Genital myiasis of a sheep by Wohlfahrtia magnifica , in Ghamsar , Kashan , Iran

Flies from Calliphoridea, Sarcophagidae and Cuterebridea families cause most of the myiasis. Myiasis caused by them is divided into obligatory, optional and accidental type3,4. In obligatory myiasis, it is essential for fly larvae to live on a living host. In the optional myiasis, larvaes invaded animal corpse, but in especial condition they can infest live host, which is called accidental myiasis. GI myiasis in human is an example of accidental myiasis. Cutaneous myiasis besides harming skin of domestic animals, reduce economical value of their leather. Wohlfahrtia flies belong to Sarcophagidae family, and induce obligatory myiasis. The mature fly length 8 to 14 millimeter; have gray color with black circle spots on their abdomen. Wohlfahrtia fly has worldwide distribution2, it is reported from Mediterranean, South and East Europe, North Africa, and China5. Sheep is its main host. Cat and dog were reported as the important reservoirs in the epidemiology of wohlfahrtiosis in Hungary6. Recently human myiasis by wohlfahrtiosis has been reported from Europe and Asia7-11. Genital myiasis caused by wohlfahrtiosis


Introduction
Myiasis described as any harm caused by dipterous especially fly in organs or tissues of vertebrate animals (live or dead tissues).Fly larvaes feed from living or dead tissues of animal, which cause serious harm to animal.Based on infested organ of human or animal the infestation call coetaneous myiasis, orbital myiasis, nasopharynx myiasis, and so on 1,2 .
Flies from Calliphoridea, Sarcophagidae and Cuterebridea families cause most of the myiasis.Myiasis caused by them is divided into obligatory, optional and accidental type 3,4 .In obligatory myiasis, it is essential for fly larvae to live on a living host.In the optional myiasis, larvaes invaded animal corpse, but in especial condition they can infest live host, which is called accidental myiasis.GI myiasis in human is an example of accidental myiasis.Cutaneous myiasis besides harming skin of domestic animals, reduce economical value of their leather.
Wohlfahrtia flies belong to Sarcophagidae family, and induce obligatory myiasis.The mature fly length 8 to 14 millimeter; have gray color with black circle spots on their abdomen.Wohlfahrtia fly has worldwide distribution 2 , it is reported from Mediterranean, South and East Europe, North Africa, and China 5 .Sheep is its main host.Cat and dog were reported as the important reservoirs in the epidemiology of wohlfahrtiosis in Hungary 6 .Recently human myiasis by wohlfahrtiosis has been reported from Europe and Asia 7-11 .Genital myiasis caused by wohlfahrtiosis was also reported from Sicily, Italy 12 .In Iran like other countries beside domestic animal infestation, myiasis has been also reported in human.In Khozestan province, Behbahan area myiasis were observed in sheep, cow, goat, horse, dog and donkey 9 .Researchers have also reported wohlfahrtiosis infestation among wild animals 10 .In Iran, human myiasis has been reported sporadically.Wohlfahrtia magnifica, which cause obligatory myiasis, induce cutaneous myiasis, myiasis in ear, nose and eye of livestock and human.Therefore reporting any, contamination by Wohlfahrtia magnifica has its especial value.This is a case report of wohlfahrtiosis inducing genital myiasis in sheep, its diagnosis, and treatment.

Case Report
In August 2010 during examination of a herd of 150 goats and sheep, in Ghazaan area, a myiasis infestation in genital organ of a sheep was detected.This area is located in north east of Isfahan province and in south of Kashan town.The sheep was a 4-year old ewe with severe infection in vulvar and perineal area.Wound, edema and larvaes activity was obvious.After examination, larvaes were collected alive in a container.The wound was washed with betadine; necrotic tissues, discharge, and pus were removed; and after disinfection wound was treated with topical antibiotics.The larvaes were transported to the laboratory of Environmental Health Group of Kashan Medical Sciences University.The larvaes were kept in special containers, and were fed to reach their maturity.The larvaes were diagnosed with stereomicroscope and taxonomic keys by/of Zumpt (1965).To diagnose the genus and species of fly, baby flies were dissected under stereomicroscope, anterior and posterior respiratory holes and head-pharyngeal skeleton were separated from body.Each of separated parts was placed on the slides/lam and was examined under light microscope.The larvaes were cultured on an environment with meat, and developed to pupa.Using diagnosis keys, morphologic characteristics of larvaes, and pupa opening process, the cause of wound diagnosed as Wohlfahrtia magnifica.The collected pupas that were kept in normal laboratory temperature grow to adult fly, which with morphologic assessment diagnosed as Wohlfahrtia magnific.Having a wound is essential for cutaneous myiasis in animals.Superficial injuries or deep wounds in animals are main factors, which attract fly.Skin ruptures caused by hitting, scratches from sharp objects, place of carnivorous animals bite, and any skin injury attracts flies that cause myiasis.Furthermore, wound discharge or any injury cause fermentation and decompose of skin superficial proteins by available microorganism, induce skin decay and produce a non-pleasant smell that attracts flies.Flies that cause dermal myiasis are active in area with relatively warm and moist climate 3,4,24 .Kashan is a warm and dry part of country, which located in mountain area and provide suitable environment for myiasis induction in human or livestock.In tropical regions, flies are active throughout the year.

Conclusion
Since flies are attracted to the wounds and injury areas because of smell induced by microorganisms activity, regular examination of farm animals during grazing, will reduce the number and extent of injuries caused by flies.Examining restless and upset animals during grazing will help to recognize infested livestock.The risk of myiasis as a common zoonotic disease in tropical and subtropical climates is high; therefore, it is essential to educate people who are involved with domestic animals.