Dirofilariasis - the new zoonosis in Lithuania

Dirofilariasis is a group of zoonotic parasitoses caused by species of the genus Dirofilaria and transmitted by mosquitoes. Dirofilaria infections in Europe caused by D. immitis and D.repens. Parasites can infect wild and domestic canines, felines, and humans. Dogs are the main reservoirs. Climatic changes and an increase in the movement of reservoirs have an impact on the spread of dirofilariasis into previously non-endemic areas. In Lithuania, six human cases of D. repens infection were recorded during 2011-2014. However, the data on this zoonotic infection in Lithuania are still scare. Blood samples of 2180 randomly selected dogs presented in small animal clinic during 2014-2015 were investigated for filarial parasites. The species of the microfilariae were determined on the basis of their morphometrical characteristics and the Diffquick staining technique applied to blood smears and using Modified Knott’s test. Microfilariae were detected in blood smears of thirty-four (1.6%) dogs. For differentiation and accurate identification of the filarial species we also used PCR and pan-filarial primers (DIDR-F1, DIDR-R1) that amplify fragments of different length of the internal transcribed spacer region 2 (ITS2) of the ribosomal DNA from six different filarial species. Sequence analysis confirmed D. repens in all of investigated samples. In order to investigate wild Canidae as possible reservoirs for zoonotic filariae, foxes (Vulpes vulpes) and raccoon dogs (Nyctereutes procyonoides) killed on roads or during the hunting seasons 2014–2015 were examined. Splenic blood smears and blood coagula were used for detection of microfilaria in morphological and molecular diagnostics, respectivelyBiologijos katedraGamtos mokslų fakultetasLietuvos sveikatos mokslų universitetasVytauto Didžiojo universiteta