Abstract
The family Hippoboscidae is a less known group of blood-sucking flies. Deer ked are particularly important for animal health; they may act as potential vectors of disease to ungulates, and may transmit pathogens to animals and humans. The aim of this study was to investigate the presence of Trypanosoma (Megatrypanum) DNA in deer keds using molecular methods. Results prove the presence of Megatrypanum trypanosome DNA in the studied winged adult deer keds and this is the first detection of this pathogen in Lipoptena fortisetosa. In addition, this paper evidences the occurrence of L. fortisetosa in two new locations: one in the Białowieża Primeval Forest, and another in the Strzałowo Forest Inspectorate (Piska Forest), both in north-eastern Poland.