Thelaziosis due to Thelazia callipaeda in Europe in the 21st century—A review

Ophthalmic Thelazia callipaeda infections: first feline and new canine imported cases in Germany

“…Ocular thelaziosis is spreading in Europe (do Vale et al 2019 ; Marino et al 2020 ), and the number of reports on T . callipaeda infections has increased throughout the continent (do Vale et al 2019 ), not only in domestic and wild animals but also in humans (e.g. Dolff et al 2020 ).…”

“…The male fruit fly P. variegata is the obligate intermediate host of T. callipaeda , and it is considered as endemic in Europe, including the north of the Alps. Establishment of this particular intermediate host in new geographic areas occurs especially in regions with decaying fruits and fruit plantations, such as strawberry fields and orchards comprising apple and plum trees (Magnis et al 2010 ; do Vale et al 2019 ) contributing to an increase of ocular thelaziosis episodes. Interestingly, in contrast to a high degree of genetic variability among isolates from Asia (Otranto et al 2005b ), no genetic variation was recorded between individual nematodes collected from different host species (i.e.…”

“…In Europe, eye worms have been reported in cattle ( T. rhodesii , T. skrjabini , T. gulosa ), horses ( T. lacrymalis ) and carnivores ( T. callipaeda ), such as dogs, cats, foxes and wolves. Recently, various reports brought to light T. callipaeda infections of dogs but also of cats, rabbits and humans, mainly from poor socio-economic settings in different Asian countries (Otranto and Traversa 2005 ; do Vale et al 2019 ) but also in several European regions. Consequently, this vector-borne helminthiasis is currently considered as an emergent disease (Colella et al 2016a , 2020 ).…”

Suspected autochthonous Thelazia callipaeda infection in a dog in northern Germany

“…Since its first detection in Italy in the 1980s, T. callipaeda has spread across Europe, with recent cases of autochthonous thelaziosis in carnivores from Bulgaria (Colella et al 2016), Slovakia (Cabanova et al 2017), Hungary (Farkas et al 2018), Moldova (Dumitrache et al 2019) and Austria (Hodzic et al 2019), as well as several reported human cases (Paradzik et al 2016;Tasic-Otasevic et al 2016;Dolff et al 2020). Important factors in the expansion of canine thelaziosis include the travelling of infected dogs to/from endemic regions and the presence of a sylvatic cycle mainly maintained by foxes (Otranto et al 2009;do Vale et al 2019).…”

“…The parasite was first described from Asia in 1910 (Railliet and Henry 1910), where it is widespread. The first case of canine thelaziosis in Europe was described in Italy in the late 1980s (Rossi and Bertaglia 1989), and the distribution of this 'oriental eye worm' has since extended to larger parts of Europe, with enzootic areas in southern Europe (do Vale et al 2019).…”