproantigen in a low endemic situation in Cyprus

Abstract

In the framework of an echinococcosis surveillance and control programme in Cyprus, a commercial enzyme-linked immunosorbent assay (ELISA) (CHEKIT ® ECHINOTEST) designed for the detection of Echinococcus granulosus and E. multilocularis coproantigens was used in 1997–2000 for the investigation of large numbers of dogs. Most of the animals originated from areas where approximately 0.2% of the dogs had been found to be infected with E. granulosus in previous (1993–1996) arecoline surveys. The sensitivity of the coproantigen test was 83%, as determined in 35 dogs naturally infected with this cestode species. The specificity was 98% in 97 randomly selected dogs from Cyprus, but it was reduced to 80% in a group of 50 dogs, infected with Taenia spp. A total of 6551 dogs (mainly of rural origin) was examined, including three large groups ( N: 2928, 1761 and 1800) from the Government Control Area (GCA) in southern Cyprus and a small group ( N: 62) from the Non-Government Control Area (NonGCA) in the northern part of the island. Among the dogs from the GCA, 184 (2.8%) tested positive for coproantigen; coproantigen prevalences were 2.6, 4.9 and 1.1% in these three groups, and of 62 dogs from the NonGCA 8.1% were positive. The calculated true prevalences of E. granulosus in the dog population of the GCA ranged between 0.0 and 3.58%. The predictive values of the test, based on a 0.2% prevalence, was >99.9% for negative results, but very low (7%) for coproantigen-positive results. However, the relatively small number of coproantigen-positive dogs can be treated with praziquantel or the results can further be confirmed by arecoline purging.