Molecular detection of Bartonella spp. in deer ked (Lipoptena cervi) in Poland

Abstract

Background: The bacteria of the genus Bartonella are obligate parasites of vertebrates. Their distribution range covers almost the entire world from America, Europe, Asia to Africa and Australia. Some species of Bartonella are pathogenic for humans. Their main vectors are blood-sucking arthropods such as fleas, ticks and blood-feeding flies. One such dipteran able to transfer vector-borne pathogens is the deer ked (Lipoptena cervi) of the family Hippoboscidae. This species acts as a transmitter of Bartonella spp. in cervid hosts in Europe.

Methods: In the present study, 217 specimens of deer ked (Lipoptena cervi) were collected from 26 red deer (Cervus elaphus) hunted in January 2014. A short fragment (333 bp) of the rpoB gene was used as a marker to identify Bartonella spp. in deer ked tissue by PCR test. A longer fragment (850 bp) of the rpoB gene was amplified from 21 of the positive samples, sequenced and used for phylogenetic analysis.

Results: The overall prevalence of Lipoptena cervi infection with Bartonella spp. was 75.12% (163/217); 86.67% (104/120) of females and 60.82% (59/97) of males collected from red deer hunted in the Strzałowo Forest District in Poland (53°45'57.03″N, 21°25'17.79″E) were infected. The nucleotide sequences from 14 isolates (Bartonella sp. 1) showed close similarity to Bartonella schoenbuchensis isolated from moose blood from Sweden (GenBank: KB915628) and human blood from France (GenBank: HG977196); Bartonella sp. 2 (5 isolates) and Bartonella sp. 3 (one isolate) were similar to Bartonella sp. from Japanese sika deer (GenBank: AB703149), and Bartonella sp. 4 (one isolate) was almost identical to Bartonella sp. isolated from Japanese sika deer from Japan (GenBank: AB703146).

Conclusions: To the best of our knowledge, this is the first report to confirm the presence of Bartonella spp. in deer keds (Lipoptena cervi) in Poland by molecular methods. Bartonella sp. 1 isolates were most closely related to B. schoenbuchensis isolated from moose from Sweden and human blood from France. The rest of our isolates (Bartonella spp. 2-4) were similar to Bartonella spp. isolated from Japanese sika deer from Japan.

Keywords: Bartonella schoenbuchensis; Bartonella spp.; Cervus elaphus; Lipoptena cervi.

Fig. 1

Phylogenetic tree of Bartonella spp., constructed by Bayesian inference (BI) analysis using MrBayes version 3.2. For BI codon analysis (nucmodel = codon), the GTR + I + G model was chosen based on jModelTest version 2.1.4 [43, 44] using Akaike Information Criterion. Analysis was run for 8,000,000 generations, with 2,000,000 generations discarded as ‘burn-in’. Hosts, country and GenBank accession numbers of origin are shown. Nodal support is indicated as Bayesian posterior probabilities. Sequence from Brucella melitensis (AY562179) was used as outgroup. Sequences generated in this study are shown in bold