Diversity and Multiple Infections of Bartonella in Red Deer and Deer Keds

Bartonellae are zoonotic pathogens with a broad range of reservoir hosts and vectors. To examine sylvatic <i>Bartonella</i> reservoirs, tissue samples of red deer (<i>Cervus elaphus</i>, <i>n</i> = 114) and their associated deer keds (<i>Lipoptena cervi</i>, <i>n</i> = 50; <i>L. fortisetosa</i>, <i>n</i> = 272) collected in the Czech Republic were tested for the presence of <i>Bartonella</i> using PCR at four loci (<i>gltA</i>, <i>rpoB</i>, <i>nuoG</i>, ITS); PCR sensitivity was increased significantly by using primers modified for the detection of wildlife-associated bartonellae. One-third of the deer and 70% of the deer keds were <i>Bartonella</i> positive; within the tested animal tissues, usually the spleen was positive. The most prevalent <i>Bartonella</i> represents an undescribed species related to isolates from Japanese sika deer and <i>L. fortisetosa</i>. Additionally, <i>B. schoenbuchensis</i> sensu lato and <i>B. bovis</i> were found, together making up 17 genotypes characterized by multi-locus sequence typing, all unique compared to previously published sequences. Nanopore sequencing of selected samples revealed an additional 14 unique <i>Bartonella</i> genotypes, with up to six genotypes co-infecting one deer, highlighting the diversity of ruminant <i>Bartonella</i>. The high COI variety of examined <i>L</i>. <i>cervi</i> and <i>L</i>. <i>fortisetosa</i> suggests <i>L</i>. <i>fortisetosa</i> in central Europe is not a homogenous invasive population.