Molecular investigation of tick-borne pathogens in ticks collected on migratory birds in Lithuania

Abstract

Wild birds are increasingly considered to be important in the global dispersal of tickborne pathogens as they are capable of transporting infected ticks over large distances. To define the role of migrating birds as hosts and disseminators of infected ticks in Lithuania we analysed immature stage of ticks feeding on different passerine bird species. During autumn 2009 and 2010 we screened 3 959 migrating birds at Ventės Ragas ornithological station and found 7.2% birds infested with ticks. The most infested bird species were Erithacus rubecula and Prunela modularis. We used PCR and sequence analyses for detection and identifying of pathogens in ticks collected from migrating birds. Forty eight tick pools (consisting of 487 Ixodes ricinus ticks) were screened for tick-borne pathogens. Borrelia spp. were detected in 9 tick pools, Babesia spp. in 6 tick pools and Anaplasma phagocytophilum in one tick pool. Three Borrelia species were identified: B.garinii, B.afzelii and B.miyamotoi. The results of the present study showed the pathway of introduction of B.miyamotoi in Lithuania and confirmed the impact of birds on spreading of non-native invasive pathogens in new areas. The present study is the first report of Babesia microti in Lithuania. We did not find tick-borne encephalitis virus (TBEV) in ticks collected from migrating birds. The bird species that carried the highest number of infected ticks were Parus major and Erithacus rubecula.