Diagnosis of canine echinococcosis: comparison of coproantigen detection with necropsy in stray dogs and red foxes from northern Jordan.

The sandwich enzyme linked immunosorbent assay (ELISA) was used as a diagnostic test for Echinococcus granulosus infection by detecting coproantigens in 94 stray dogs Canis familiaris and eight red foxes (Vulpes vulpes) from northern Jordan. The results were analyzed in relation to actual helminth infection as revealed by necropsy. The infection rate of dogs with E. granulosus was 13.8% with a worm load ranging between 3-> 10,000 per infected dog. In contrast, eight of 13 E. granulosus infected dogs were coproantigen positive (overall sensitivity 61.5%). The sensitivity increased to 87.5% and 100% in dogs harboring > 20 and > 100 worms/dog, respectively. The specificity of coproantigen-ELISA was 91%. The greatest cross-reactivity was found in dogs infected with Dipylidium caninum. The positive and negative predictive values for the coproantigen-ELISA test were 50% and 94.2%, respectively. Thus, a coproantigen negative dog is most probably truly negative for E. granulosus. In contrast, a coproantigen positive dog may not be truly positive for E. granulosus, except if it has a high worm burden of > 100 worms/animal.

Prevalence of intestinal helminths of dogs and foxes from Jordan.

Necropsy of 340 stray and semi-stray dogs (Canis familiaris) and nine red foxes (Vulpes vulpes) from Jordan revealed that 239 dogs (70.3%) and all foxes were infected with at least one intestinal helminth species. No trematodes were found in the intestine of these hosts. The overall infection rates with cestodes, nematodes and acanthocephalans in dogs were 66.8%, 4.4% and 2.9%, respectively. The following cestodes were identified: Echinococcus granulosus (9.4%), Taenia pisiformis (11.8%), T. hydatigena (7.4%), T. ovis (4.4%), T. multiceps (3.8%), T. taeniaeformis (2.9%), Dipylidium caninum (19.4%), Joyeuxiella (3.2%), Diplopylidium (2.4%), and Mesocestoides (0.9%). Other intestinal worms in dogs were Toxascaris (2.6%), Toxocara canis (1.2%), and Protospirura (0.6%) nematodes, and gigantorhynchiid acanthocephalans (2.9%). Intestinal helminths found in foxes included cestodes (D. caninum, Joyeuxiella, Diplopylidium, Mesocestoides), nematodes (Protospirura, Uncinaria stenocephala and Oxynema) and an acanthocephalan (Macracanthorhynchus). In both hosts, most helminths were recovered from the second intestinal segment of four equally divided segments.