Bartonella Genotypes Research Articles

Bartonella spp. in bats from the Brazilian Amazon Forest.

Despite the great diversity of bats (64 species) in the State of Acre, northwestern Brazil, there are no studies on occurrence and diversity of Bartonella spp. in bats in this region. The present study investigated the occurrence and molecular identity of Bartonella spp. in spleen samples (n = 271) from bats of 30 different species from this region, within the Amazon biome. Twenty-one out of 208 (10.1%) samples positive in the PCR for the mammalian gapdh endogenous genes were positive in the qPCR for Bartonella spp. based on the nuoG gene. The two gltA Bartonella genotypes detected grouped with those previously identified in bats from other locations, expanding the diversity of genotypes associated with bats. This study provided the first molecular evidence of the presence of Bartonella spp. in bats in the state of Acre and in bats of the species Lophostoma silvicolum, Vampyressa thyone, Tonatia saurophila and Phyllostomus elongatus.

Molecular detection of Bartonella spp. in bat-associated macronyssid mites (Acari: Macronyssidae) from Southern and Southeastern Brazil.

Despite the worldwide occurrence and high genetic diversity of Bartonella spp. in bats, few studies investigate their occurrence in bat-associated mites. To date, 26 species of Macronyssidae mite species have been reported from Brazil, and 15 of which were found parasitizing bats. The present study aimed to investigate the presence of Bartonella DNA in bat-associated macronyssid mites from Brazil. For this purpose, 393 macronyssid specimens were selected by convenience from the tissue bank of the Acari Collection of the Instituto Butantan (IBSP). These mites were collected from 14 different bat species in three different Brazilian States (Minas Gerais, Paraná, and Rio de Janeiro). Out of 165 mites positive in the PCR for the endogenous 18S rRNA gene, only eight were positive in the qPCR for Bartonella spp. based on the nuoG gene, and we were able to obtain two sequences base in this same gene, and one sequence based on the 16S rRNA gene. The phylogenetic inference based on the nuoG gene grouped the obtained sequences with Bartonella genotypes previously detected in bats and associated bat flies, while the phylogeny based on the 16S rRNA grouped the obtained sequence in the same clade of Bartonella genotypes previously detected in Dermanyssus gallinae. These findings suggest that macronyssid mites might be associated with the maintenance of bartonellae among bats.

Molecular detection and characterization of Bartonella spp. in small mammals in the Amazonia and Cerrado biomes, midwestern Brazil

Although Bartonella spp. have been worldwide described in rodents and bats, few studies have reported these agents in marsupials. The present work aimed to investigate the occurrence and genetic diversity of Bartonella in small mammals (rodents, marsupials, and bats) and associated ectoparasites in two ecoregions (Amazonia and Cerrado biomes) in midwestern Brazil. For this purpose, DNA samples from 378 specimens of small mammals (128 rodents, 111 marsupials, and 139 bats) and 41 fleas (Siphonaptera) were screened for the Bartonella genus employing a quantitative real-time PCR assay (qPCR) based on the nuoG (nicotinamide adenine dinucleotide dehydrogenase gamma subunit) gene. Then, positive samples in qPCR were submitted to conventional PCR (cPCR) assays targeting the gltA, ftsZ, and rpoB genes. One (0.78 %) rodent, 23 (16.54 %) bats, and 3 (7.31 %) fleas showed positive results in the qPCR for Bartonella sp. After cPCR amplification and sequencing, 13 partial Bartonella DNA sequences of the following genes were obtained only from bats´ blood samples: 9 gltA (citrate synthase), 3 ftsZ (cell division protein), and 1 rpoB (RNA polymerase beta subunit). The maximum likelihood inference based on the gltA gene positioned the obtained sequences in three different clades, closely related to Bartonella genotypes previously detected in other bat species and bat flies sampled in Brazil and other countries from Latin America. Similarly, the ftsZ sequences clustered in two different clades with sequences described in bats from Brazil, other countries from Latin America, and Georgia (eastern Europe). Finally, the Bartonella rpoB from a specimen of Lophostoma silvicolum clustered with a Bartonella sp. sequence obtained from a Noctilio albiventris (KP715475) from French Guiana. The present study provided valuable insights into the diversity of Bartonella genotypes infecting bats from two ecoregions (Amazonia and Cerrado) in midwestern Brazil and emphasized that further studies should be conducted regarding the description and evaluation of different lineages of Bartonella in wild small mammals and their ectoparasites in different Brazilian biomes.

Cattle Farming and Plantation Forest are Associated with Bartonella Occurrence in Wild Rodents.

Bartonella spp. are intracellular hemotropic bacteria primarily transmitted by arthropod vectors to various mammalian hosts, including humans. In this study, we conducted a survey on wild populations of sigmodontine rodents, Akodon azarae and Oxymycterus rufus, inhabiting the Paraná River delta region. The study involved eight grids organized in a crossed 2 × 2 design, where four of the grids were exposed to cattle while the other four were not, and four grids were located in implanted forest while the remaining four were in natural grasslands. Our objective was to examine whether the occurrence of Bartonella spp. in rodents was associated with silvopastoral activities (cattle raising associated with timber production) conducted in the region. Additionally, we evaluated the associations between Bartonella infection and other environmental and host factors. We present compelling evidence of a significant positive association between Bartonella prevalence and the presence of implanted forests and cattle. Furthermore, we identified the presence of a Bartonella genotype related to the pathogen Bartonella rochalimaea, infecting both A. azarae and Ox. rufus. These findings suggest that anthropogenic land-use changes, particularly the development of silvopastoral practices in the region, may disrupt the dynamics of Bartonella.

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.

Bats and their ectoparasites (Nycteribiidae and Spinturnicidae) carry diverse novel Bartonella genotypes, China.

Bartonella species are facultative intracellular bacteria and recognized worldwide as emerging zoonotic pathogens. Bartonella were isolated or identified by polymerase chain reaction (PCR) in bats and their ectoparasites worldwide, whereas the association between them was scarce, especially in Asia. In this study, a retrospective analysis with frozen samples was carried out to identify the genetic diversity of Bartonella in bats and their ectoparasites and to investigate the relationships of Bartonella carried by bats and their ectoparasites. Bats and their ectoparasites (bat flies and bat mites) were collected from caves in Hubei Province, Central China, from May 2018 to July 2020. Bartonella were screened by PCR amplification and sequencing of three genes (gltA, rpoB, and ftsZ). Bats, bat flies, and bat mites carried diverse novel Bartonella genotypes with a high prevalence. The sharing of some Bartonella genotypes between bats and bat flies or bat mites indicated a potential role of bat flies and bat mites as vectors of bartonellae, while the higher genetic diversity of Bartonella in bat flies than that in bats might be due to the vertical transmission of this bacterium in bat flies. Therefore, bat flies might also act as reservoirs of Bartonella. In addition, human‐pathogenic B. mayotimonesis was identified in both bats and their ectoparasites, which expanded our knowledge on the geographic distribution of this bacterium and suggested a potential bat origin with bat flies and bat mites playing important roles in the maintenance and transmission of Bartonella.

Intra- and Inter-Host Assessment of Bartonella Diversity with Focus on Non-Hematophagous Bats and Associated Ectoparasites from Brazil.

The relationship among bats, ectoparasites and associated microorganisms is important to investigate how humans can become exposed to zoonotic agents. Even though the diversity of Bartonella spp. in bats and ectoparasites has been previously reported, the occurrence of gltA genotypes within hosts has not been assessed so far. We aimed to investigate the genetic diversity of Bartonella spp. in non-hematophagous bats and associated ectoparasites by assessing cloned gltA Bartonella genotypes in intra- and inter-hosts levels, as well as by using three additional molecular markers. Overall, 13.5% (18/133) bat blood samples, 17.18% bat flies (11/64) and 23.8% (5/21) Macronyssidae mite pools showed to be positive for Bartonella spp. Seventeen positive samples were submitted to gltA-cloning and three clones were sequenced for each sample. We also obtained 11, seven and three sequences for nuoG, rpoB and ftsZ genes, respectively. None were positive for the other target genes. We found at least two genotypes among the three gltA-cloned sequences from each sample, and 13 between all the 51 sequences. Among the nuoG, rpoB and ftsZ sequences we found eight, five and three genotypes, respectively. In the phylogenetic analysis, the sequences were positioned mainly in groups related to Bartonella identified in rodents, bats and bat flies. Herein, we showed the genetic diversity of Bartonella in bat’s blood and associated ectoparasites samples at both intra- and inter-host levels.

Investigation of Bartonella spp. in brazilian mammals with emphasis on rodents and bats from the Atlantic Forest.

The Bartonella species are zoonotic agents that infect mammals and are transmitted by arthropod vectors. Approximately 18 distinct genotypes cause diseases in humans, and may be spread by both domestic and wild animals. In Brazil, Bartonella genotypes have been identified in several species of wild mammals, and in the present study, we analyzed samples from non-human primates (marmosets), marsupials, rodents, and bats, and compared them with the genotypes described in mammals from Brazil, to examine the distribution of Bartonella genotypes in two impacted areas of Rio de Janeiro state, in southeastern Brazil. We used polymerase chain reaction (PCR) methods to detect the Bartonella DNA using partial sequences of the gltA, ftsZ, and groEL genes. We generated Bayesian inference and maximum likelihood trees to characterize the positive PCR samples and infer the phylogenetic relationships of the genotypes. A total of 276 animals were captured, including 110 bats, 91 rodents, 38 marsupials, and 37 marmosets. The DNA of Bartonella was amplified from tissue samples collected from 12 (4.34%) of the animals, including eight rodents – Akodon cursor (5/44) and Nectomys squamipes (3/27) – and four bats, Artibeus lituratus (3/58) and Carollia perspicillata (1/15). We identified Bartonella genotypes closely related to those described in previous studies, as well as new genotypes in both the rodent and the bat samples. Considering the high diversity of the Bartonella genotypes and hosts identified in the present study, further research is needed to better understand the relationships between the different Bartonella genotypes and their vectors and host species. The presence of Bartonella in the wild rodents and bats from the study area indicates that the local human populations may be at risk of infection by Bartonella due to the spillover of these strains from the wild environment to domestic and peri-domestic environments.

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.

Occurrence of Bartonella genotypes in bats and associated Streblidae flies from Maranhão state, northeastern Brazil.

Bartonella is a genus of emerging zoonotic bacteria that are mainly associated with mammalian erythrocytes and endothelial cells. Bats are natural reservoirs for a variety of important pathogens that impact human and animal health. Recent reports have highlighted the role of bats and bat flies in the maintenance of Bartonella. Here, we showed that none of the 29 bat DNA blood samples obtained from five bat species in São Luís Island, state of Maranhão, northeastern Brazil, were positive for Bartonella in qPCR assays targeting nuoG. On the other hand, three out of 15 DNA samples (20%) from flies in the family Streblidae were positive for Bartonella. The BLASTn results showed that the gltA and rpoB sequences shared identities ranging from 97.2% to 100%, with Bartonella sequences amplified from bats or bat flies from Costa Rica and Brazil. These findings were supported by phylogenetic analyses based on Bayesian inferences. The present study showed that Bartonella genotypes are present in bat flies, thus shedding some light on the distribution of bat fly-related Bartonella genotypes in South America.

Molecular detection and genetic characterization of Bartonella species from rodents and their associated ectoparasites from northern Tanzania.

BackgroundBartonellae are intracellular bacteria, which can cause persistent bacteraemia in humans and a variety of animals. Several rodent-associated Bartonella species are human pathogens but data on their global distribution and epidemiology are limited. The aims of the study were to: 1) determine the prevalence of Bartonella infection in rodents and fleas; 2) identify risk factors for Bartonella infection in rodents; and 3) characterize the Bartonella genotypes present in these rodent and flea populations.Methods and resultsSpleen samples collected from 381 rodents representing six different species were tested for the presence of Bartonella DNA, which was detected in 57 individuals (15.0%; 95% CI 11.3–18.5), of three rodent species (Rattus rattus n = 54, Mastomys natalensis n = 2 and Paraxerus flavovottis n = 1) using a qPCR targeting the ssrA gene. Considering R. rattus individuals only, risk factor analysis indicated that Bartonella infection was more likely in reproductively mature as compared to immature individuals (OR = 3.42, p <0.001). Bartonella DNA was also detected in 53 of 193 Xenopsylla cheopis fleas (27.5%: 95% CI 21.3–34.3) collected from R.rattus individuals. Analysis of ssrA and gltA sequences from rodent spleens and ssrA sequences from fleas identified multiple genotypes closely related (≥ 97% similar) to several known or suspected zoonotic Bartonella species, including B. tribocorum, B. rochalimae, B. elizabethae and B. quintana.ConclusionsThe ssrA and gltA sequences obtained from rodent spleens and ssrA sequences obtained from fleas reveal the presence of a diverse set of Bartonella genotypes and increase our understanding of the bartonellae present in Tanzanian. Further studies are needed to fully characterise the prevalence, genotypes and diversity of Bartonella in different host populations and their potential impacts on human health.

Fleas of black rats (Rattus rattus) as reservoir host of Bartonella spp. in Chile.

BackgroundRattus rattus is a widely distributed, invasive species that presents an important role in disease transmission, either directly or through vector arthropods such as fleas. These black rats can transmit a wide variety of pathogens, including bacteria of the genus Bartonella, which can cause diseases in humans and animals. In Chile, no data are available identifying fleas from synanthropic rodents as Bartonella vectors. The aim of this study was to investigate the prevalence of Bartonella spp. in the fleas of R. rattus in areas with different climate conditions and featuring different human population densities.MethodsIn all, 174 fleas collected from 261 R. rattus captured from 30 localities with different human densities (cities, villages, and wild areas) across five hydrographic zones of Chile (hyper-arid, arid, semi-arid, sub-humid, and hyper-humid) were examined. Bartonella spp. presence was determined through polymerase chain reaction, using gltA and rpoB genes, which were concatenated to perform a similarity analysis with BLAST and phylogenetic analysis.ResultsOverall, 15 fleas species were identified; Bartonella gltA and rpoB fragments were detected in 21.2% (37/174) and 19.5% (34/174) of fleas, respectively. A total of 10 of the 15 fleas species found were positive for Bartonella DNA. Leptopsylla segnis was the most commonly collected flea species (n = 55), and it also presented a high prevalence of Bartonella DNA (P% = 34.5%). The highest numbers of fleas of this species were collected in villages of the arid zone. There were no seasonal differences in the prevalence of Bartonella DNA. The presence of Bartonella DNA in fleas was recorded in all hydrographic areas, and the arid zone presented the highest prevalence of this species. Regarding areas with different human densities, the highest prevalence was noted in the villages (34.8% gltA and 31.8% rpoB), followed by cities (14.8% gltA and 11.1% rpoB) and wild areas (7.4% gltA and 14.8% rpoB). The BLAST analysis showed a high similitude (>96%) with four uncharacterized Bartonella genotypes and with two species with zoonotic potential: B. mastomydis and B. tribocorum. The phylogenetic analysis showed a close relationship with B. elizabethae and B. tribocorum. This is the first study to provide evidence of the presence of Bartonella in fleas of R. rattus in Chile, indicating that the villages and arid zone correspond to areas with higher infection risk.

Genetic diversity of Bartonella spp. in vampire bats from Brazil.

Recently, an increasing number of Bartonella species have been emerged to cause human diseases. Among animal reservoirs for Bartonella spp., bats stand out due to their high mobility, wide distribution, social behaviour and long-life span. Although studies on the role of vampire bats in the epidemiology of rabies have been extensively investigated in Latin America, information on the circulation and genetic diversity of Bartonella species in these bat species is scarce. In the present work, 208 vampire bats, namely Desmodus rotundus (the common vampire bat; n=167), Diphylla ecaudata (the hairy-legged vampire bat; n=32) and Diaemus youngii (the white-winged vampire bat; n=9) from 15 different states in Brazil were sampled. DNA was extracted from liver tissue samples and submitted to real-time PCR (qPCR) and conventional PCR (cPCR) assays for Bartonella spp. targeting five genetic loci, followed by phylogenetic and genotype network analyses. Fifty-one out of 208 liver samples (24.51%) were positive for Bartonella DNA in the ITS real-time PCR assay [40 (78.43%) of them were from D.rotundus from 11 states, and 11 (21.57%) samples from D.ecaudata from three states. Eleven genotypes were found for each gltA and rpoB genes. Several ITS sequences detected in the present study clustered within the lineage that includes B.bacilliformis and B.ancachensis. The Bayesian phylogenetic inference based on the gltA gene positioned the obtained sequences in six different clades, closely related to Bartonella genotypes previously detected in D.rotundus and associated ectoparasites sampled in Latin America. On the other hand, the Bartonella rpoB genotypes clustered together with the ruminant species, B.schoenbuchensis and B.chomelii. The present study describes for the first time the molecular detection of Bartonella spp. in D.ecaudata bats. It also indicates that Bartonella spp. of vampire bats are genetically diverse and geographically widespread in Brazil.

Molecular detection of Bartonella in fleas (Hexapoda, Siphonaptera) collected from wild rodents (Cricetidae, Sigmodontinae) from Argentina.

Bartonella are facultative intracellular Gram-negative bacteria, transmitted mainly by hematophagous arthropods, and the rodents act as a natural reservoir. Different species of Bartonella associated with rodents have been implicated as causing human disease. Studies from Argentina are scarce and no Bartonella from fleas have been reported previously. The present study investigated the presence of Bartonella spp. in fleas associated with sigmodontine rodents in four localities of the Santa Cruz Province, Argentina. In total, 51 fleas (four species) were analysed of which 41.2% were found to be positive for the gltA gene fragment via a nested polymerase chain reaction. All positive fleas were of the species Neotyphloceras crackensis from three different localities. Eight of the 21 amplified samples were sequenced, and the presence of three different genotypes was detected with an identity of 95.5-98.8% amongst themselves. Bartonella genotypes from American rodents and rodent fleas were recovered in a monophyletic group. Similarly, most of the Peruvian and all Argentinean variants constitute a natural group sister of the American remainder. The importance of the Bartonella spp. with respect to public health is unknown, although future studies could provide evidence of the possible involvement of N. crackensis in the Bartonella transmission cycles.

Molecular detection of vector-borne bacteria in bat ticks (Acari: Ixodidae, Argasidae) from eight countries of the Old and New Worlds

BackgroundDespite the increasingly recognized eco-epidemiological significance of bats, data from molecular analyses of vector-borne bacteria in bat ectoparasites are lacking from several regions of the Old and New Worlds.MethodsDuring this study, six species of ticks (630 specimens) were collected from bats in Hungary, Romania, Italy, Kenya, South Africa, China, Vietnam and Mexico. DNA was extracted from these ticks and analyzed for vector-borne bacteria with real-time PCRs (screening), as well as conventional PCRs and sequencing (for pathogen identification), based on the amplification of various genetic markers.ResultsIn the screening assays, Rickettsia DNA was only detected in bat soft ticks, whereas Anaplasma phagocytophilum and haemoplasma DNA were present exclusively in hard ticks. Bartonella DNA was significantly more frequently amplified from hard ticks than from soft ticks of bats. In addition to Rickettsia helvetica detected by a species-specific PCR, sequencing identified four Rickettsia species in soft ticks, including a Rickettsia africae-like genotype (in association with a bat species, which is not known to migrate to Africa), three haemotropic Mycoplasma genotypes in Ixodes simplex, and Bartonella genotypes in I. ariadnae and I. vespertilionis.ConclusionsRickettsiae (from both the spotted fever and the R. felis groups) appear to be associated with soft rather than hard ticks of bats, as opposed to bartonellae. Two tick-borne zoonotic pathogens (R. helvetica and A. phagocytophilum) have been detected for the first time in bat ticks. The present findings add Asia (China) to the geographical range of R. lusitaniae, as well as indicate the occurrence of R. hoogstraalii in South Africa. This is also the first molecular evidence for the autochthonous occurrence of a R. africae-like genotype in Europe. Bat haemoplasmas, which are closely related to haemoplasmas previously identified in bats in Spain and to “Candidatus Mycoplasma haemohominis”, are reported here for the first time from Central Europe and from any bat tick.

Untangling the knots: Co-infection and diversity of Bartonella from wild gerbils and their associated fleas.

Based on molecular data, previous studies have suggested a high overall diversity and co-infection rates of Bartonella bacteria in wild rodents and their fleas. However, partial genetic characterization of uncultured co-infecting bacteria limited sound conclusions concerning intra- and inter-specific diversity of the circulating Bartonella. To overcome this limitation, Bartonella infections of wild populations of two sympatric gerbil species and their fleas were explored by multiple isolations of Bartonella organisms. Accordingly, 448 pure Bartonella isolates, obtained from 20 rodent blood and 39 flea samples, were genetically characterized to the genotype and species levels. Results revealed a remarkable diversity and co-infection rates of Bartonella among these sympatric rodents and their associated fleas. Specifically, 38 genotypes, classified into four main Bartonella species, were identified. Co-infection was confirmed in 56% of the samples, which contained two to four Bartonella genotypes per sample, belonging to up to three different species. Recombination within and between these species was demonstrated, serving as a direct evidence of the frequent bacteria-bacteria interactions. Moreover, despite the noticeable interchange of common Bartonella genotypes between rodents and fleas, the co-occurrence of genotypes was not random and differences in the overall diversity, and the ecological and phylogenetic similarities of the infection compositions were significantly associated with the carrier type (rodent vs. flea) and the rodent species. Thus, comprehensive identification of the co-infecting organisms enabled the elucidation of ecological factors affecting the Bartonella distribution among reservoirs and vectors. This study may serve as a model for the investigation of other vector-borne organisms and their relationships with Bartonella.

Global fingerprint of humans on the distribution of Bartonella bacteria in mammals.

As humans move and alter habitats, they change the disease risk for themselves, their commensal animals and wildlife. Bartonella bacteria are prevalent in mammals and cause numerous human infections. Understanding how this genus has evolved and switched hosts in the past can reveal how current patterns were established and identify potential mechanisms for future cross-species transmission. We analyzed patterns of Bartonella transmission and likely sources of spillover using the largest collection of Bartonella gltA genotypes assembled, including 67 new genotypes. This pathogenic genus likely originated as an environmental bacterium and insect commensal before infecting mammals. Rodents and domestic animals serve as the reservoirs or at least key proximate host for most Bartonella genotypes in humans. We also find evidence of exchange of Bartonella between phylogenetically distant domestic animals and wildlife, likely due to increased contact. Care should be taken to avoid contact between humans, domestic animals and wildlife to protect the health of all.

Molecular detection of Bartonella spp. and Rickettsia spp. in bat ectoparasites in Brazil.

The family Streblidae comprises a monophyletic group of Hippoboscoidea, hematophagous dipterans that parasitize bats. Bartonella spp. and Rickettsia spp. have been reported in bats sampled in Europe, Africa, Asia, North, Central and South America. However, there are few reports on the Bartonella and Rickettsia bacteria infecting Hippoboscoidea flies and mites. While Spinturnicidae mites are ectoparasites found only in bats, those belonging to the family Macronyssidae comprise mites that also parasitize other mammal species. This study investigates the occurrence and assesses the phylogenetic positioning of Bartonella spp. and Rickettsia spp. found in Streblidae flies and Spinturnicidae and Macronyssidae mites collected from bats captured in Brazil. From May 2011 to April 2012 and September 2013 to December 2014, 400 Streblidae flies, 100 Macronyssidaes, and 100 Spinturnicidae mites were collected from bats captured in two sites in northeastern Nova Iguaçu, Rio de Janeiro, southeastern Brazil. Forty (19.8%) out of 202 Streblidae flies were positive for Bartonella spp. in qPCR assays based on the nuoG gene. Among the flies positive for the bacterium, six (18%) were Paratrichobius longicrus, seven (29%) Strebla guajiro, two (40%) Aspidoptera phyllostomatis, five (11%) Aspidoptera falcata, one (10%) Trichobius anducei, one (25%) Megistopoda aranea, and 18 (32%) Trichobius joblingi, and collected from bats of the following species: Artibeus lituratus, Carollia perspicillata, Artibeus planirostris, Sturnira lilium, and Artibeus obscurus. Six sequences were obtained for Bartonella (nuoG [n = 2], gltA [n = 2], rpoB [n = 1], ribC = 1]). The phylogenetic analysis based on gltA (750pb) gene showed that the Bartonella sequences clustered with Bartonella genotypes detected in bats and ectoparasites previously sampled in Latin America, including Brazil. Only one sample (0.49%) of the species Trichobius joblingi collected from a specimen of Carollia perspicillata was positive for Rickettsia sp. in cPCR based on the gltA gene (401bp). This sequence was clustered with a ‘Candidatus Rickettsia andaenae" genotype detected in an Amblyomma parvum tick collected from a rodent in the southern region of Brazilian Pantanal. The sampled Macronyssidae and Spinturnicidae mites were negative for Bartonella spp. and Rickettsia spp. This study demonstrated the first occurrence of Bartonella spp. and Rickettsia spp. DNA in Streblidae flies collected from bats in Brazil.

Eco-epidemiology of Novel Bartonella Genotypes from Parasitic Flies of Insectivorous Bats.

Bats are important zoonotic reservoirs for many pathogens worldwide. Although their highly specialized ectoparasites, bat flies (Diptera: Hippoboscoidea), can transmit Bartonella bacteria including human pathogens, their eco-epidemiology is unexplored. Here, we analyzed the prevalence and diversity of Bartonella strains sampled from 10 bat fly species from 14 European bat species. We found high prevalence of Bartonella spp. in most bat fly species with wide geographical distribution. Bat species explained most of the variance in Bartonella distribution with the highest prevalence of infected flies recorded in species living in dense groups exclusively in caves. Bat gender but not bat fly gender was also an important factor with the more mobile male bats giving more opportunity for the ectoparasites to access several host individuals. We detected high diversity of Bartonella strains (18 sequences, 7 genotypes, in 9 bat fly species) comparable with tropical assemblages of bat-bat fly association. Most genotypes are novel (15 out of 18 recorded strains have a similarity of 92-99%, with three sequences having 100% similarity to Bartonella spp. sequences deposited in GenBank) with currently unknown pathogenicity; however, 4 of these sequences are similar (up to 92% sequence similarity) to Bartonella spp. with known zoonotic potential. The high prevalence and diversity of Bartonella spp. suggests a long shared evolution of these bacteria with bat flies and bats providing excellent study targets for the eco-epidemiology of host-vector-pathogen cycles.

Genetic Diversity of Bartonella spp. in Wild Mammals and Ectoparasites in Brazilian Pantanal.

The present work aimed to investigate the genetic diversity of Bartonella in mammals and ectoparasites in Pantanal wetland, Brazil. For this purpose, 31 Nasua nasua, 78 Cerdocyon thous, 7 Leopardus pardalis, 110 wild rodents, 30 marsupials, and 42 dogs were sampled. DNA samples were submitted to a quantitative real-time PCR assay (qPCR). Positive samples in qPCR were submitted to conventional PCR assays targeting other five protein-coding genes. Thirty-five wild rodents and three Polygenis (P.) bohlsi bohlsi flea pools showed positive results in qPCR for Bartonella spp. Thirty-seven out of 38 positive samples in qPCR were also positive in cPCR assays based on ftsZ gene, nine in nuoG-cPCR, and six in gltA-cPCR. Concatenated phylogenetic analyses showed that two main genotypes circulate in rodents and ectoparasites in the studied region. While one of them was closely related to Bartonella spp. previously detected in Cricetidae rodents from North America and Brazil, the other one was related to Bartonella alsatica, Bartonella pachyuromydis, Bartonella birtlesii, Bartonella acomydis, Bartonella silvatica, and Bartonella callosciuri. These results showed that at least two Bartonella genotypes circulate among wild rodents. Additionally, the present study suggests that Polygenis (P.) bohlsi bohlsi fleas could act as possible Bartonella vectors among rodents in Pantanal wetland, Brazil.