Anoplocephala and Paranoplocephala
The tapeworms Anoplocephala perfoliata, A. magna and Paranoplocephala mamillana occur in horses around the world.
Summary
Taxonomy
Morphology
Host range and geographic distribution
Life cycle - indirect
Epidemiology
Because of the requirement for a free-living arthropod intermediate host, significant transmission of tapeworms among horses requires access to pasture, and in Canada most transmission is likely to occur during the summers.
Pathology and clinical signs
Diagnosis
Adult tapeworms may be seen in the feces, particularly in the fall, and typical eggs recovered by faecal flotation. The sensitivity for egg detection is, however, poor because egg output is often sporadic. A serological test that detects antibodies to an antigen specific for A. perfoliata has been developed, and is commercially available in the UK and the US, but not in Canada. This test is to some extent quantitative and provides an estimate of parasite burdens, but antibody levels can remain high in the absence of adult tapeworms from the intestinal lumen. A coproantigen test (not commercially available in Canada) has been shown to be more sensitive than simple flotation. Recent work in Canada has demonstrated that in some horses a faecal flotation done 24-48 hours following treatment with an anthelmintic effective against A. perfoliata (for example, praziquantel) significantly increases test sensitivity compared to a flotation prior to treatment.
Treatment and control
Public health significance
Neither Anoplocephala species nor P. mammillana are known to be zoonotic