Infections with Bartonella spp. in free-ranging cervids and deer keds (Lipoptena cervi) in Norway

Molecular survey and phylogenetic analysis of Bartonella sp., Coxiella sp., and hemoplamas in pudu (Pudu puda) from Chile: first report of Bartonella henselae in a wild ungulate species

Introduction

Recent evidence shows a high diversity of infectious agents in wildlife that represent a threat to human, domestic, and wild animal health. In Chile, wild populations of the most common cervid species, pudu (Pudu puda), have been reported as hosts for novel pathogens such as Mycoplasma ovis-like and a novel ecotype of Anaplasma phagocytophilum. A better understanding of the epidemiology of this group and other intracellular bacteria that might have cervids as hosts would enlighten their population relevance. This study aimed to determine the occurrence and genetic diversity of Bartonella spp., hemotropic mycoplasmas, and Coxiella burnetii in pudus from Chile.

Methods

The DNA was extracted from the blood samples of 69 wild free-ranging and 30 captive pudus from Chile. A combination of real-time (nouG gene for Bartonella and IS1111 element for C. burnetii) and conventional PCR (16S rRNA for hemotropic Mycoplasma spp. and rpoB, gltA, and ITS for Bartonella spp.) was used for pathogen screening and molecular characterization.

Results

DNA of Bartonella spp. was detected in 10.1% [95% CI (5.2-18.2%)] samples, hemotropic Mycoplasma spp. in 1.7% [95% CI (0.08-10.1%)], and C. burnetii in 1.0% [95% CI (0.05-6.3%)] samples. Two sequenced samples were identified as Mycoplasma ovis-like, and one free-ranging pudu was positive for C. burnetii. While one captive and two free-ranging pudus were positive for Bartonella henselae, one wild pudu was co-positive for B. henselae and Bartonella sp., similar to Bartonellae identified in ruminants.

Discussion

To the best of our knowledge, this is the first report of B. henselae in wild ungulate species, and C. burnetii and Bartonella spp. in wild ungulate species in South America. Further research will be necessary to evaluate the potential role of pudu as reservoirs of infection and identify the sources for disease transmission among humans and wild and domestic animals.

Analysis of the bacterial communities associated with pupae and winged or wingless adults of Lipoptena fortisetosa collected from cervids in Italy

The hippoboscid Lipoptena fortisetosa Maa, 1965 is a hematophagous ectoparasite of cervids that can bite humans. This fly is expanding its geographical range and is of concern for animal and human health since it can potentially harbour harmful microorganisms. This study was aimed at characterizing the bacterial communities of L. fortisetosa in its different life-cycle stages. Pupae and wingless adults were collected from cervids hunted in Tuscan-Emilian Apennines (central Italy) and pooled into groups of 10 by life stage (30 individual pupae; 1420 individual wingless adults). Winged flies were caught by sweep netting and separated into five pools of 10 insects. After DNA extraction, the bacterial content of each pool was analysed using 16 S metabarcoding. Results revealed that the composition and relative abundance of different taxa greatly differed in the three analysed groups. Wingless adults showed a high abundance of Bartonella (33.07%), which is almost absent in winged flies and pupae. Among the detected pathogens, four genera of concern for human health were found: Bartonella, Moraxella, Mycobacterium and Rickettsia. Interestingly reads similar to Bartonella bovis, Moraxella osloensis and Arsenophonus lipopteni Operational Taxonomic Unit (OTUs) were detected. These findings suggest the possible role of L. fortisetosa as a reservoir of pathogenic microorganisms, confirming the need for further investigation to ascertain its vectorial capacity.

Molecular pathogen screening of louse flies (Diptera: Hippoboscidae) from domestic and wild ruminants in Austria

BACKGROUND

Hippoboscid flies (Diptera: Hippoboscidae), also known as louse flies or keds, are obligate blood-sucking ectoparasites of animals, and accidentally of humans. The potential role of hippoboscids as vectors of human and veterinary pathogens is being increasingly investigated, but the presence and distribution of infectious agents in louse flies is still unknown in parts of Europe. Here, we report the use of molecular genetics to detect and characterize vector-borne pathogens in hippoboscid flies infesting domestic and wild animals in Austria.

METHODS

Louse flies were collected from naturally infested cattle (n = 25), sheep (n = 3), and red deer (n = 12) across Austria between 2015 and 2019. Individual insects were morphologically identified to species level and subjected to DNA extraction for molecular pathogen screening and barcoding. Genomic DNA from each louse fly was screened for Borrelia spp., Bartonella spp., Trypanosomatida, Anaplasmataceae, Filarioidea and Piroplasmida. Obtained sequences of Trypanosomatida and Bartonella spp. were further characterized by phylogenetic and haplotype networking analyses.

RESULTS

A total of 282 hippoboscid flies corresponding to three species were identified: Hippobosca equina (n = 62) collected from cattle, Melophagus ovinus (n = 100) from sheep and Lipoptena cervi (n = 120) from red deer (Cervus elaphus). Molecular screening revealed pathogen DNA in 54.3% of hippoboscids, including infections with single (63.39%), two (30.71%) and up to three (5.90%) distinct pathogens in the same individual. Bartonella DNA was detected in 36.9% of the louse flies. Lipoptena cervi were infected with 10 distinct and previously unreported Bartonella sp. haplotypes, some closely associated with strains of zoonotic potential. DNA of trypanosomatids was identified in 34% of hippoboscids, including the first description of Trypanosoma sp. in H. equina. Anaplasmataceae DNA (Wolbachia spp.) was detected only in M. ovinus (16%), while < 1% of the louse flies were positive for Borrelia spp. and Filarioidea. All hippoboscids were negative for Piroplasmida.

CONCLUSIONS

Molecular genetic screening confirmed the presence of several pathogens in hippoboscids infesting domestic and wild ruminants in Austria, including novel pathogen haplotypes of zoonotic potential (e.g. Bartonella spp.) and the first report of Trypanosoma sp. in H. equina, suggesting a potential role of this louse fly as vector of animal trypanosomatids. Experimental transmission studies and expanded monitoring of hippoboscid flies and hippoboscid-associated pathogens are warranted to clarify the competence of these ectoparasites as vectors of infectious agents in a One-Health context.

First Molecular Detection of Bartonella bovis and Bartonella schoenbuchensis in European Bison (Bison bonasus)

Bartonella bacteria infect the erythrocytes and endothelial cells of mammalians. The spread of the Bartonella infection occurs mainly via bloodsucking arthropod vectors. Studies on Bartonella infection in European bison, the largest wild ruminant in Europe, are lacking. They are needed to clarify their role in the maintenance and transmission of Bartonella spp. The aim of this study was to investigate the presence of the Bartonella pathogen in European bison and their ticks in Lithuania. A total of 38 spleen samples from bison and 258 ticks belonging to the Ixodes ricinus and Dermacentor reticulatus species were examined. The bison and tick samples were subjected to ssrA, 16S-23S rRNA ITS, gltA, and rpoB partial gene fragment amplification using various variants of PCR. Bartonella DNA was detected in 7.9% of the tissue samples of European bison. All tick samples were negative for Bartonella spp. The phylogenetic analysis of 16S-23S rRNA ITS, gltA, and rpoB partial gene fragment revealed that European bison were infected by B. bovis (2.6%) and B. schoenbuchensis (5.3%). This is the first report addressing the occurrence of B. bovis and B. schoenbuchensis in European bison in Europe.

Prevalence and predictors of vector-borne pathogens in Dutch roe deer

BACKGROUND

The main objective of this study was to determine the prevalence of nine vector-borne pathogens or pathogen genera in roe deer (Capreolus capreolus) in the Netherlands, and to identify which host variables predict vector-borne pathogen presence in roe deer. The host variables examined were the four host factors 'age category', 'sex', 'nutritional condition' and 'health status', as well as 'roe deer density'.

METHODS

From December 2009 to September 2010, blood samples of 461 roe deer were collected and analysed by polymerase chain reaction (PCR) for the presence of genetic material from Anaplasma phagocytophilum, Bartonella spp., Babesia spp., Borrelia burgdorferi sensu lato (s.l.), Borrelia miyamotoi, Neoehrlichia mikurensis, Rickettsia spp., and epizootic haemorrhagic disease virus (EHDV), and by commercial enzyme-linked immunosorbent assay (ELISA) for antibodies against bluetongue virus (BTV). The possible associations of host factors and density with pathogen prevalence and co-infection, and in the case of A. phagocytophilum with bacterial load, were assessed using generalized linear modelling.

RESULTS AND CONCLUSION

Analysis revealed the following prevalence in roe deer: A. phagocytophilum 77.9%, Bartonella spp. 77.7%, Babesia spp. 17.4%, Rickettsia spp. 3.3%, B. burgdorferi sensu lato 0.2%. Various co-infections were found, of which A. phagocytophilum and Bartonella spp. (49.7% of infected roe deer) and A. phagocytophilum, Bartonella spp. and Babesia spp. (12.2% of infected roe deer) were the most common. Anaplasma phagocytophilum, Babesia spp., and co-infection prevalence were significantly higher in calves than in adult roe deer, whereas the prevalence of Bartonella spp. was lower in roe deer in good nutritional condition than in deer in poor nutritional condition. Local roe deer density was not associated with pathogen presence. The high prevalence of A. phagocytophilum, Bartonella spp., and Babesia spp. is evidence for the role of roe deer as reservoirs for these pathogens. Additionally, the results suggest a supportive role of roe deer in the life-cycle of Rickettsia spp. in the Netherlands.

Bartonella Infections in Cats and Cat Fleas in Lithuania

Bartonella are vector-borne parasitic bacteria that cause zoonotic infections in humans. One of the most common infections is cat-scratch disease caused by Bartonella henselae and Bartonella clarridgeiae. Cats are the major reservoir for these two species of bacteria, while cat fleas are vectors for the transmission of infection agents among cats. The aim of the present study was to investigate the presence of Bartonella infections in stray and pet cats and in cat fleas in Lithuania. Blood samples were taken from 163 cats presented in pet clinics and animal shelters. A total of 102 fleas representing two species, Ctenocephalides felis and Ctenocephalides canis, were collected from 12 owned cats that live both outdoors and indoors. Bartonella DNA in samples was detected using a nested PCR targeting the 16S–23S rRNA intergenic spacer (ITS) region. Bartonella DNA was detected in 4.9% (8/163) of the cats and 29.4% (30/102) of the fleas. Sequence analysis of the ITS region showed that the cats and fleas were infected with B. henselae, B. clarridgeiae and Bartonella sp., closely related to B. schoenbuchensis. This study is the first report on the prevalence and molecular characterization of Bartonella spp. in cats and cat fleas in Lithuania.

Molecular Evidence of Bartonella melophagi in Ticks in Border Areas of Xinjiang, China

Bartonella are gram-negative intracellular bacteria; certain species of Bartonella can cause diseases in mammals and humans. Ticks play a major role in the transmission of Bartonella. Xinjiang is the largest province in China according to land area and has one-third of the tick species in China; the infection rate of Bartonella in ticks in the Xinjiang border areas has not been studied in detail. Therefore, this study investigated tick infections by Bartonella in Xinjiang border areas, and the purpose of the study was to fill in gaps in information regarding the genetic diversity of tick infections by Bartonella in Xinjiang. We tested 1,549 tick samples from domestic animals (sheep and cattle) for Bartonella using ribC-PCR. Positive samples from the ribC-PCR assay for Bartonella spp. were further subjected to PCR assays targeting the ITS, rpoB and gltA genes followed by phylogenetic analyses. Bartonella DNA was detected in 2.19% (34/1,549) of tick samples, and the ITS, rpoB and gltA genes of ribC gene-positive samples were amplified to identify nine samples of Bartonella melophagi. In this study, molecular analysis was used to assess the presence and genetic diversity of B. melophagi in ticks collected from sheep and cattle from Xinjiang, China. This study provides new information on the presence and identity of B. melophagi in ticks from sheep and cattle.

Two New Haplotypes of Bartonella sp. Isolated from Lipoptena fortisetosa (Diptera: Hippoboscidae) in SE Poland

Simple Summary

Lipoptena fortisetosa is a hematophagous ectoparasite of game animals feeding accidentally on companion animals and humans. Since the presence of numerous pathogenic microorganisms has been described in this species, monitoring its geographic distribution is of great epidemiological importance. To the best of our knowledge, we present two new haplotypes of Bartonella sp. isolated from L. fortisetosa in south-eastern Poland and confirm the presence of this invasive species in Lublin Voivodeship since 2013.

Abstract

Insects of the genus Lipoptena are parasitic arthropods with a broad host range. Due to the type of parasitism (hematophagy), their potential role as vectors of pathogens, i.e., Bartonella sp., Anaplasma phagocytophilum, Rickettsia spp., and Borrelia burgdorferi is considered. As the range of their occurrence has been changing dynamically in recent years and infestations of humans have increasingly been reported, these organisms are now the subject of numerous studies. Our research aimed to present the molecular characteristics of Bartonella sp. detected in Lipoptena fortisetosa parasitizing wild cervids in south-eastern Poland. Adults of Lipoptena spp. were collected from carcasses of roe deer and red deer between spring and autumn in 2013. The PCR method was used to detect Bartonella sp. in the insects. We report two new haplotypes of the rpoB gene of Bartonella sp. isolated from L. fortisetosa feeding on wild cervids in south-eastern Poland and the presence of this invasive ectoparasitic species in the studied area since 2013. Phylogenetic analyses of newly obtained Bartonella sp. haplotypes confirmed their unique position on the constructed tree and network topology. The rpoB gene sequences found belonging to lineage B support the view that this phylogenetic lineage represents a novel Bartonella species.

Keds, the enigmatic flies and their role as vectors of pathogens

Hippoboscid flies (Diptera: Hippoboscidae), commonly known as keds or louse flies, have been for long time overlooked by the scientific community, and their vector role of infectious agents to humans and domestic animals has been scantly investigated. This is partly due to the fact that the host range for most species is primarily restricted to wildlife, being rarely reported on domestic animals and humans. This led to a scarce scientific knowledge about their biology, ecology, behaviour, epidemiology as well as vector competence. However, the life history of some hippoboscid species, e.g., Melophagus ovinus, Lipoptena cervi and Hippobosca equina, suggests that these ectoparasites are important candidates to vector infectious disease agents (e.g., Rickettsia spp., Borrelia spp., Bartonella spp., Anaplasma phagocytophilum, Theileria ovis). Indeed, the peculiar biological and behavioural traits (i.e., obligatory blood sucking and reproductive physiology) of many ked species make them a suitable pabulum for pathogen's multiplication and for their transmission to receptive hosts. Therefore, studies focusing on the ked bio-ecological aspects as well as on their vector role are advocated along with the control of keds affecting different animal species. This review discusses current information on keds, highlighting their importance as vectors of pathogens of medical and veterinary concern to all animal species, with a special focus on mammals.

Molecular detection and genetic diversity of Bartonella species in large ruminants and associated ectoparasites from the Brazilian Cerrado

Currently, five Bartonella species and an expanding number of Candidatus Bartonella species have globally been reported in ruminants. Likewise, different Bartonella genotypes were identified. However, studies relating to ruminant-associated Bartonella in Brazil are scarce. The current study aimed to assess the prevalence and genetic diversity of Bartonella in cattle, buffaloes and associated ectoparasites in Brazil. For this purpose, EDTA-blood samples from 75 cattle and 101 buffaloes were sampled. Additionally, 128 Rhipicephalus microplus and one Amblyomma sculptum ticks collected from cattle, and 197 R. microplus, one A. sculptum and 170 lice (Haematopinus tuberculatus) collected from buffaloes were included. Bartonella DNA was initially screened through an HRM real-time PCR assay targeting the 16S-23S internal transcribed spacer (ITS), and the positive samples were submitted to an additional HRM assay targeting the ssrA gene. The HRM-positive amplicons were sequenced, and the nucleotide identity was assessed by BLASTn. Bartonella spp.-positive DNA samples were analysed by conventional PCR assays targeting the gltA and rpoB genes, and then, the samples were cloned. Finally, the phylogenetic positioning and the genetic diversity of clones were assessed. Overall, 21 of 75 (28%) cattle blood samples and 13 of 126 (10.3%) associated ticks were positive for Bartonella bovis. Out of 101 buffaloes, 95 lice and 188 tick DNA samples, one (1%) buffalo and four (4.2%) lice were positive for Bartonella spp. Conversely, none of the ticks obtained from buffaloes were positive for Bartonella. The Bartonella sequences from buffaloes showed identity ranging from 100% (ITS and gltA) to 94% (ssrA) with B. bovis. In contrast, the Bartonella DNA sequences from lice were identical (100%) to uncultured Bartonella sp. detected in cattle tail louse (Haematopinus quadripertusus) from Israel in all amplified genes. The present study demonstrates the prevalence of new B. bovis genotypes and a cattle lice-associated Bartonella species in large ruminants and their ectoparasites from Brazil. These findings shed light on the distribution and genetic diversity of ruminant- and ectoparasite-related Bartonella in Brazil.

Bartonella spp. detection in ticks, Culicoides biting midges and wild cervids from Norway

Bartonella spp. are fastidious, gram-negative, aerobic, facultative intracellular bacteria that infect humans, and domestic and wild animals. In Norway, Bartonella spp. have been detected in cervids, mainly within the distribution area of the arthropod vector deer ked (Lipoptena cervi). We used PCR to survey the prevalence of Bartonella spp. in blood samples from 141 cervids living outside the deer ked distribution area (moose [Alces alces, n = 65], red deer [Cervus elaphus, n = 41] and reindeer [Rangifer tarandus, n = 35]), in 44 pool samples of sheep tick (Ixodes ricinus, 27 pools collected from 74 red deer and 17 from 45 moose) and in biting midges of the genus Culicoides (Diptera: Ceratopogonidae, 120 pools of 6,710 specimens). Bartonella DNA was amplified in moose (75.4%, 49/65) and in red deer (4.9%, 2/41) blood samples. All reindeer were negative. There were significant differences in Bartonella prevalence among the cervid species. Additionally, Bartonella was amplified in two of 17 tick pools collected from moose and in 3 of 120 biting midge pool samples. The Bartonella sequences amplified in moose, red deer and ticks were highly similar to B. bovis, previously identified in cervids. The sequence obtained from biting midges was only 81.7% similar to the closest Bartonella spp. We demonstrate that Bartonella is present in moose across Norway and present the first data on northern Norway specimens. The high prevalence of Bartonella infection suggests that moose could be the reservoir for this bacterium. This is the first report of bacteria from the Bartonella genus in ticks from Fennoscandia and in Culicoides biting midges worldwide.

Comparison of Skin Lesions Caused by Ixodes ricinus Ticks and Lipoptena cervi Deer Keds Infesting Humans in the Natural Environment

Background: The territorial expansion and increased population size of haematophagous arthropods (i.e., the castor bean tick Ixodes ricinus (Ixodida: Ixodidae) and the deer ked Lipoptena cervi (Diptera: Hippoboscidae)) has enhanced the risk of human infestations in Europe. The aim of our study was to present skin lesions induced by tick and deer ked bites in patients from recreational forest regions in southeastern Poland and pay attention to features of skin changes that may be useful in differential diagnosis. Methods: We compare the skin lesions after I. ricinus and L. cervi bite and draw attention to the biological and ecological traits of both ectoparasites, which may be diagnostically relevant for determination of the cause of skin symptoms reported by patients. Results: I. ricinus bites lead to development of erythematous-infiltrative poorly demarcated lesions with a centrally located bite mark, which usually disappears within one to several days. In turn, L. cervi bites leave irregularly shaped scattered erythematous papules. The papules may persist for up to one year and are accompanied by itching. Conclusions: Correct assessment of the clinical picture and its association with an arthropod bite (e.g., tick or deer ked) is highly important for further diagnostic procedures (i.e., differentiation of skin lesions developing in tick-borne diseases and, consequently, correct choice of pharmacological therapy). I. ricinus and L. cervi differ in their developmental cycles and rhythms of activity, which indicates that both species should be considered potential causative agents in the differential diagnosis of skin lesions when the patient has been bitten by an arthropod in autumn and winter months.