First findings and prevalence of adult heartworms (Dirofilaria immitis) in wild carnivores from Serbia

Heartworm (Dirofilaria immitis) is a parasitic roundworm that causes a zoonotic disease known as dirofilariosis. Little is known about the role of wild carnivores serving as reservoirs in nature. Therefore, we examined 738 hearts and lungs of free ranging wild carnivores from Serbia to determine the presence of adult heartworms. During the period 2009-2013, the prevalence in golden jackals (Canis aureus) was 7.32 %, in red foxes (Vulpes vulpes) 1.55 %, in wolves (Canis lupus) 1.43 %, and in wild cats (Felis silvestris) 7.69 %. No adult heartworm specimens were found in beech martens (Martes foina), stone martens (Martes martes), European polecats (Mustela putorius), badgers (Meles meles) or otter (Lutra lutra). The highest recorded prevalence was in 2013 (7.30 %) and the lowest in 2012 (1.6 %). In jackals, the prevalence was higher in males (10 %) than in females (4.06 %), while in foxes the prevalence was 1.75 % in males and 1.26 % in females. The most infected host was a wolf in which 37 adult specimens were found. Because of the potentially significant role in the life cycle of D. immitis, populations of wild carnivores in Europe should be further examined and tested for heartworm infections.