Tick-host-pathogen dynamics among passerine birds in northwestern Pennsylvania

Bird-facilitated transport of ticks has been documented to promote the spread of tick species and the invasion of tick-borne diseases. However, in Western Pennsylvania, there has been limited research examining the relationship between passerine birds as potential hosts of ticks and the pathogens they may carry. To address this gap, we conducted a study to investigate the tick-host-pathogen interactions and the risks they might pose on avian and human communities. Questing ticks were collected through cloth-dragging in three counties in Northwestern Pennsylvania and identified by life stage and species. Passerine birds were mist netted at the same locations, attached ticks were removed, were identified morphologically, sorted by life stage and species, and tested for Borrelia burgdorferi, Borrelia miyamotoi, Anaplasma phagocytophilum, and Babesia microti. A total of 187 unique passerine birds consisting of 18 different species were sampled, from which 684 larval and 151 nymphal ticks were collected. Only partially or fully engorged larval ticks were screened for pathogens, all nymphs were screened. By identifying the bird and tick species responsible for the transmission of these pathogens, we gained better insight on how different bird species serve as hosts and distribute ticks and pathogens to new locations. Additionally, public health officials in Northwestern Pennsylvania can implement strategies for early detection and prevention in local communities.