Zoonotic Bartonella Research Articles

Viable but nonculturable state in the zoonotic pathogen Bartonella henselae induced by low-grade fever temperature and antibiotic treatment

Viable but nonculturable state in the zoonotic pathogen Bartonella henselae induced by low-grade fever temperature and antibiotic treatment

Epidemiological survey and genetic diversity of Bartonella in fleas collected from rodents in Fujian Province, Southeast China

BackgroundFleas, considered to be the main transmission vectors of Bartonella, are highly prevalent and show great diversity. To date, no investigations have focused on Bartonella vectors in Southeast China. The aim of this study was to investigate the epidemiological and molecular characteristics of Bartonella in fleas in Southeast China.MethodsFrom 2016 to 2022, flea samples (n = 1119) were collected from 863 rodent individuals in seven inland and coastal cities in Southeast China. Flea species, region, gender, host species and habitat were recorded. The DNA samples from each individual flea were screened by real-time PCR for the Bartonella ssrA gene. All positive samples were confirmed by PCR based on the presence of the gltA gene and sequenced. The factors associated with Bartonella infection were analyzed by the Chi-square test and Fisher's exact test. ANOVA and the t-test were used to compare Bartonella DNA load.ResultsBartonella DNA was detected in 26.2% (293/1119) of the flea samples, including in 27.1% (284/1047) of Xenopsylla cheopis samples, 13.2% (5/38) of Monopsyllus anisus samples, 8.3% (2/24) of Leptopsylla segnis samples and 20.0% (2/10) of other fleas (Nosopsyllus nicanus, Ctenocephalides felis, Stivalius klossi bispiniformis and Neopsylla dispar fukienensis). There was a significant difference in the prevalence of Bartonella among flea species, sex, hosts, regions and habitats. Five species of Bartonella fleas were identified based on sequencing and phylogenetic analyses targeting the gltA gene: B. tribocorum, B. queenslandensis, B. elizabethae, B. rochalimae and B. coopersplainsensis.ConclusionsThere is a high prevalence and diversity of Bartonella infection in the seven species of fleas collected in Southeast China. The detection of zoonotic Bartonella species in this study, including B. tribocorum, B. elizabethae and B. rochalimae, raises public health concerns.Graphical

Detection of Bartonella in kissing bugs Triatoma rubrofasciata collected from Huizhou City, South China

BackgroundThe blood-feeding behavior of kissing bugs (subfamily Triatominae, family Reduviidae, order Hemiptera) means they are potential vectors of multiple humans pathogens. However, investigations of vector-borne pathogens harbored by kissing bugs are rare. MethodsIn the current study, 22 adult kissing bugs (Triatoma rubrofasciata) were captured in Huizhou City, Guangdong Province, south China. The presence of vector-borne pathogens in the kissing bugs was tested, and the genetic diversity of these potential pathogens was investigated. ResultsAll the kissing bugs were negative for Anaplasmataceae bacteria, Rickettsia, and Coxiella. Bartonella DNA was detected in 36.4% (8/22) of the kissing bugs. The sequences of the Bartonella gltA genes divided into two clades in a phylogenetic tree, with close relationships to B. tribocorum and uncultured Bartonella sp. clone MYR-283, respectively. All the groEL sequences were closely related to those of B. kosoyi (identity 98.75%–100%). The ftsZ and rpoB sequences were most closely related to those of B. elizabethae, a recognized human pathogen, with nucleotide similarities of 98.70%–100% and 99.45%–100%, respectively. ConclusionsWe report the detection of Bartonella DNA in Triatoma kissing bugs in southern China. Although the sample size is limited, the high positive rate of detection of Bartonella DNA, the close relationship of the gene sequences to those of zoonotic Bartonella species, and the distribution of the kissing bugs near human residences, hint at a risk to public health.

Molecular detection and characterization of Bartonella spp. in rodents from central and southern Chile, with emphasis on introduced rats (Rattus spp.)

Bartonella spp. was screened in 155 rodents from Chile, mainly the invasive rats Rattus norvegicus and Rattus rattus. A total of 155 spleen and 50 blood samples were analyzed through real-time PCR for Bartonella spp. (nuoG gene). Positive samples were subjected to amplification of fragment of loci gltA, rpoB and ITS by conventional PCR (cPCR). Overall, 43 spleen samples (27.7%) and 6 rodent blood samples (12%) were positive for nuoG-Bartonella spp. Positive samples were found in R. norvegicus, R. rattus, Abrothrix olivacea and Oligoryzomys longicaudatus. Bartonella spp. DNA was amplified by cPCR in 16 samples, resulting in 21 sequences (6 gltA, 5 ITS and 10 rpoB). Sequencing and phylogenic analyses identified genotypes from Rattus spp., potentially belonging to Bartonella coopersplainsensis, Bartonella henselae, Bartonella tribocorum, and an undescribed Bartonella sp. From native rodents, one sequence was identified, being related B. machadoae. In conclusion, this work describes diverse and potentially zoonotic Bartonella spp. genotypes in Rattus spp. Additionally, this is the first report of Bartonella in O. longicaudatus, including a potentially novel Bartonella genotype or species.

The association of host and vector characteristics with Ctenocephalides felis pathogen and endosymbiont infection.

Surveillance of the fleas and flea-borne pathogens infecting cats is important for both human and animal health. Multiple zoonotic Bartonella and Rickettsia species are known to infect the most common flea infesting cats and dogs worldwide: Ctenocephalides felis, the cat flea. The ability of other flea species to transmit pathogens is relatively unexplored. We aimed to determine cat host and flea factors independently associated with flea Bartonella and Rickettsia infection. We also assessed flea and cat infection by flea-host pair and location. To accomplish these aims, we performed qPCR for the detection of Bartonella, hemotropic Mycoplasma, Rickettsia, and Wolbachia DNA using paired cat and flea samples obtained from free-roaming cats presenting for spay or neuter across four locations in the United States. A logistic regression model was employed to identify the effect of cat (sex, body weight, geographic location, and Bartonella, hemotropic Mycoplasma, and Rickettsia spp., infection) and flea (clade and Rickettsia and Wolbachia infection) factors on C. felis Bartonella clarridgeiae infection. From 189 free roaming cats, we collected 84 fleas: Ctenocephalides felis (78/84), Cediopsylla simplex (4/84), Orchopeas howardi (1/84), and Nosopsyllus fasciatus (1/84). Ctenocephalides felis were phylogenetically assigned to Clades 1, 4, and 6 by cox1 gene amplification. Rickettsia asembonensis (52/84) and B. clarridgeiae (16/84) were the most common pathogenic bacteria detected in fleas. Our model identified host cat sex and weight as independently associated with B. clarridgeiae infection in fleas. Rickettsia asembonensis (52/84), Rickettsia felis (7/84) and Bartonella henselae (7/84) were detected in specific clades: R. felis was detected only in Clades 1 and 6 while B. henselae and R. asembonensis were detected only in Clade 4. Wolbachia spp., also displayed clade specificity with strains other than Wolbachia wCfeT only infecting fleas from Clade 6. There was poor flea and host agreement for Bartonella spp., infection; however, there was agreement in the Bartonella species detected in cats and fleas by geographic location. These findings reinforce the importance of considering reservoir host attributes and vector phylogenetic diversity in epidemiological studies of flea-borne pathogens. Widespread sampling is necessary to identify the factors driving flea-borne pathogen presence and transmission.

Prevalence of Bartonella spp., haemotropic Mycoplasma spp. and others vector-borne pathogens in private-owned dogs and cats, Egypt

Vector-borne pathogens have been increasingly investigated for their impact on dog and cat health and their zoonotic potential. The aim of this study was to investigate the prevalence estimates of selected vector-borne pathogens in client-owned pets from the Giza and Cairo governorates, Egypt. Out of 200 dogs and 100 cats, 94 (47%) and 23 (23%) were positive for at least one of the tested pathogens (P<0.0001). In particular, 84 (42%) dogs and 3 (3%) cats tested PCR-positive for Bartonella spp. (P<0.0001). A significantly higher prevalence of Bartonella spp. was detected in dogs from the rural areas of the Giza governorate (60/77, 79.2%, P<0.0001) compared to those from Cairo governorate. Bartonella henselae was the dominant species infecting dogs (81/200, 40.5%) followed by Candidatus Bartonella merieuxii (3/200, 1.5%), while B. henselae (2/100, 2%) and B. clarridgeiae were rare in cats. Haemoplasma DNA was detected in 17% (34/200) of dogs and 20% (20/100) of cats with increased risk in dogs from Giza rural areas (21/77, 27.27%, P=0.002) and from both dogs (16/63, 25.40%, P=0.03) and cats (7/14, 50%, P<0.002) with anemia. Candidatus Mycoplasma haematoparvum (30/200, 15%) and Mycoplasma haemocanis (4/200, 2%) in dogs and Candidatus Mycoplasma haemominutum (18/100, 18%) and M. haemofelis (2/100, 2%) in cats were detected. Additionally, 2 dogs were positive for C. burnetii DNA. Coinfections were detected in dogs, with the majority (23/200, 11.5%) including B. henselae and C.M. haematoparvum, followed by Mycoplasma haemocanis and C.M. haematoparvum (2/200, 1%) and B. henselae, CMhp and C. burnetii (2/200, 1%). Haemoplasma infection was high in Egyptian dogs and cats with a high prevalence for zoonotic Bartonella spp. in dogs with anemia, highlighting the need to investigate these agents in the diagnostic algorithm of anemia and to adopt preventive measures to protect both animal and human health.

Molecular detection and identification of Bartonella species in cats from Hamedan and Kermanshah, Western Iran

Bartonella species are emerging vector-borne zoonotic pathogens which infect a wide range of domestic and wild animals as well as humans. Cats are the primary reservoir hosts for several zoonotic Bartonella spp., the most common being B. henselae the causative agent of cat scratch disease. Despite the important role of cats in the epidemiology of bartonellosis, there is limited information about the prevalence and species infecting cats in Iran. The aim of present study was molecular detection and identification of Bartonella species in cats from two western provinces Hamedan and Kermanshah. From December 2018 to February 2021, 87 cats (n = 26 from Hamedan, n = 61 from Kermanshah) were examined clinically, their bodies were searched for collection of ectoparasites, and cephalic or saphenous blood specimens were collected. Genomic DNA was extracted from blood specimens and conventional PCRs targeting the rpoB, and ITS regions of Bartonella spp. were performed. Positive samples were sequenced and analysed phylogenetically. Bartonella DNA was detected in 11/87 cats (12.64 %). Sequencing results revealed the presence of B. henselae in cats from Hamedan, and B. clarridgeiae and B. henselae in cats from Kermanshah. A statistical association between cat origin and the prevalence of Bartonella spp. was observed in the studied population. This study confirms for the first time the circulation of Bartonella spp. in cats in two western Iranian provinces. Prevention strategies e.g. ectoparasites control, and regular examination of pet and urban cats are suggested for minimising Bartonella infection in cats and subsequently in humans.

Bartonella taylorii: A Model Organism for Studying Bartonella Infection in vitro and in vivo.

Bartonella spp. are Gram-negative facultative intracellular pathogens that infect diverse mammals and cause a long-lasting intra-erythrocytic bacteremia in their natural host. These bacteria translocate Bartonella effector proteins (Beps) into host cells via their VirB/VirD4 type 4 secretion system (T4SS) in order to subvert host cellular functions, thereby leading to the downregulation of innate immune responses. Most studies on the functional analysis of the VirB/VirD4 T4SS and the Beps were performed with the major zoonotic pathogen Bartonella henselae for which efficient in vitro infection protocols have been established. However, its natural host, the cat, is unsuitable as an experimental infection model. In vivo studies were mostly confined to rodent models using rodent-specific Bartonella species, while the in vitro infection protocols devised for B. henselae are not transferable for those pathogens. The disparities of in vitro and in vivo studies in different species have hampered progress in our understanding of Bartonella pathogenesis. Here we describe the murine-specific strain Bartonella taylorii IBS296 as a new model organism facilitating the study of bacterial pathogenesis both in vitro in cell cultures and in vivo in laboratory mice. We implemented the split NanoLuc luciferase-based translocation assay to study BepD translocation through the VirB/VirD4 T4SS. We found increased effector-translocation into host cells if the bacteria were grown on tryptic soy agar (TSA) plates and experienced a temperature shift immediately before infection. The improved infectivity in vitro was correlating to an upregulation of the VirB/VirD4 T4SS. Using our adapted infection protocols, we showed BepD-dependent immunomodulatory phenotypes in vitro. In mice, the implemented growth conditions enabled infection by a massively reduced inoculum without having an impact on the course of the intra-erythrocytic bacteremia. The established model opens new avenues to study the role of the VirB/VirD4 T4SS and the translocated Bep effectors in vitro and in vivo.

Threat under cats' claws: Molecular detection and risk factors for zoonotic Bartonella species in blood and claw samples from cats in Brazil

Bartonelloses are zoonoses widely dispersed throughout the world caused by bacteria of the genus Bartonella. Domestic cats play an important role in the epidemiology of bartonelloses, since these animals are considered natural hosts of B. henselae, B. koehlerae and B. clarridgeiae. This study aimed to determine the occurrence of Bartonella spp. in domestic cats’ blood and claw samples in the southern region of Bahia, northeastern Brazil. Additionally, the main clinical and hematological changes in Bartonella-positive animals were investigated, as well as the risk factors associated with the infection. For this purpose, 188 indoor house domestic cats were clinically evaluated and submitted to claw and blood sample collection. Additionally, data regarding the clinical history of the animals were recorded. Out of 188 cats’ blood samples, 20.7% (39/188) were positive in the qPCR for Bartonella spp. based on the nuoG gene. Out of 39 claw samples collected, 23.9% (9/39) were positive for Bartonella spp. The parameters of the blood and claw samples ranged from 1.42 to 395,000 and 4.32 - 108,000 copies/μL of a fragment of Bartonella nuoG gene, respectively. The amplified sequences shared identity ranging from 99% to 100% with the three main cat-related Bartonella species. Higher platelet values (p = 0.0082) were observed in animals positive for Bartonella spp. Young and unsterilized cats with outdoor access were more prone to infection by Bartonella spp. The data reported here demonstrated the occurrence of Bartonella spp. in blood and claw samples from cats in northeastern Brazil showing no significant clinical and hematological disorders.

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.

Epidemiological characteristics and genetic diversity of Bartonella species in rodents from southeastern China.

Rodents are the primary hosts of Bartonella species and carry more than 22 Bartonella species. However, the information on epidemiological characteristics and genetic diversity of Bartonella species in rodents in southeastern China is limited. From 2015 to 2020, 1,137 rodents were captured. Bartonella-positive DNA was detected in 14.9% (169/1,137) of rodents by PCR for both the ssrA and gltA genes. A highest Bartonella prevalence was detected in Apodemus agrarius (33.5%) and lowest in B.indica (1.8%). The probability of Bartonella infection in summer (20.1%) was higher than in spring (14.6%; p=.011, OR=1.756). Sequencing and phylogenetic analysis revealed that nine known Bartonella species were identified in rodents, including B.tribocorum, B.grahamii, B.rattimassiliensis, B.queenslandensis, B.elizabethae, B.phoceensis, B.coopersplainsensis, B.japonica and B.rochalimae. In our study, Bartonella species exhibited a strong association with their hosts. Zoonotic B.tribocorum, B.grahamii, B.elizabethae and B.rochalimae were found in synanthropic rodent species in southeastern China, which pose a potential threat to the public health. To prevent the spread of zoonotic Bartonella species to humans, preventive and control measures should be implemented, and more research is needed to confirm the pathogen's association with human disease.

Detection of antibodies against three zoonotic Bartonella spp. and cross-reactivity among species and Coxiella burnetii in dogs and cats from Central Thailand

Dogs and cats are important reservoir hosts of bacterial zoonotic pathogens, especially the Proteobacteria, Bartonella spp., and Coxiella burnetii. Bartonella spp. and C. burnetii are Gram-negative intracellular bacteria causing cat-scratch disease and query fever, respectively. Despite these two pathogens being dangerous, studies of their seroprevalence and cross-reactivity are limited in Thailand. The objectives of this study were to detect the seroprevalence of three zoonotic species of Bartonella and to evaluate cross-reactivity among Bartonella spp. and with C. burnetii. In total, 570 dog and cat serum samples were detected for antibodies against Bartonella spp. and C. burnetii using an indirect immunofluorescence antibody (IFA) test. At titer ≥ 1:64, tested serum that had a fluorescent intensity score ≥ 2 was interpreted as positive. Additionally, possible factors related to the seroprevalence were analyzed consisting of sex, breed, age, residing area, and ectoparasite control. Overall, the seroprevalence levels of Bartonella spp. and C. burnetii were 13.16% and 1.23%, respectively. All antigens of Bartonella were reacted to sera (1.23–7.72%), furthermore, both phases of C. burnetii were revealed in sera (0.35–1.05%). Interestingly, there was a poor agreement of cross-reactivity among Bartonella spp. at 5.56–8.70%, while cross-reactivity between Bartonella spp. and C. burnetii also showed poor agreement (2.80%). It is suggested that dogs and cats are important reservoirs of Bartonella spp., even in animals with ectoparasite control. The Bartonella seroprevalence was high in pure-breed animals with ectoparasite control, reflecting that Bartonella spp. infections can occur in owned, well-cared-for, and asymptomatic dogs and cats.

Molecular Detection of Bartonella Species in Rodents Residing in Urban and Suburban Areas of Central Thailand.

Bartonella spp. are Gram-negative zoonotic bacteria transmitted to humans via various blood-sucking arthropods. Rodents have been identified as reservoir hosts of several zoonotic pathogens, including Bartonella spp. In Thailand, studies of Bartonella spp. in rodents from urban areas are limited; thus, a study in this area is necessary. The objectives of this study were to detect Bartonella spp. in rodents in Thailand and to compare the species’ distribution across different areas. In total, 70 blood samples from rodents in urban and suburban areas were tested for Bartonella spp. using a conventional polymerase chain reaction that targeted the citrate synthase (gltA) gene. All Bartonella-positive sequences were analyzed using polymorphism in order to build a phylogenetic tree. Approximately 38% of the rodents studied contained Bartonella DNA. Both Rattus exulans (Pacific rat) and R. tanezumi (Asian house rat) contained Bartonella spp. Four species of Bartonella were detected in blood samples: B. tribocorum, B. phoceensis, B. grahamii, and B. rattimassiliensis. In addition, eight Pacific rats contained the B. kosoyi–B. tribocorum complex. Bartonella phoceensis and B. tribocorum–B. kosoyi complexes were found in a specific habitat (p < 0.05). Interestingly, only seven haplotypes were identified in the sequences analyzed, and only haplotype A was found in both rodent species. Finally, a monitoring program for zoonotic Bartonella infection, especially the B. kosoyi–B. tribocorum complex, B. phoceensis, B. grahamii, and B. rattimassiliensis should be established, especially in high-risk areas.

HEALTH RISKS THAT CAT SCRATCH DISEASE CREATES IN HUMANS, CONTROL AND TREATMENT CHOICES

It is concluded that animal health affects directly human health considering the fact that major part of diseases in humans result from animals. Bartonella agents are isolated from humans, rodents, rabbits, dogs, ruminants, wild and domestic cats. Bartonella infections are most commonly seen in domestic cats. Cats are considered primary mammalian reservoir in the transmission of zoonotic Bartonella (B.) henselae and B. clarridgeiae infections. Bartonella, vector-borne pathogen commonly appeared in our country and the world, can cause from mild flu signs to severe diseases such as endocarditis, myocarditis, arthritis, hepatitis in humans and animals. After Bartonella infections are transmitted by fleas to cats, cats may remain chronically infected with bacteria for months or years and especially they can transmit the infection to humans by bites or scratches. Cats infected by Bartonella spp. without any clinical signs can transmit the infection to humans. In the context of this review in the light of mentioned knowledge, data were presented for prevalence situations belonging to regions and countries that Bartonella infection commonly occurs in Turkey and the world. In addition, knowledge was given obtained from recent scientific sources for transmission ways of bartonellosis, clinical signs that it causes in humans and animals, diagnosis methods, treatment and control.

A multipronged next-generation sequencing metabarcoding approach unearths hyperdiverse and abundant dog pathogen communities in Cambodia.

Recent surveys in Southeast Asia, including Cambodia, have identified canine vector-borne pathogens (VBPs), including those with zoonotic potential, as highly prevalent. The lack of veterinary care alongside the close association semidomesticated dogs have with humans in the region exacerbates these zoonotic risks. Nonetheless, the number of studies investigating such pathogens and the threats they pose to dog and human health is limited. Here, we utilize a next-generation sequencing (NGS)-based metabarcoding protocol to conduct an assumption-free characterization of the bacterial, apicomplexan, and kinetoplastid blood-borne pathogens of free-roaming dogs from across Cambodia. From 467 dogs at five field sites, 62% were infected with one of eight confirmed pathogens, comprising Anaplasma platys (32%), Ehrlichia canis (20%), Hepatozoon canis (18%), Babesia vogeli (14%), Mycoplasma haemocanis (13%), the zoonotic pathogen Bartonella clarridgeiae (3%), Candidatus Mycoplasma haematoparvum (0.2%), and Trypanosoma evansi (0.2%). Coinfections of between two and four VBPs were common with 28% of dogs found to have a mixed infection. Moreover, DNA from putatively infectious agents belonging to the bacterial family and genera Coxiella, Mycobacterium, Neisseria, Rickettsiaceae, Treponema, and two uncharacterized Mycoplasma species were identified, in addition to protozoan genera Colpodella, Parabodo, and Bodo. Using a multiple logistic regression model, the presence of ectoparasites, abnormal mucous membranes, anemia, and total protein were found as predictors of canine VBP exposure. This study represents the first time an NGS metabarcoding technique has been used to holistically detect the bacterial and protozoan hemoparasites communities of dogs through an in-depth survey, highlighting the power of such methods to unearth a wide spectrum of pathogenic organisms in an unbiased manner.

Detection of zoonotic Bartonella species in ticks and fleas parasitizing free-ranging cats and dogs residing in temples of Bangkok, Thailand.

Bartonellosis is a vector-borne disease caused by intraerythrocytic bacteria known as Bartonella spp. The potential vectors that transmit Bartonella spp. are fleas, ticks, sand flies, and lice. Several Bartonella spp. cause diseases in humans; however, there is few molecular evidence of Bartonella spp. in vectors in Thailand. The objectives of this study were to investigate Bartonella spp. and to evaluate the spatial distribution of Bartonella spp. prevalence in the ectoparasites parasitizing free-ranging cats and dogs in temple clusters of Bangkok, Thailand. In total, 343 ectoparasites were studied to extract their genomic DNA. Species of all specimens were identified using an identification key and conventional polymerase chain reaction (cPCR) was applied to confirm flea and tick species. Extracted DNA samples were processed using primers that targeted the gltA, rpoB, ftsZ, and ribC genes of Bartonella spp. Then, PCR-positive amplicons were sequenced and a phylogenetic tree was constructed. Recorded data were statistically analyzed using descriptive statistics, the chi-square test, Fisher's exact test, and the odds ratio. Area data were analyzed and a prevalence distribution map was plotted. The major parasitizing ticks and fleas in this study were Rhipicephalus sanguineus and Ctenocephalides felis, respectively. Overall, the prevalence of Bartonella spp. in ectoparasites was 7.00%. The gltA amplicons revealed the presence of B. henselae (4.78%) and B. clarridgeiae (4.78%) in C. felis, and B. koehlerae (1.25%) and B. phoceensis (1.25%) in R. sanguineus. Bartonella DNA was encountered in 16/39 (41.03%) districts and 28.57% of the temple clusters. Bang Khun Thian district had the highest positive proportion and Bang Bon district showed co-evidence of different Bartonella species. In addition, the intervening zones were a risk factor of Bartonella (p<0.05), and the distribution map showed a scattered pattern of Bartonella-positive clusters. Finally, fleas showed to be important vector reservoirs for Bartonella spp., especially zoonotic species, however, experimental studies are needed to prove the Bartonella transmission in ticks.

Hedgehogs and Squirrels as Hosts of Zoonotic Bartonella Species.

Free-living animals frequently play a key role in the circulation of various zoonotic vector-borne pathogens. Bacteria of the genus Bartonella are transmitted by blood-feeding arthropods and infect a large range of mammals. Although only several species have been identified as causative agents of human disease, it has been proposed that any Bartonella species found in animals may be capable of infecting humans. Within a wide-ranging survey in various geographical regions of the Czech Republic, cadavers of accidentally killed synurbic mammalian species, namely Eurasian red squirrel (Sciurus vulgaris), European hedgehog (Erinaceus europaeus) and Northern white-breasted hedgehog (Erinaceus roumanicus), were sampled and tested for Bartonella presence using multiple PCR reaction approach targeting several DNA loci. We demonstrate that cadavers constitute an available and highly useful source of biological material for pathogen screening. High infection rates of Bartonella spp., ranging from 24% to 76%, were confirmed for all three tested mammalian species, and spleen, ear, lung and liver tissues were demonstrated as the most suitable for Bartonella DNA detection. The wide spectrum of Bartonella spp. that were identified includes three species with previously validated zoonotic potential, B. grahamii, B. melophagi and B. washoensis, accompanied by ‘Candidatus B. rudakovii’ and two putative novel species, Bartonella sp. ERIN and Bartonella sp. SCIER.

Zoonotic Bartonella species in Eurasian wolves and other free-ranging wild mammals from Italy.

Bartonellae are emerging vector‐borne pathogens infecting humans, domestic mammals and wildlife. Ninety‐seven red foxes (Vulpes vulpes), 8 European badgers (Meles meles), 6 Eurasian wolves (Canis lupus), 6 European hedgehogs (Erinaceus europaeus), 3 beech martens (Martes foina) and 2 roe deer (Capreolus capreolus) from Italian Nature Conservatory Parks were investigated for Bartonella infection. Several Bartonella species (9.84%; 95% CI: 4.55–15.12), including zoonotic ones, were molecularly detected among wolves (83.3%; 95% CI: 51–100.00), foxes (4.12%; 95% CI: 0.17–8.08), hedgehogs (33.33%; 95% CI: 0.00–71.05) and a roe deer. Bartonella rochalimae was the most common Bartonella species (i.e. in 4 foxes and 2 wolves) detected. Candidatus B. merieuxii and B. vinsonii subsp. berkhoffii were identified for the first time in wolves. Furthermore, Bartonella schoenbuchensis was identified in a roe deer and a new clone with phylogenetic proximity to B. clarridgeiae was detected in European hedgehogs. Zoonotic and other Bartonella species were significantly more frequent in Eurasian wolves (p < .0001), than in other free‐ranging wild mammals, representing a potential reservoir for infection in humans and domestic animals.

Exposure of Domestic Cats to Three Zoonotic Bartonella Species in the United States.

Cat-associated Bartonella species, which include B. henselae, B. koehlerae, and B. clarridgeiae, can cause mild to severe illness in humans. In the present study, we evaluated 1362 serum samples obtained from domestic cats across the U.S. for seroreactivity against three species and two strain types of Bartonella associated with cats (B. henselae type 1, B. henselae type 2, B. koehlerae, and B. clarridgeiae) using an indirect immunofluorescent assay (IFA). Overall, the seroprevalence at the cutoff titer level of ≥1:64 was 23.1%. Seroreactivity was 11.1% and 3.7% at the titer level cutoff of ≥1:128 and at the cutoff of ≥1:256, respectively. The highest observation of seroreactivity occurred in the East South-Central, South Atlantic, West North-Central, and West South-Central regions. The lowest seroreactivity was detected in the East North-Central, Middle Atlantic, Mountain, New England, and Pacific regions. We observed reactivity against all four Bartonella spp. antigens in samples from eight out of the nine U.S. geographic regions.

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.