Penetration ofTrichobilharziacercariae into mammals: dangerous or negligible event?

Abstract

Summary :Bird schistosomes and cases of human cercarial dermatitis occur worldwide, but the number of cases is not monitored. Experiments with two schistosomes, namely Trichobilharzia szidati and T. regenti, show that they possess potent tools to penetration bird and mammalian skin, as well as exhibit species-specific migration patterns within vertebrate bodies. Therefore, the infections may affect different organs/tissues e.g. lungs or spinal cord. In this minireview, the adaptations and pathogenic effects of bird schistosomes in experimental mammals are discussed, and some ideas/hypotheses on risks to humans from exposure to bird schistosome cercariae are expressed.

Prevalence of schistosome induced cercarial dermatitis in north of Iran

“…A total of 427 people of this group were studied and 38 of them (1.6% of the total population) were infected which constituted 27.3% of the whole infected population, 338 people were studied in the age group of [10][11][12][13][14][15][16][17][18][19] years old and only 8 of them (0.3% of the total population) were infected. No cases of infections were reported for 2 age groups of 60-69 and more than 70 years old (Table 2).…”

“…This disease is a kind of Zoonosis diseases and is reported in the north ( Mazandaran and Gilan province) and south( Khuzestan province) of the country [6,7] . Cecarial dermatitis, is regarded a new disease in Europe [8,9] . the aim of the study was to determine the prevalence of cecarial dermatitis among the over 10-year old of the rural areas of Mazandaran province.…”

Egy ritka zoonosis: a Schistosoma turkestanicum vérmétely által okozott cercaria dermatitis Magyarországon

“…Ugyanennek a genusnak néhány faja csak állatban képes kifejődni, de ha azok lárvája az ember bőrének közelébe jut, képes befurakodni abba, noha ott mindenképpen elpusztul. A madarak vérmételyeinek több fajáról is bebizonyították, hogy a vízben úszó farkos lárvájuk, az úgynevezett cercaria ez utóbbi módon viselkedik [8], ezért kijelenthetjük, hogy a melegvérű gerinceseket fertőző vérmételyek lár-vái alkalmanként képesek lehetnek az ember bőrébe jutni.…”

“…A rizsföldeken dolgozók gyakran szenvednek ilyen bőrgyulladástól [21,22], míg a nyugati világ országaiban a tópartok nyaralóvendégei leginkább a "swimmers' itch" néven ismerik e furcsa fertőzést [19]. Leggyakrabban a vízi madarak vérmételyeinek cercariái okozzák a bántalmat, de okozhatja emlősállat vér-mételye is [8,11].…”

Cathepsins B1 and B2 in the neuropathogenic schistosome Trichobilharzia regenti: distinct gene expression profiles and presumptive roles throughout the life cycle

“…Repeated infections result in an inflammatory reaction of the skin called cercarial dermatitis. Due to the increasing number of outbreaks all around the world, cercarial dermatitis has been considered as reemerging disease (Kolářová 2007;Horák et al 2008). Among schistosomes, Trichobilharzia regenti is the only species described so far having a unique migration route within vertebrate hosts: After penetration of the skin, the invasive larvae enter peripheral nerves and continue via the spinal cord and brain to the nasal cavity of birds, causing neuromotor disorders or paralyses of birds and even experimental mammals (Hrádková and Horák 2002).…”