Ocular infection with an avian trematode (Philophthalmus sp)

Abstract

Adult trematodes of the genus Philophthalmus that parasitize the conjunctival sac of birds can cause accidental human infection. Human philophthalmosis is rare, but isolated cases have been reported from several countries including Sri Lanka. Adult flukes lay eggs that hatch on contact with water and develop in snail hosts. The emerging cercariae encyst on animate or inanimate objects in water infecting avian definitive hosts through ingestion, and then migrate to the eye. However, direct ocular infection can occur, and is the common route of infection in humans. We report the third case of philophthalmosis in Sri Lanka, and probably the first report of an indigenous infection.

Key words: Philophthalmus, human philophthalmosis, trematode zoonoses, ocular parasites, eye fluke  

DOI: 10.4038/cmj.v54i4.1454

Ceylon Medical Journal Vol.54(4) 2009: 128-129