Bartonella Strains Research Articles

Diversity of bartonellae in mites (Acari: Mesostigmata: Macronyssidae and Spinturnicidae) of boreal forest bats: Association of host specificity of mites and habitat selection of hosts with vector potential.

Research into various bacterial pathogens that can be transmitted between different animals and may have zoonotic potential has led to the discovery of different strains of Bartonella sp. in bats and their associated ectoparasites. Despite their enormous species diversity, only a few studies have focussed on the detection of bacterial pathogens in insectivorous bats of boreal forests and their associated Macronyssidae and Spinturnicidae mites. We collected and molecularly analysed mite samples from forest-dwelling bat species distributed all along the boreal belt of the Palearctic, from Central Europe to Far East. Ectoparasitic mites were pooled for DNA extraction and DNA amplification polymerase chain reaction (PCRs) were conducted to detect the presence of various bacterial (Anaplasmataceae, Bartonella sp., Rickettsia sp., Mycoplasma sp.) and protozoal (Hepatozoon sp.) pathogens. Bartonella sp. DNA was detected in four different mite species (Macronyssidae: Steatonyssus periblepharus and Spinturnicidae: Spinturnix acuminata, Sp. myoti and Sp. mystacinus), with different prevalences of the targeted gene (gltA, 16-23S ribosomal RNA intergenic spacer and ftsZ). Larger pools (>5 samples pooled) were more likely to harbour Bartonella sp. DNA, than smaller ones. In addition, cave-dwelling bat hosts and host generalist mite species are more associated with Bartonella spp. presence. Spinturnicidae mites may transmit several distinct Bartonella strains, which cluster phylogenetically close to Bartonella species known to cause diseases in humans and livestock. Mites with ubiquitous presence may facilitate the long-term maintenance (and even local recurrence) of Bartonella-infestations inside local bat populations, thus acting as continuous reservoirs for Bartonella spp in bats.

Molecular Prevalence, Genetic Diversity, and Tissue Tropism of Bartonella Species in Small Mammals from Yunnan Province, China.

Bartonella is an intracellular parasitic zoonotic pathogen that can infect animals and cause a variety of human diseases. This study investigates Bartonella prevalence in small mammals in Yunnan Province, China, focusing on tissue tropism. A total of 333 small mammals were sampled from thirteen species, three orders, four families, and four genera in Heqing and Gongshan Counties. Conventional PCR and real-time quantitative PCR (qPCR) were utilized for detection and quantification, followed by bioinformatic analysis of obtained DNA sequences. Results show a 31.5% detection rate, varying across species. Notably, Apodemus chevrieri, Eothenomys eleusis, Niviventer fulvescens, Rattus tanezumi, Episoriculus leucops, Anourosorex squamipes, and Ochotona Thibetana exhibited infection rates of 44.4%, 27.7%, 100.0%, 6.3%, 60.0%, 23.5%, and 22.2%, respectively. Genetic analysis identified thirty, ten, and five strains based on ssrA, rpoB, and gltA genes, with nucleotide identities ranging from 92.1% to 100.0%. Bartonella strains were assigned to B. grahamii, B. rochalimae, B. sendai, B. koshimizu, B. phoceensis, B. taylorii, and a new species identified in Episoriculus leucops (GS136). Analysis of the different tissues naturally infected by Bartonella species revealed varied copy numbers across different tissues, with the highest load in spleen tissue. These findings underscore Bartonella's diverse species and host range in Yunnan Province, highlighting the presence of extensive tissue tropism in Bartonella species naturally infecting small mammalian tissues.

Case series of 12 Bartonella quintana endocarditis from the Southwest Indian Ocean.

Bartonella spp. are fastidious bacteria frequently identified as the cause of blood culture-negative (BCN) endocarditis. However, Bartonella infections are difficult to diagnose in routine laboratory testing and their incidence is probably underestimated. We investigated the epidemiological and clinical features of Bartonella endocarditis cases diagnosed between 2009 and 2021 on Reunion Island (Southwest Indian Ocean). We retrospectively included all patients diagnosed with Bartonella endocarditis at Reunion Island University Hospital during this period. Endocarditis was diagnosed on the basis of microbiological findings, including serological tests (IFA) and PCR on cardiac valves, and the modified Duke criteria. We used then the multispacer typing (MST) method to genotype the available Bartonella strains. We report 12 cases of B. quintana endocarditis on Reunion Island (83.3% in men, median patient age: 32 years). All the patients originated from the Comoros archipelago. The traditional risk factors for B. quintana infection (homelessness, alcoholism, exposure to body lice) were absent in all but two of the patients, who reported head louse infestations in childhood. Previous heart disease leading to valve dysfunction was recorded in 50% of patients. All patients underwent cardiac valve surgery and antimicrobial therapy with a regimen including doxycycline. All patients presented high C-reactive protein concentrations, anemia and negative blood cultures. The titer of IgG antibodies against Bartonella sp. exceeded 1:800 in 42% of patients. Specific PCR on cardiac valves confirmed the diagnosis of B. quintana endocarditis in all patients. Genotyping by the MST method was performed on four strains detected in preserved excised valves and was contributive for three, which displayed the MST6 genotype. Bartonella quintana is an important cause of infective endocarditis in the Comoros archipelago and should be suspected in patients with mitral valve dysfunction and BCN from this area.

Bartonella infections are prevalent in rodents despite efficient immune responses

BackgroundPathogens face strong selection from host immune responses, yet many host populations support pervasive pathogen populations. We investigated this puzzle in a model system of Bartonella and rodents from Israel’s northwestern Negev Desert. We chose to study this system because, in this region, 75–100% of rodents are infected with Bartonella at any given time, despite an efficient immunological response. In this region, Bartonella species circulate in three rodent species, and we tested the hypothesis that at least one of these hosts exhibits a waning immune response to Bartonella, which allows reinfections.MethodsWe inoculated captive animals of all three rodent species with the same Bartonella strain, and we quantified the bacterial dynamics and Bartonella-specific immunoglobulin G antibody kinetics over a period of 139 days after the primary inoculation, and then for 60 days following reinoculation with the same strain.ResultsContrary to our hypothesis, we found a strong, long-lasting immunoglobulin G antibody response, with protective immunological memory in all three rodent species. That response prevented reinfection upon exposure of the rodents to the same Bartonella strain.ConclusionsThis study constitutes an initial step toward understanding how the interplay between traits of Bartonella and their hosts influences the epidemiological dynamics of these pathogens in nature.Graphical

Bartonella Prevalence and Genome Sequences in Rodents in Some Regions of Xinjiang, China.

In this study, we investigated Bartonella infection and its genetic diversity in rodents in Beitun, Xinjiang Uygur Autonomous Region, China. Small mammals were captured using snap traps at four sampling sites in 2018. Spleen and liver tissues were collected and cultured to isolate Bartonella strains. Whole-genome sequencing was performed on the strains identified as Bartonella by gltA gene PCR, and the average nucleotide identity (ANI) of the genomes was calculated by using FastANI v1.33. Phylogenetic trees were constructed for the samples positive for Bartonella spp. by the gltA PCR assay based on 1,290-bp gltA genes, 2,903-bp rpoB genes, and core-genome single nucleotide polymorphisms (SNPs). Among 66 rodents, 11 were positive for Bartonella, with an infection rate of 16.67%. The rodent infection rates in different tissues (χ2 = 2.133; P = 0.242), species (χ2 = 9.631; P = 0.141), and habitats (χ2 = 4.309; P = 0.312) did not show statistical differences. Bartonella spp. isolated from the rodents were phylogenetically divided into six clades (two different Bartonella species were detected in two rodents). By comparing phylogenetic trees based on gltA genes, rpoB genes, and SNPs, we found that the topological structures of several evolutionary trees are different. However, the Bartonella strains isolated in this study were clustered into six clusters in different phylogenetic trees. Broad distributions and high genetic diversity of Bartonella strains were observed among rodents in Beitun, Xinjiang. IMPORTANCE Rodent-borne Bartonella species have been associated with zoonotic diseases. Bartonella species such as Bartonella elizabethae, Bartonella grahamii, and Bartonella tribocorum can cause disease in humans. Humans can be infected by blood-sucking arthropods through the scratches and bites of an infected reservoir host or via contact with infectious rodents. Xinjiang is one of the provinces with the most abundant species of Bartonella in China, but there are few reports about the prevalence of Bartonella in the Beitun area. This research aims to investigate the occurrence and prevalence of Bartonella infection in rodents at these sampling sites and provide a basis for the prevention and control of rodent Bartonella species in Beitun and the surrounding areas of Xinjiang.

Molecular detection of Rickettsia, Anaplasma, and Bartonella in ticks from free-ranging sheep in Gansu Province, China

Ticks pose a serious threat to public health as carriers and often vectors of zoonotic pathogens. There are few systematic studies on the prevalence and genetic diversity of tick-borne bacterial pathogens in Western China. In this study, 465 ticks were collected from free-ranging sheep in Gansu Province in China. Ticks were divided into 113 pools and tick DNA was extracted from these ticks. PCR assays were performed using specific primers to screen for tick-borne pathogens as well as sequence analysis based on the 16S rRNA (rrs), ompB, gltA, ompA genes for Rickettsia, rrs, groEL genes for Anaplasma, and ssrA and rpoB genes for Bartonella. The PCR results showed that the minimum infection rates with Rickettsia, Anaplasma, and Bartonella were 16.8% (78/465), 18.9% (88/465), and 0.9% (4/465), respectively. Sequence analysis based on the concatenated sequences of rrs-ompB-gltA-ompA indicated that the Rickettsia species identified in the ticks belonged to Rickettsia raoultii, Rickettsia slovaca, and Rickettsia sibirica, respectively; phylogenetic analysis based on the groEL gene showed that all Anaplasma strains identified were Anaplasma ovis; and phylogenetic analysis based on the ssrA and rpoB genes indicated that all Bartonella strains in the ticks belonged to Bartonella melophagi. The results of this study showed that ticks in Gansu Province harbored multiple pathogens that may cause rickettsial diseases and bartonellosis. These diseases were neglected in the area and physicians and public health workers need to pay attention to their diagnoses to prevent human infection.

Genomic Characterization of Three Novel Bartonella Strains in a Rodent and Two Bat Species from Mexico.

Rodents and bats are the most diverse mammal group that host Bartonella species. In the Americas, they were described as harboring Bartonella species; however, they were mostly characterized to the genotypic level. We describe here Bartonella isolates obtained from blood samples of one rodent (Peromyscus yucatanicus from San José Pibtuch, Yucatan) and two bat species (Desmodus rotundus from Progreso, and Pteronotus parnellii from Chamela-Cuitzmala) from Mexico. We sequenced and described the genomic features of three Bartonella strains and performed phylogenomic and pangenome analyses to decipher their phylogenetic relationships. The mouse-associated genome was closely related to Bartonella vinsonii. The two bat-associated genomes clustered into a single distinct clade in between lineages 3 and 4, suggesting to be an ancestor of the rodent-associated Bartonella clade (lineage 4). These three genomes showed <95% OrthoANI values compared to any other Bartonella genome, and therefore should be considered as novel species. In addition, our analyses suggest that the B. vinsonii complex should be revised, and all B. vinsonii subspecies need to be renamed and considered as full species. The phylogenomic clustering of the bat-associated Bartonella strains and their virulence factor profile (lack of the Vbh/TraG conjugation system remains of the T4SS) suggest that it should be considered as a new lineage clade (L5) within the Bartonella genus.

Genetic variations and microbiome of the poultry red mite Dermanyssus gallinae.

The poultry red mite Dermanyssus gallinae poses a significant threat to the health of hens and poultry production. A comprehensive understanding of D. gallinae is necessary to develop sustainable and efficacious control methods. Here we examined 144 D. gallinae collected from 18 poultry farms throughout the Japanese Archipelago for their genetic variations based on mitochondrial cytochrome c oxidase subunit I (COI) sequences, and microbiome variations based on amplicon sequencing of the 16S ribosomal RNA gene. According to COI sequencing, the Japanese samples were categorized into three haplogroups, which did not reflect the geographical distribution. Microbiome analyses found that the major bacteria associated with D. gallinae were Bartonella, Cardinium, Wolbachia, and Tsukamurella, with Bartonella being most predominant. Among 144 individual mites, all possessed one of the two major types of Bartonella (Bartonella sp. A), while 140 mites possessed the other type (Bartonella sp. B). The presence of the two strains of Bartonella was also confirmed by a single copy gene, rpoB. The presence of Bartonella in laid eggs suggested transovarial vertical transmission. Given that obligate blood-feeding arthropods generally require a supply of B vitamins from symbiotic bacteria, Bartonella may play an important role in mite survival. Rickettsiella, a major symbiont in European D. gallinae populations, and suggested to be an important symbiont by genomic data, was rarely found in Japanese populations. Cardinium detected from D. gallinae fell into a major clade found widely in arthropods, whereas Wolbachia detected in Japanese D. gallinae appear to be a new lineage, located at the base of Wolbachia phylogeny. Of the mitochondrial phylogeny, infection patterns of Cardinium and Wolbachia were strongly correlated, possibly suggesting one or both of the symbionts induce reproductive manipulations and increase spread in the host populations.

Bartonella choladocola sp. nov. and Bartonella apihabitans sp. nov., two novel species isolated from honey bee gut

Bartonella is one of the noncore bacterial genera in the honey bee (Apis mellifera) gut. So far, only one species, Bartonella apis, has been described from the honey bee gut. Previous analyses based on the genomic information of isolates and metagenome-assembled genomes suggested the existence of multiple Bartonella species in the bee guts. Here, 10 strains were isolated and characterized from the gut of A. mellifera from Jilin Province, China. New isolates shared ＞95% 16S rRNA gene sequence similarity with other species of the genus Bartonella. Phylogenetic analysis revealed that new isolates clustered with other type strains of Bartonella, and the bee gut Bartonella could be classified into three clades. The in silico DDH and average nucleotide identity values between strains of different clusters from the honey bee gut are 29.1–32.5% and 87.6–89.3%, all below the recommended 70.0% and 95% cutoff points. Cells are Gram-staining-negative rods and can grow on the surface of Brain Heart Infusion agar plates supplemented with defibrinated sheep blood in an aerobic environment with 5% CO2 at 35–37 °C. Strains from different species varied in both phenotypic and chemotaxonomic characterizations. Comparative genomic analysis indicated that B. choladocola had unique sets of genes encoding invasin, representing the potential for this species to both live as a gut symbiont and also as an erythrocytic pathogen. Thus, we propose two novel species Bartonella choladocola sp. nov. whose type strain is W8125T(=JCM 35030T = ACCC 62057T), and Bartonella apihabitans sp. nov. whose type strain is W8097T(=JCM 35029T = ACCC 62056T).

Bartonella spp. detection in laelapid (Mesostigmata: Laelapidae) mites collected from small rodents in Lithuania.

The genus Bartonella contains facultative Gram-negative intracellular bacteria from the family Bartonellaceae that can cause diseases in humans and animals. Various Bartonella species have been detected in rodents' ectoparasites, such as fleas, ticks, mites, and lice. However, the role of laelapid mites (Mesostigmata: Laelapidae) as carriers of Bartonella spp. needs to be confirmed. We aimed to investigate the presence of Bartonella spp. in laelapid mites collected from small rodents in Lithuania using real-time PCR targeting the transfer-messenger RNA/tmRNA (ssrA) gene and to characterize Bartonella strains using nested PCR and sequence analysis of the 16S-23S rRNA intergenic transcribed spacer region (ITS). A total of 271 laelapid mites of five species (Laelaps agilis, Haemogamasus nidi, Eulaelaps stabularis, Myonyssus gigas, and Hyperlaelaps microti) were collected from five rodent species (Apodemus flavicollis, Apodemus agrarius, Clethrionomys glareolus, Micromys minutus, and Microtus oeconomus) during 2015-2016. Bartonella DNA was detected in three mite species L. agilis, M. gigas, and Hg. nidi with an overall prevalence of 11.4%. Sequence analysis of the 16S-23S rRNA ITS region revealed the presence of Bartonella taylorii in L. agilis, Hg. nidi, and M. gigas, and Bartonella grahamii in L. agilis. Our results suggest that laelapid mites are involved in the maintenance of rodent-associated Bartonella spp. in nature. To the best of the authors' knowledge, this is the first study to demonstrate the presence of Bartonella spp. DNA in laelapid mites from small rodents.

Bartonella, Rickettsia, Babesia, and Hepatozoon Species in Fleas (Siphonaptera) Infesting Small Mammals of Slovakia (Central Europe).

Fleas (Siphonaptera) as obligate, blood-feeding ectoparasites are, together with ticks, hosted by small mammals and can transmit causative agents of serious infections. This study aimed to determine and characterize the presence and genetic diversity of Bartonella, Rickettsia, and apicomplexan parasites (Babesia, Hepatozoon) in fleas feeding on small mammals from three different habitat types (suburban, natural, and rural) in Slovakia. The most common pathogen in the examined fleas was Bartonella spp. (33.98%; 95% CI: 30.38–37.58), followed by Rickettsia spp. (19.1%; 95% CI: 16.25–22.24) and apicomplexan parasites (4.36%; 95% CI: 2.81–5.91). Bartonella strains belonging to B. taylorii, B. grahamii, B. elizabethae, Bartonella sp. wbs11, and B. rochalimae clades were identified in Ctenophthalmus agyrtes, C. congener, C. assimilis, C. sciurorum, C. solutus, C. bisoctodentatus, Palaeopsylla similis, Megabothris turbidus, and Nosopsyllus fasciatus within all habitats. The presence of Rickettsia helvetica, R. monacensis, and rickettsiae, belonging to the R. akari and R. felis clusters, and endosymbionts with a 96–100% identity with the Rickettsia endosymbiont of Nosopsyllus laeviceps laeviceps were also revealed in C. agyrtes, C. solutus, C. assimilis, C. congener, M. turbidus, and N. fasciatus. Babesia and Hepatozoon DNA was detected in the fleas from all habitat types. Hepatozoon sp. was detected in C. agyrtes, C. assimilis, and M. turbidus, while Babesia microti was identified from C. agyrtes, C. congener, and P. similis. The present study demonstrated the presence of zoonotic pathogens in fleas, parasitizing the wild-living small mammals of southwestern and central Slovakia and widens our knowledge of the ecology and genomic diversity of Bartonella, Rickettsia, Babesia, and Hepatozoon.

Ehrlichia, Coxiella and Bartonella infections in rodents from Guizhou Province, Southwest China

Rodents are generally recognized to be the reservoir hosts of a great many zoonotic pathogens. In some areas of China, rodent-borne pathogens, as well as the role of rodents in the natural cycle of these pathogens, are still poorly investigated. To increase our knowledge on the distribution and epidemiology of rodent-borne bacterial pathogens, 81 rodent liver samples were collected in three locations of Guizhou province located in Southwest China, and screened for the presence of Ehrlichia, Coxiella, and Bartonella in them. A putative novel Ehrlichia species was identified in 5 Berylmys bowersi samples (100%, 5/5). Its 16S rRNA, gltA, and groEL genes have highest 99.84%, 89.11%, and 98.02% identities to those from known Ehrlichia species, and form distinct clades in the phylogenetic trees. Herein we name it “Candidatus Ehrlichia zunyiensis”. Bartonella was tested positive in 8 A. agrarius (striped field mouse), 2 A. chevrieri (Chevrier's field mouse), 1 R. norvegicus (Norway rat), 1 N. confucianus, and 1 N. lotipes, with a total positive rate of 16.05% (13/81). Sequence analysis indicated high genetic diversity in these Bartonella strains. Unexpectedly, two Coxiella strains were identified from the rodents (1 Niviventer confucianus and 1 Mus pahari). Genetic and phylogenetic analysis indicated that both of them are closely related to the Coxiella endosymbiont of ticks. This result supported previous conjectures that vertebrate hosts such as rodents may play a role in the preservation and transmission of Coxiella endosymbiont of ticks.

Detection and genetic diversity of Bartonella species in small mammals from the central region of the Qinghai-Tibetan Plateau, China

In this study, we aimed to investigate the prevalence and molecular characteristics of Bartonella infections in small mammals from the central region of the Qinghai-Tibetan Plateau. Toward this, small mammals were captured using snap traps in Yushu City and Nangqian County, West China, and the spleen tissue was used for Bartonella culture. The suspected positive colonies were evaluated using polymerase chain reaction (PCR) amplification and by sequencing the citrate synthase (gltA) gene. We discovered that 31 out of the 103 small mammals tested positive for Bartonella, with an infection rate of 30.10%. Sex differences between the mammals did not result in a significant difference in infection rate (χ2 = 0.018, P = 0.892). However, there was a significant difference in infection rates in different small mammals (Fisher’s exact probability method, P = 0.017) and habitats (χ2 = 7.157, P = 0.028). Additionally, 31 Bartonella strains belonging to three species were identified, including B. grahamii (25), B. japonica (4) and B. heixiaziensis (2), among which B. grahamii was the dominant epidemic strain (accounting for 80.65%). Phylogenetic analyses showed that most of the B. grahamii isolates identified in this study may be closely related to the strains isolated from Japan and China. Genetic diversity analyses revealed that B. grahamii strains had high genetic diversity, which showed a certain host and geographical specificity. The results of Tajima’s test suggested that the B. grahamii followed the progressions simulated by a neutral evolutionary model in the process of evolution. Overall, a high prevalence and genetic diversity of Bartonella infection were observed in small mammals in the central region of the Qinghai-Tibetan Plateau. B. grahamii as the dominant epidemic strain may cause diseases in humans, and the corresponding prevention and control measures should be taken into consideration in this area.

Detection of Potential Zoonotic Bartonella Species in African Giant Rats (Cricetomys gambianus) and Fleas from an Urban Area in Senegal.

Bartonellae are bacteria associated with mammals and their ectoparasites. Rodents often host different species of Bartonella. The aim of this study was to investigate the presence of Bartonella spp. in African giant pouched rats (Cricetomys gambianus) and their ectoparasites in Dakar, Senegal. In 2012, 20 rats were caught, and their fleas were identified. DNA was extracted from 170 selected fleas and qPCR was carried out to detect Bartonella spp. Subsequently, a Bartonella culture was performed from the rat blood samples and the isolated strains (16S rRNA, rpoB, ftsZ and ITS3) were genotyped. A total of 1117 fleas were collected from 19 rats and identified as Xenopsylla cheopis, the tropical rat flea. Bartonella DNA was detected in 148 of 170 selected fleas (87.1%). In addition, Bartonella strains were isolated from the blood of 17 rats (85%). According to Bartonella gene-sequence-based criteria for species definition, the isolated strains were identified as B. massiliensis (four strains) and two potential new species related to the zoonotic B. elizabethae. In this paper, these potentially new species are provisionally called Candidatus Bartonella militaris (11 strains) and Candidatus Bartonella affinis (two strains) until their description has been completed. Cricetomys gambianus and its fleas could constitute a public health risk in Dakar due to the high prevalence of Bartonella infection reported.

Prevalence and Genetic Diversity of Bartonella Spp. in Northern Bats (Eptesicus nilssonii) and Their Blood-Sucking Ectoparasites in Hokkaido, Japan.

We investigated the prevalence of Bartonella in 123 northern bats (Eptesicus nilssonii) and their ectoparasites from Hokkaido, Japan. A total of 174 bat fleas (Ischnopsyllus needhami) and two bat bugs (Cimex japonicus) were collected from the bats. Bartonella bacteria were isolated from 32 (26.0%) of 123 bats. Though Bartonella DNA was detected in 79 (45.4%) of the bat fleas, the bacterium was isolated from only one bat flea (0.6%). The gltA sequences of the isolates were categorized into genotypes I, II, and III, which were found in both bats and their fleas. The gltA sequences of genotypes I and II showed 97.6% similarity with Bartonella strains from a Finnish E. nilssonii and a bat flea from a E. serotinus in the Netherlands. The rpoB sequences of the genotypes showed 98.9% similarity with Bartonella strain 44722 from E. serotinus in Republic of Georgia. The gltA and rpoB sequences of genotype III showed 95.9% and 96.7% similarity with Bartonella strains detected in shrews in Kenya and France, respectively. Phylogenetic analysis revealed that Bartonella isolates of genotypes I and II clustered with Bartonella strains from Eptesicus bats in Republic of Georgia and Finland, Myotis bats in Romania and the UK, and a bat flea from an Eptesicus bat in Finland. In contrast, genotype III formed a clade with B. florencae, B. acomydis, and B. birtlesii. These data suggest that northern bats in Japan harbor two Bartonella species and the bat flea serves as a potential vector of Bartonella transmission among the bats.

Impact of tick-borne Anaplasma phagocytophilum infections in calves of moose (Alces alces) in southern Norway.

The Gram-negative, obligate intracellular tick-transmitted pathogen Anaplasma phagocytophilum can cause acute febrile diseases in humans and domestic animals. The expansion of the tick Ixodes ricinus (Linnaeus, 1758) in northern Europe due to climate change is of serious concern for animal and human health. The aim of the present study was to investigate the impact of A. phagocytophilum infection in moose Alces alces (Linnaeus) calves by evaluating the carcass weights of infected and non-infected animals and examining animal tissues samples for co-infections with either species of Babesia Starcovici, 1893 or bacteria of the genus Bartonella. The carcasses of 68 free-ranging moose calves were weighed by hunters during the hunting seasons from 2014 to 2017 in two regions in southern Norway and spleen samples were collected. Anaplasma phagocytophilum was detected in moose sampled from locations infected with ticks with a prevalence of 82% (n = 46). The carcass weights of A. phagocytophilum-infected calves (n = 46) and non-infected (n = 22) calves were compared. Although the average weight of infected calves (45.6 kg) was lower than that of non-infected calves (46.5 kg), the difference was not statistically significant. Three different variants of the bacterium 16S rRNA gene were identified. The average weight of animals infected with variant I was 49.9 kg, whereas that of animals infected with variant III was 42.0 kg, but the difference was not statistically significant (p = 0.077). Co-infections of A. phagocytophilum with Bartonella spp. or with Babesia spp. were found in 20 and two calves, respectively. A triple infection was found in two calves. Sequence analysis of the 18S rRNA gene of Babesia-positive samples revealed the presence of Babesia cf. odocoilei (Emerson et Wright, 1970). Strains of Bartonella closely related to Bartonella bovis (Bermond, Boulouis, Heller, Laere, Monteil, Chomel, Sander, Dehio et Piemont, 2002) were identified based on phylogenetic analysis of the gltA and rpoB genes. The loss of body mass in moose calves in the tick-infected site was probably influenced by multiple factors.

New Records of Bartonella spp. and Rickettsia spp. in Lice Collected from Small Rodents.

Lice are blood-sucking insects that are of medical and veterinary significance as parasites and vectors for various infectious agents. More than half of described blood-sucking lice species are found on rodents. Rodents are important hosts of several Bartonella and Rickettsia species, and some of these bacteria are characterized as human pathogens in Europe. Rodent ectoparasites, such as fleas and ticks, are important vectors of Bartonella spp. and Rickettsia spp., but knowledge about the presence of these bacteria in lice is limited. The aim of this study was to determine the prevalence of Bartonella and Rickettsia bacteria in lice collected from rodents in Slovakia. The ectoparasites were collected from small rodents captured from 2010 to 2015 at four different sites in eastern Slovakia. The presence of Bartonella and Rickettsia species in lice samples was screened by real-time PCR, targeting ssrA and gltA genes, respectively. The molecular characterization of the Bartonella strains was based on sequence analysis of partial rpoB and intergenic spacer (ITS) genes, and of the Rickettsia species on sequence analysis of the gltA gene. A total of 1074 lice of seven species were collected from six rodent species. Bartonella DNA was detected in Hoplopleura affinis (collected from Apodemus agrarius, Apodemus flavicollis, and Myodes glareolus), Polyplax serrata (from A. agrarius), and Hoplopleura sp. (from A. flavicollis). Sequence analysis revealed that the Bartonella strains belonged to the Bartonella coopersplainsensis, Bartonella tribocorum, and Bartonella taylorii genogroups. Rickettsia DNA was detected in H. affinis and P. serrata collected from A. agrarius. Sequence analysis revealed two Rickettsia species: Rickettsia helvetica and Rickettsia sp. The results of the study confirm the presence of Bartonella spp. and Rickettsia spp. in lice collected from rodents.

Lipoptena fortisetosa as a vector of Bartonella bacteria in Japanese sika deer (Cervus nippon)

BackgroundTwo species of deer ked (Lipoptena cervi and L. mazamae) have been identified as vectors of Bartonella bacteria in cervids in Europe and the USA. In an earlier study we showed that Japanese sika deer (Cervus nippon) harbor three Bartonella species, namely B. capreoli (lineage A) and two novel Bartonella species (lineages B and C); however, there is currently no information on the vector of Bartonella bacteria in sika deer. The aim of this study was to clarify potential vectors of Bartonella in Japanese sika deer.MethodsThirty-eight wingless deer keds (L. fortisetosa) and 36 ticks (Haemaphysalis and Ixodes species) were collected from sika deer. The prevalence of Bartonella in the arthropods was evaluated by real-time PCR targeting the 16S−23S internal transcribed spacer (ITS) and by culture of the organisms. The total number of Bartonella bacteria were quantified using real-time PCR. The distribution of Bartonella bacteria in deer ked organs was examined by immunofluorescence analysis. The relationship of Bartonella strains isolated from sika deer and arthropods were examined by a phylogenetic analysis based on concatenated sequences of the gltA, rpoB, ftsZ, and ribC genes, followed by a BLAST search for gltA and rpoB.ResultsBartonella prevalence in deer keds was 87.9% by real-time PCR and 51.5% in culture and that in the ticks was 8.3% by real-time PCR and 2.8% in culture. The mean number of Bartonella bacteria per ked was calculated to be 9.2 × 105 cells. Bartonella aggregates were localized in the midgut of the keds. The phylogenetic analysis and BLAST search showed that both the host deer and the keds harbored two Bartonella species (lineages B and C), while B. capreoli (lineage A) was not detected in the keds. Two novel Bartonella species (lineages D and E) were isolated from one ked.ConclusionsLipoptena fortisetosa likely serves as a vector of at least two Bartonella species (lineages B and C), whereas ticks do not seem to play a significant role in the transmission of Bartonella between sika deer based on the lower detection rates of Bartonella in ticks compared to keds. Bartonella species in lineages D and E appear to be L. fortisetosa-specific strains.Graphical

Genetic diversity of Bartonella species in small mammals in the Qaidam Basin, western China

Investigation of the prevalence and diversity of Bartonella infections in small mammals in the Qaidam Basin, western China, could provide a scientific basis for the control and prevention of Bartonella infections in humans. Accordingly, in this study, small mammals were captured using snap traps in Wulan County and Ge’ermu City, Qaidam Basin, China. Spleen and brain tissues were collected and cultured to isolate Bartonella strains. The suspected positive colonies were detected with polymerase chain reaction amplification and sequencing of gltA, ftsZ, RNA polymerase beta subunit (rpoB) and ribC genes. Among 101 small mammals, 39 were positive for Bartonella, with the infection rate of 38.61%. The infection rate in different tissues (spleens and brains) (χ2 = 0.112, P = 0.738) and gender (χ2 = 1.927, P = 0.165) of small mammals did not have statistical difference, but that in different habitats had statistical difference (χ2 = 10.361, P = 0.016). Through genetic evolution analysis, 40 Bartonella strains were identified (two different Bartonella species were detected in one small mammal), including B. grahamii (30), B. jaculi (3), B. krasnovii (3) and Candidatus B. gerbillinarum (4), which showed rodent-specific characteristics. B. grahamii was the dominant epidemic strain (accounted for 75.0%). Furthermore, phylogenetic analysis showed that B. grahamii in the Qaidam Basin, might be close to the strains isolated from Japan and China. Overall, we observed a high prevalence of Bartonella infection in small mammals in the Qaidam Basin. B. grahamii may cause human disease, and the pathogenicity of the others Bartonella species needs further study, the corresponding prevention and control measures should be taken into consideration.

Bartonella spp. in Small Mammals and Their Fleas in Differently Structured Habitats From Germany.

Most Bartonella spp. are transmitted by fleas and harbored by small mammals which serve as reservoirs. However, little is known about the composition of fleas and their Bartonella spp. from small mammals in Central Europe. Therefore, the aims of this study were to investigate flea communities on small mammals from three differently structured sites (urban, sylvatic, renatured) in Germany as well as the prevalence of Bartonella spp. in small mammals and their parasitizing fleas. In total, 623 small mammals belonging to 10 different species (the majority were Myodes glareolus and Apodemus flavicollis) were available. Fleas were removed from the small mammals' fur, morphologically identified and DNA was extracted. To detect Bartonella spp., two conventional PCRs targeting the gltA gene and the 16S−23S rRNA intergenic spacer were carried out followed by sequencing. Obtained sequences were compared to those in GenBank. In total, 1,156 fleas were collected from 456 small mammals. Altogether, 12 different flea species (the majority were Ctenophthalmus agyrtes, Nosopsyllus fasciatus, and Megabothris turbidus) were detected. At the urban site mostly Leptopsylla segnis and N. fasciatus were collected which may be vectors of zoonotic pathogens to companion animals. The overall prevalence for Bartonella in small mammals was 43.3% and in fleas 49.1%. Five different Bartonella spp. were detected in small mammals namely B. grahamii, B. taylorii, B. doshiae, Bartonella sp. N40 and uncultured Bartonella sp. whereas in fleas four Bartonella spp. were found which were with the exception of B. doshiae identical to the Bartonella species detected in their small mammal hosts. While B. grahamii was the only zoonotic Bartonella sp. most Bartonella strains found in fleas and small mammals belonged to uncultured Bartonella spp. with unknown zoonotic potential. This study showed a high diversity of flea species on small mammals from Germany. Further, high prevalence rates of Bartonella species were detected both in fleas and in their mammalian hosts. Several different Bartonella species with a high genetic variability were discovered. Especially at the urban study sites, this may pose a risk for Bartonella transmission to companion animals and humans.