First autochtonous infection of a dog with Oslerus (Filaroides) osleri in the Czech Republic.

This case report describes an infection with O. osleri in a 10-month-old intact female Miniature German Spitz that presented with a 3-month history of progressive cough. Diagnosis was based upon visualization of characteristic lesions during bronchoscopy. Female parasites and first-stage larvae collected from tracheal nodules were morphologically identical to the larvae of O. osleri. First-stage larvae isolated from faeces were used for morphological and molecular confirmation of the diagnosis. Anthelmintic therapy with fenbendazole (50 mg/kg orally once daily for 2 weeks) was successful. This is the first report of autochthonous infection of a dog with O. osleri in the Czech Republic. Oslerosis should be considered in the differential diagnosis in young dogs with persistent respiratory signs.