Prevalence of tick-borne pathogens in migratory birds and their ticks in Lithuania

Abstract

Some studies suggests that the spread of tick-borne pathogens in new locations is related with ticks carried by birds. However, there are still lack of information about the bird’s infection with tick-borne pathogens and the influence of birds as a carrier of ticks and their pathogens. For this reason, the study to evaluate the presence of tick on migratory birds and their pathogens diversity in Lithuania were conducted. Ventės ragas ornithological station was selected as an important study area for North-West bird’s flyway route migration stop oversite.For tick species identification morphological and molecular methods were used. Collected ticks were screened for the presence of epidemiologically important pathogens such as Borrelia spp., Anaplasma phagocytophilum and Rickettsia spp. A total 5099 birds belonging to 42 bird species were caught and 1262 ticks from 22 bird species were collected. The highest infestation of ticks in Lithuania were found on blackbirds (Turdus merula), redwings (Turdus iliacus), song thrushes (Turdus philomelos), dunnocks (Prunella modularis) and European robins (Erithacus rubecula). The infestation rate of ticks was higher in short migrant birds(χ2 =19.537, df=1, p<0,001), which feeds on ground (χ2=711.58, df=2, p<0,001) and migrate during the night (χ2 =510.7, df=2, p<0,001).The dominant tick species on birds was Ixodes ricinus. Besides, exotic Hyalomma marginatum nymphs were identified. For the first time Rickettsia helvetica, Rickettsia monacensis, Rickettsia aeschlimanii and Borrelia valaisiana was detected in ticks from migratory birds in Lithuania.