Episthmium caninum (Verma, 1935) Chatterji, 1954
ETYMOLOGY:Epi (dorsal) + isthmium (constriction) [for the break in the spines around the mouth] and caninum for the canine host
SYNONYMS:Episthochasmus caninum Verma, 1935; Echinochasmus corvus (Bhalerao, 1926) Gupte and Pande, 1963. Some consider Episthmium a subgenus of Echinochasmus; Gupta and Pande (1963) thought this parasite to be synonymous with the species occurring in the crow.
HISTORY: This worm was originally described from dogs in Calcutta (Verma, 1935). This fluke has also been rarely reported from the cat (Pande, 1973).
GEOGRAPHIC DISTRIBUTION: A rare parasite of cats reported form Lucknow India (Pande, 1973).
LOCATION IN HOST: Small intestine.
PARASITE IDENTIFICATION: This worm is elongate, measuring 1 to 2 mm in length. The genus Episthmium differs from Echinochasmus in that the vitelline follicles extend anterior to the ventral sucker.
The eggs are 80 to 85 µm long by 63 to 66 µm wide.
LIFE CYCLE: Not definitely known, probably utilizes fish much in the same manner as Echinochasmus perfoliatus.
CLINICAL PRESENTATION AND PATHOGENESIS: Thought to be asymptomatic.
TREATMENT: Probably praziquantel, but not reported.
EPIZOOTIOLOGY: Cats probably become infected by eating raw fish; it may be that the normal host is a bird such as the crow (Gupta and Pande, 1963).
HAZARD TO OTHER ANIMALS: None. Although other hosts are infected, the major means of infection is through the ingestion of the fish intermediate host which requires that the appropriate snail also be available. Thus, infection of these other hosts will typically only occur in the wild.
HAZARD TO HUMANS: None known.
CONTROL/PREVENTION: Probably prevention of the ingestion of raw fish.
REFERENCES:
Gupta VP, Pande BP. 1963. On a trematode of the genus Echinochasmus Dietz, 1909, with remarks on the species occurring in Indian carnivores. Parasitology 53:169-175.
Pande KC. 1973. Studies on some known and unknown trematode parasites. Ind J Zootomy 14:197-219.
Verma SC. 1935. Studies on the Indian species of the genus Echinochasmus. Part I. and on an allied new genus Episthochasmus. Proc Ind Acad sci 1:837-856.