First autochthonous Dirofilaria immitis (Leidy, 1856) infection in a dog in Hungary

A 4 year-old, male Hungarian Vizsla dog which had never been abroad was referred with poor general condition, decrease in body weight, haematemesis and jaundice to the Central Clinic of Veterinary Science University, Budapest. After symptomatic treatment abdominal ultrasonography and diagnostic laparatomy were carried out. The dog was humanely euthanized two days later following owner’s consent because of sudden worsening of clinical conditions. Two adult heartworms (Dirofilaria immitis) were found in the right ventricle partially coiling around the tricuspid valve. PCR on blood was positive for both D. immitis and Dirofilaria repens while only D. repens microfilariae were found by modified Knott’s test and the serological test was negative for D. immitis antigens. This is the first, confirmed report of autochthonous canine heartworm infection in Hungary.