Updates on the distribution and host spectrum of Dirofilaria repens in the Republic of Uzbekistan

Among the zoonotic mosquito-borne nematodes, Dirofilaria repens and Dirofilaria immitis (Spirurida, Onchocercidae) are highly significant from a public health perspective. While D. immitis is also of major veterinary concern, D. repens is regarded as less pathogenic for carnivores, but is the main causative agent of human dirofilariosis throughout the Old World. In the Republic of Uzbekistan, recent data refer exclusively to D. immitis infection in domestic and wild carnivores, while the current prevalence and distribution of D. repens remain unknown. Between 2015 and 2021, a total of 559 domestic and wild carnivore carcasses were collected and examined by necropsy. All subcutaneous nematodes were collected and identified morphologically. The overall prevalence of D. repens infection was of 11.03% in domestic dogs, Canis familiaris , and 9.29% in wildlife hosts: golden jackals, Canis aureus (11.76%), wolves, Canis lupus (9.09%), red foxes, Vulpes vulpes (9.23%), and jungle cats, Felis chaus (7.14%). Additionally, a human case of subcutaneous D. repens infection was also documented. The present study represents the first recent assessment of the occurrence of the zoonotic filarioid D. repens in the Republic of Uzbekistan. It indicates a wide distribution in domestic dogs and four species of wildlife hosts throughout the country, raising awareness on the public health risks associated with this parasite.