Bartonella infections in laelapid mites from small rodents in Lithuania

Abstract

The genus Bartonella contains facultative Gram-negative intracellular bacteria from the family Bartonellaceae which can cause bacteremia in humans and in a wide variety of animals. Hematophagous arthropods such as ticks and fleas parasitizing small rodents are considered potential vectors for various Bartonella species. However, the role of other ectoparasites - laelapid mites (Mesostigmata: Laelapidae) in transmission of Bartonella among rodent hosts needs to be confirmed. The aim of this study was to investigate the prevalence and diversity of Bartonella infections in laelapid mites parasitizing small rodents in Lithuania. A total of 670 small rodents of seven species (Apodemus flavicollis, A. agrarius, Myodesglareolus, Micromysminutus, Microtus oeconomus, M. arvalis and M. agrestis) were trapped during 2015-2016. Laelapidmites (n= 271) representing five different species (Laelapsagilis, Haemogamasus nidi, Eulaelapsstabularis, Myonyssus gigas and Hyperlaelaps microti) were collected from rodents. Bacteria DNA in mites was detected using a real-time PCR targeting a124 bp fragment of ssrA gene. All Bartonella-positive samples were analysed further by nested PCR and sequence analysis of 16S-23S rRNA ITS region. The overall prevalence of Bartonella spp. in mites was 14.4% (39/271). Bartonella infection was detected in three mite species L. agilis, H. nidi and M. gigas. Sequence analysis of 16S-23S rRNA ITS region revealed the presence of B. tayloriiin L. agilis, H. nidi and M. gigas mites, while Bartonella grahamii – only in L. agilis. Our results suggest a possible role for laelapid mites in the transmission of Bartonella spp. among rodents.