Association of Bartonella Species with Wild and Synanthropic Rodents in Different Brazilian Biomes

Molecular surveillance of zoonotic pathogens from wild rodents in the Republic of Korea

BACKGROUND

Rodents are recognized as major reservoirs of numerous zoonotic pathogens and are involved in the transmission and maintenance of infectious diseases. Furthermore, despite their importance, diseases transmitted by rodents have been neglected. To date, there have been limited epidemiological studies on rodents, and information regarding their involvement in infectious diseases in the Republic of Korea (ROK) is still scarce.

METHODOLOGY/PRINCIPAL FINDINGS

We investigated rodent-borne pathogens using nested PCR/RT-PCR from 156 rodents including 151 Apodemus agrarius and 5 Rattus norvegicus from 27 regions in eight provinces across the ROK between March 2019 and November 2020. Spleen, kidney, and blood samples were used to detect Anaplasma phagocytophilum, Bartonella spp., Borrelia burgdorferi sensu lato group, Coxiella burnetii, Leptospira interrogans, and severe fever with thrombocytopenia syndrome virus (SFTSV). Of the 156 rodents, 73 (46.8%) were infected with Bartonella spp., 25 (16.0%) with C. burnetii, 24 (15.4%) with L. interrogans, 21 (13.5%) with A. phagocytophilum, 9 (5.8%) with SFTSV, and 5 (3.2%) with Borrelia afzelii. Co-infections with two and three pathogens were detected in 33 (21.1%) and 11 rodents (7.1%), respectively. A. phagocytophilum was detected in all regions, showing a widespread occurrence in the ROK. The infection rates of Bartonella spp. were 83.3% for B. grahamii and 16.7% for B. taylorii.

CONCLUSIONS/SIGNIFICANCE

To the best of our knowledge, this is the first report of C. burnetii and SFTSV infections in rodents in the ROK. This study also provides the first description of various rodent-borne pathogens through an extensive epidemiological survey in the ROK. These results suggest that rodents harbor various pathogens that pose a potential threat to public health in the ROK. Our findings provide useful information on the occurrence and distribution of zoonotic pathogens disseminated among rodents and emphasize the urgent need for rapid diagnosis, prevention, and control strategies for these zoonotic diseases.

Molecular evidence of Bartonella spp. in tropical wild birds from the Brazilian Pantanal, the largest wetland in South America

Despite the worldwide occurrence of bartonellae in a broad range of mammal species, in which they usually cause a long-lasting erythrocytic bacteremia, few studies reported Bartonella spp. in avian hosts. The present work aimed to investigate the occurrence and molecular identity of Bartonella spp. infecting birds in the Pantanal wetland, central-western Brazil using a multigene approach. For this purpose, blood samples were collected from 517 individuals from 13 avian orders in the states of Mato Grosso and Mato Groso do Sul. DNA was extracted from avian blood and 500/517 (96.7%) samples were positive in a conventional PCR targeting the avian β-actin gene. Nineteen (3.8%) out of 500 avian blood samples were positive in a qPCR assay for Bartonella spp. based on the nuoG gene. Among 19 avian blood DNA samples positive in the qPCR for Bartonella spp., 12 were also positive in the qPCR for Bartonella based on the 16S-23S RNA Intergenic region (ITS). In the PCR assays performed for molecular characterization, one 16S rRNA, three ribC, and one nuoG sequences were obtained. Based on BLASTn results, while 1 nuoG, 2 ribC, and 2 ITS sequences showed high identity to Bartonella henselae, one 16S rRNA and 2 ITS showed high similarity to Bartonella machadoae in the sampled birds. Bartonella spp. related to B. henselae and B. machadoae were detected, for the first time, in wild birds from the Brazilian Pantanal.

Fleas (Siphonaptera, Latreille, 1825) from Rio Grande do Sul State, Brazil: Species Diversity, Hosts, and One Health Approach

Background: Fleas are ectoparasitic insects with holometabolous development. It has a hematophagous habit with mouthparts adapted to sting and suck its hosts. There are about 3000 species in the world, ∼61 in Brazil, and 19 in Rio Grande do Sul state. The objective of the research is to catalog the diversity of fleas recorded in the state, their respective hosts, and endosymbionts. Materials and Methods: To this end, a search was carried out in the scientific literature, from articles, books, to abstracts submitted to congresses. Results: The 19 species of fleas occurring in Rio Grande do Sul are divided into 7 families and 10 genera. These ectoparasites, in addition to being found in the environment, were associated with 10 different families of hosts in Rio Grande do Sul, and on the endosymbiont, agents found associated with fleas, there were 7 different species. The main agents researched in the state are Rickettsia spp. and Bartonella spp. The relationships between parasites, hosts, environment, and etiological agents present different scenarios, whether anthropized or conserved, but unknown. Sometimes, this overlap, a factor that aggravates the possibility of spillovers, either from cosmopolitan fleas in these conserved areas, or from their endosymbionts. Conclusion: Thus, it is important to characterize the environment so that the complexities of each location are known for the adoption of environmental and public health policies in each case. The challenges are extensive, but necessary in view of the One Health perspective.

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.

Bartonella in Norway rats (Rattus norvegicus) from the urban slum environment in Brazil

Bartonella are rodent-borne bacteria that cause varied human etiologies. Studies on synanthropic rodents are rare, causing gaps in epidemiological knowledge. We tested bloodclot samples from 79 rats from an urban slum in Salvador, Brazil through PCR targeting gltA gene. Nine samples (11.4%) were positive: six had 100% identity with Bartonella sp. isolate JF429580 and 99.5% with B. queenslandensis strain AUST/NH8; three were 100% identical to isolate JF429532 and 99.7% to B. tribocorum. This is the second report on urban rat Bartonella indicating bacterial circulation at detectable rates. Its presence in rats from vulnerable human settlements demands public health attention.

Molecular evidence of Bartonella spp. in wild lowland tapirs (Tapirus terrestris), the largest land mammals in Brazil

The genus Bartonella (Hyphomicrobiales: Bartonellaceae) encompasses facultative intracellular α-proteobacteria that parasite erythrocytes and endothelial cells from a wide range of vertebrate hosts and can cause disease in animals and humans. Considering the large diversity of vertebrate species that may act as reservoirs and arthropod species that may be associated with Bartonella transmission, the exposure of animals and humans to these microorganisms is likely underestimated. The present study aimed to investigate the occurrence of Bartonella sp. in wild tapirs (Tapirus terrestris; Perissodactyla: Tapiridae) from two biomes in Brazil: Pantanal and Cerrado. Ninety-nine GPS-monitored wild tapirs were sampled in Pantanal (n = 61/99) and Cerrado (n = 38/99). A qPCR (quantitative real-time polymerase chain reaction) assay targeting the nuoG gene was used for the screening for Bartonella spp. DNA. Positive samples were additionally subjected to conventional PCR assays targeting five molecular markers (ribC, gltA, rpoB, groEL, ITS). Eight (8/99; 08,08%) animals were positive in the qPCR assay for Bartonella spp.: 7 from Cerrado (7/8; 87.5%) and 1 from Pantanal (1/8; 12.5%). The 5 Bartonella ribC sequences obtained from tapirs' blood samples grouped together with Bartonella henselae obtained from cats, humans, wild felids and Ctenocephalides felis (Siphonaptera: Pulicidae) fleas. To the best of author's knowledge, this is the first report of Bartonella sp. in Tapirus terrestris. This finding contributes to the understanding of the occurrence of B henselae in wild mammals from Brazil as well as expands the knowledge regarding the potential vector-borne pathogens that may affect wild tapis from Cerrado and Pantanal biomes.

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.

Molecular epidemiology of Bartonella species from sympatric mammals collected in urban and rural areas of Punjab, Pakistan

Bartonella can infect a variety of mammals including humans and has been detected in the Americas, Europe, Africa, and Asia. Roughly two-thirds of identified Bartonella species are found and maintained in rodent reservoirs, with some of these species linked to human infections. Rodents (N=236) were caught from the Sahiwal division of Punjab, Pakistan and tested for Bartonella using PCR targeting gltA and rpoB genes, followed by sequencing of rpoB-positive samples. Genetic relatedness to other published Bartonella spp. rpoB gene sequences were examined using BLAST and phylogenetic analysis. Overall, 7.62% (18/236) of rodents were positive for both gltA and rpoB fragments. Rattus rattus and R. norvegicus had 7.94% (12/151) and 7.05% (6/85) positivity rates for Bartonella DNA, respectively. Phylogenetic analysis revealed a close relatedness between Bartonella spp. from Pakistan to Bartonella spp. from China, Nepal, and Malaysia. This study is the first reported detection of Bartonella spp. in R. rattus and R. norvegicus from the Sahiwal area of Punjab, Pakistan.

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.

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 machadoae sp. nov. isolated from wild rodents in the Pantanal wetland

It has been estimated that 75% of emerging infectious diseases comprise zoonoses, whose majority have free-living animals as reservoirs and are mainly transmitted by arthropod vectors. Although rodents represent important Bartonella reservoirs, there are few studies on the genotypic characterization of Bartonella species commonly found in this taxon and from different Brazilian biomes. Therefore, the present study aimed to investigate the occurrence, isolate and molecularly, morphologically and phenotypically characterize a new Bartonella species infecting free-living rodents sampled in the Brazilian Pantanal, the largest wetland in South America. For this purpose, 129 free-living rodents (79 Thrichomys fosteri, 4 Clyomys laticeps, and Oecomys mamorae) were captured. While blood samples were collected from 57 T. fosteri, 4 C. laticeps and 32 O. mamorae; spleen samples were collected from 22 T. fosteri and 14 O. mamorae. Blood and spleen samples were submitted to a qPCR for Bartonella spp. targeting the nuoG gene, using DNA samples extracted directly from blood/spleen, after passage in pre-enrichment liquid culture, and from colonies obtained from solid culture on chocolate agar. Combining all techniques, occurrence of 24.8% for Bartonella sp. was found among the sampled rodents. One Bartonella isolate (strain 56A) obtained from a T. fosteri's blood sample was closely related to the Bartonella vinsonii complex and selected for Whole Genome Sequencing (WGS) hybrid approach using Illumina NovaSeq and Nanopore sequencing platforms. This strain exhibits a circular 2.7 Mbp genome with an average C+G content of 39% and encoding to 2239 genes. In the phylogenomics based on 291 shared protein-coding genes, this strain was positioned in a unique clade, closely related to Bartonella vinsonii subsp. vinsonii, B. vinsonii subsp. berkhoffii and B. visonii subsp. arupensis. An Average Nucleotide Identity of 85% was found between the obtained isolate and Bartonella species belonging to B. vinsonii complex. These findings supported the separation of this strain, now formally named as Bartonella machadoae sp. nov., from the Bartonella vinsonii complex. In addition, Bartonella machadoae sp. nov. was characterized by capnophilic, microaerophilic and aerobic small rods with absence of pili and flagella. Phylogenetic and distance analyses based on five concatenated molecular markers suggest that Bartonella machadoae may parasite rodents from different Brazilian biomes. In conclusion, we described biochemical, phenotypic and genomic characteristics of Bartonella machadoae nov. sp. isolated from blood samples of T. fosteri rodents from the Brazilian Pantanal.

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.

Molecular identification and genetic diversity of Bartonella spp. in 24 bat species from Thailand

The study of bacterial zoonoses has been under-pursued despite the fact that bacteria cause the majority of zoonotic diseases, of which 70% have a wildlife origin. More Bartonella species are being identified as the cause of human diseases, and several of them have been linked to domestic and wild animals. Bats are outstanding reservoirs for Bartonella species because of their wide distribution, mobility, roosting behaviour, and long life span. Here, we carried out a PCR-based survey on bats that were collected from 19 sampling sites in eight provinces of Thailand from February 2018 to April 2021. Bartonella infection was investigated in a total of 459 bats that belong to 24 different bat species (21 species of which had never been previously studied in Thailand). PCR diagnostics revealed that 115 out of 459 (25.5%) blood samples tested positive for Bartonella. The nucleotide identities of the Bartonella 16S rRNA sequences in this study were between 95.78-99.66% identical to those of known zoonotic species (Bartonella ancashensis, Bartonella henselae, Bartonella bacilliformis and Bartonella australis) as well as to an unidentified Bartonella spp. In addition, the citrate synthase (gltA) and RNA polymerase-beta subunit (rpoB) genes of Bartonella were sequenced and analyzed in positive samples. The gltA and rpoB gene sequences from Hipposideros gentilis and Rhinolophus coelophyllus bat samples showed low nucleotide identity (<95%) compared to those of the currently deposited sequences in the GenBank database, indicating the possibility of new Bartonella species. The phylogenetic inference and genetic diversity were generated and indicated a close relationship with other Bartonella species previously discovered in Asian bats. Overall, the current study demonstrates the primary evidence pointing to a potential novel Bartonella species in bats. This discovery also contributes to our current understanding of the geographical distribution, genetic diversity, and host ranges of bat-related Bartonella.

Biomolecular Investigation of Bartonella spp. in Wild Rodents of Two Swiss Regions

Rodents represent a natural reservoir of several Bartonella species, including zoonotic ones. In this study, small wild rodents, collected from two sites in rural areas of Switzerland, were screened for Bartonella spp. using molecular detection methods. In brief, 346 rodents were trapped in two rural sites in the Gantrisch Nature Park of Switzerland (Plasselb, canton of Fribourg, and Riggisberg, canton of Bern). Pools of DNA originating from three animals were tested through a qPCR screening and an end-point PCR, amplifying the 16S-23S rRNA gene intergenic transcribed spacer region and citrate synthase (gltA) loci, respectively. Subsequently, DNA was extracted from spleen samples belonging to single animals of gltA positive pools, and gltA and RNA polymerase subunit beta (rpoB) were detected by end-point PCR. Based on PCR results and sequencing, the prevalence of infection with Bartonella spp. in captured rodents, was 21.10% (73/346): 31.78% in Apodemus sp. (41/129), 10.47% in Arvicola scherman (9/86), 17.05% in Myodes glareolus (22/129), and 50% in Microtus agrestis (1/2). A significant association was observed between Bartonella spp. infection and rodent species (p < 0.01) and between trapping regions and positivity to Bartonella spp. infection (p < 0.001). Similarly, prevalence of Bartonella DNA was higher (p < 0.001) in rodents trapped in woodland areas (66/257, 25.68%) compared to those captured in open fields (9/89, 10.11%). Sequencing and phylogenetic analysis demonstrated that the extracted Bartonella DNA belonged mainly to B. taylorii and also to Candidatus “Bartonella rudakovii”, B. grahamii, B. doshiae, and B. birtlesii. In conclusion, the present study could rise public health issues regarding Bartonella infection in rodents in Switzerland.

Molecular Survey and Genetic Diversity of Bartonella spp. in Small Indian Mongooses (Urva auropunctata) and Their Fleas on Saint Kitts, West Indies

This study aimed to molecularly survey and evaluate the genetic diversity of Bartonella spp. in mongooses and their fleas from St. Kitts. Spleen (n = 54), blood (n = 71), and pooled flea samples, all identified as Ctenocephalides felis (n = 53), were submitted to TaqMan real-time quantitative PCR (qPCR) targeting Bartonella-nuoG fragment (84 bp). Positive samples underwent further conventional PCR assays targeting five loci (gltA, rpoB, fstZ, nuoG, and ITS), subsequent sequencing, and phylogenetic and haplotype analyses. The overall occurrence of Bartonella spp. in mongooses and fleas was 51.2% (64/125 [95% CI (42.1–60.2%)]) and 62.3% (33/53) [95% CI (47.9–75.2%)]), respectively. From samples sequenced across the five loci, 50.8% (33/65) were identified as Bartonella henselae, 26.2% (17/65) were 96.74–99.01% similar by BLAST analysis to an unidentified Bartonella sp. previously reported in Japanese badgers (Meles anakuma), and 23.1% (15/65) were co-infected with both species. Nucleotide polymorphism analysis showed low diversity amongst haplotypes but did concur with phylogenetic analysis, placing the unidentified species in a separate clade from B. henselae by multiple mutational events. Our data confirms that mongooses and Ctenocephalides felis fleas collected from them are not only potential reservoirs for B. henselae but also a novel Bartonella sp. which we propose be called ‘Candidatus Bartonella kittensis’.

Rodent-Related Zoonotic Pathogens at the Human-Animal-Environment Interface in Qatar: A Systematic Review and Meta-Analysis

Rodents are one of the most diversified terrestrial mammals, and they perform several beneficial activities in nature. These animals are also important as carriers of many pathogens with public health importance. The current systematic review was conducted to formulate a true depiction of rodent-related zoonoses in Qatar. Following systematic searches on PubMed, Scopus, Science Direct, and Web of Science and a screening process, a total of 94 published articles were selected and studied. The studied articles reported 23 rodent-related zoonotic pathogens that include nine bacterial, eleven parasitic, and three viral pathogens, from which the frequently reported pathogens were Mycobacterium tuberculosis (32 reports), Escherichia coli (23), and Salmonella spp. (16). The possible pathway of entry of the rodent-borne pathogens can be the land port, seaports, and airport of Qatar through carrier humans and animals, contaminated food, and agricultural products. The pathogens can be conserved internally by rodents, pets, and livestock; by agricultural production systems; and by food marketing chains. The overall estimated pooled prevalence of the pathogens among the human population was 4.27% (95%CI: 4.03–4.51%; p < 0.001) with significant heterogeneity (I² = 99.50%). The top three highest prevalent pathogens were M.tuberculosis (30.90%; 22.75–39.04%; p < 0.001; I² = 99.70%) followed by Toxoplasma gondii (21.93%; 6.23–37.61%; p < 0.001; I² = 99.30%) and hepatitis E virus (18.29%; 11.72–24.86%; p < 0.001; I² = 96.70%). However, there is a knowledge gap about the listed pathogens regarding the occurrence, transmission pathways, and rodent role in transmission dynamics at the human–animal–environment interface in Qatar. Further studies are required to explore the role of rodents in spreading zoonotic pathogens through the One Health framework, consisting of zoologists, ecologists, microbiologists, entomologists, veterinarians, and public health experts in this country.

Testis structure, duration of spermatogenesis and daily sperm production in four wild cricetid rodent species (A. cursor, A. montensis, N. lasiurus, and O. nigripes)

Although rodents represent approximately 40% of all living mammalian species, our knowledge regarding their reproductive biology is still scarce. Due to their high vulnerability to environmental changes, wild rodents have become beneficial models for ecological studies. Thus, we aimed to comparatively investigate key functional testis parameters in four sexually mature wild rodent species (A. cursor, A. montensis, N. lasiurus, and O. nigripes). These species belong to the Cricetidae family, which is the most diverse family of rodents in South America, with a total of ~120 species in Brazil. The results found for the gonadosomatic index and the sickled sperm head shape observed strongly suggest that the species here evaluated are promiscuous, prolific, and short-lived. The duration of spermatogenesis was relatively short and varied from ~35-40 days. Both the percentage of seminiferous tubules (ST) in the testis parenchyma (~95-97%) and the number of Sertoli cells (SC) (~48-70 million) per testis gram were very high, whereas a fairly good SC efficiency (~8-13 round spermatids per SC) was observed. In comparison to other mammalian species studied, particularly the rodents of the suborder Myomorpha (i.e. hamsters, rats and mice), the rodents herein investigated exhibited very high (~62-80 million) daily sperm production per testis gram. This impressive spermatogenic efficiency resulted mainly from the short duration of spermatogenesis and quite high values found for the ST percentage in the testis and the SC number per testis gram. We expect that the knowledge here obtained will help conservation programs and the proper management of wildlife.

Genetic characterizations of Toll-like receptors in the brown rat and their associations with pathogen infections

Toll-like receptors (TLRs) are important initiators of innate immune responses that target host-pathogen interactions. However, further research into the molecular characteristics of TLRs in wild populations is required, as well as how TLRs genetically influenced pathogen infections in the brown rat (Rattus norvegicus). Here, we explored the genetic characterization and evolution of 2 sensing nucleic acid TLRs (TLR7 and TLR8) and 2 sensing non-nucleic acid TLRs (TLR2 and TLR4) in the wild brown rat, and assessed their associations with 2 RNA viruses (Seoul hantavirus and rat hepatitis E virus (HEV)) and 2 bacteria (Leptospira and Bartonella). In these 4 TLRs, we discovered a total of 16 variants. Furthermore, TLR8 had high genetic diversity among 7 variants, while TLR2 had low genetic diversity with only 1 variant. According to selective pressure analyses, TLR4, TLR7, and TLR8 genes evolved under purifying selection. Interestingly, significant associations were found between 3 TLR8 variants and HEV infection, as well as 1 TLR2 variant and Bartonella infection. Overall, our findings provided a glimpse into the genetic characterization of TLRs in the brown rat, and further demonstrated that TLR2 and TLR8 genetic variations were related to Bartonella and HEV infection, respectively. Especially, TLR8 may be a good candidate immune gene for future research on molecular ecology and functional adaptation in wild populations.

Relationships between vector-borne parasites and free-living mammals at the Brazilian Pantanal

In nature, parasitic infections must be addressed as complex systems involving parasite-host relationships on a temporal and spatial scale. Since the parasites cover a great biological diversity, we can expect that wildlife are exposed simultaneously to different parasites. In this sense, the objective of this work was to determine the relationships between free-living mammals and their associated hemoparasites in the Brazilian Pantanal. We used the data published during 2017 and 2018 by de Sousa et al. regarding the detection of vector-borne pathogens (VBP), namely Anaplasma, Babesia, Bartonella, Cytauxzoon, Ehrlichia, Hepatozoon, Mycoplasma, and Theileria, in nine species of free-living mammals belonging to orders Carnivora, Rodentia, and Didelphimorphia. We assume as infected an individual positive on any of parasitological, molecular, and/or serological tests. We observed a strong association between the wild felid Leopardus pardalis with Cytauxzoon, the wild canid Cerdocyon thous with Hepatozoon, the small rodent Thrichomys fosteri with Bartonella, and the procyonid Nasua nasua with Mycoplasma and Theileria. Therefore, N. nasua, C. thous, T. fosteri, and the small rodent Oecomys mamorae can be considered key species for the maintenance of selected VBP in the Pantanal region, because they showed a high number of single and coinfections. Together, our results highlighted the importance of coinfection as a common phenomenon in nature.

Detection of Bartonella sp. and a novel spotted fever group Rickettsia sp. in Neotropical fleas of wild rodents (Cricetidae) from Southern Brazil

The Neotropical region shows a great diversity of fleas, comprising more than 50 genera. The importance of the study of fleas is linked to their potential role as disease vectors. The aim of this study is to investigate the presence of Rickettsia spp. and Bartonella spp. in Neotropical fleas collected from wild rodents in Southern Brazil. From 350 rodents captured, 30 were parasitized by fleas. A total of 61 fleas belonging to two genera and six different species were collected (Craneopsylla minerva minerva, Polygenis occidentalis occidentalis, Polygenis platensis, Polygenis pradoi, Polygenis rimatus, and Polygenis roberti roberti). In 13 % of fleas of three different species (C. minerva, P. platensis, and P. pradoi) Rickettsia sp. DNA was found. Phylogenetic analysis of concatenated sequences of gltA, htrA, and ompA genes showed that Rickettsia sp. found in rodent fleas (referred as strain Taim) grouped together with Spotted Fever Group Rickettsia. In reference to Bartonella spp., five genotypes were identified in seven fleas of two species (C. minerva and P. platensis) and in five rodent spleens. Also, 207 frozen samples of wild rodents were screened for these pathogens: while none was positive for Rickettsia spp.; five rodent spleens were PCR-positive for Bartonella spp.. Herein, we show the detection of potential novel variants of Bartonella sp. and Rickettsia sp. in fleas collected of wild rodents from Southern Brazil. Further studies are needed to fully characterize these microorganisms, as well as to improve the knowledge on the potential role of Neotropical flea species as diseases vectors.

Molecular survey of Bartonella spp. in rodents and fleas from Chile

The aim of this study was to molecularly survey Bartonella spp. in rodents from the Valdivia Province, Southern Chile and from wild black rat-fleas in Guafo Island, Chilean Patagonia. Thrity-three spleens from synanthropic (Mus musculus, Rattus novergicus and Rattus rattus) and wild (Abrothrix longipilis, Oligoryzomys longicaudatus, Abrothrix sp.) rodents from Valdivia and 39 fleas/flea-pools (Plocopsylla sp. and Nosopsyllus sp.) from R. rattus in Guafo Island were obtained. All samples were screened by high-resolution melting (HRM) real-time PCR for Bartonella ITS locus (190 bp). ITS-Positive samples were further analyzed for two HRM real-time PCR assays targeting Bartonella rpoB (191 bp) and gltA (340 bp) gene fragments. All positive ITS, gltA and rpoB real-time PCR products were purified and sequenced. Bayesian inference trees were built for the gltA and rpoB gene fragments. Bartonella-ITS DNA was detected in 36.3% (12/33) [95% CI (22-53%)] of the tested rodents from Valdivia, being identified in all but O. longicaudatus rodent species captured in this study. ITS DNA was detected in 28% (11/39) [95% CI (16-43%)] of fleas/flea-pools from Guafo Island and identified in both Plocopsylla and Nosopsyllus genera. Sequencing and phylogenic analyses targeting three loci of Bartonella spp. allowed the identification of five genotypes in rodents from Southern Chile, potentially belonging to three different Bartonella spp. Those included Bartonella tribocorum identified from R. rattus, Bartonella rochalimae detected from Abrothix sp., and one novel genotype from uncharacterized Bartonella sp. identified in M. musculus, R. norvegicus, A. longipilis, and Abothrix sp., related to strains previously isolated in Phyllotis sp. from Peru. Additionally, two genotypes of B. tribocorum were identified in fleas from Guafo. In a nutshell, highly diverse and potentially zoonotic Bartonella spp. are described for the first time in wild and synanthropic rodents from Chile, and B. tribocorum was detected in wild back rat fleas from Guafo Island.

Bartonella spp. associated with rodents in an urban protected area, Buenos Aires (Argentina)

At least 15 of the 30 Bartonella species are involved in human pathologies, and several of them are associated with rodents and their fleas. The aims of this study were detect and molecularly characterize the Bartonella infections in rodents from an urban protected area of ​Buenos Aires City (Argentina). A total of 186 rodents were captured and identified. For PCR of the 16S rRNA fragment, 23.7 % of the samples tested positive, and two groups (GrA and GrB) were identified. Likewise, the comparison between the sequences obtained for the gltA gene determined the presence of three genotypes, closely related to Bartonella spp. detected in sigmodontine rodents and their fleas in the Americas, which form a well-separated clade. The high prevalence of Bartonella in rodents from an urban protected area of ​Buenos Aires city is relevant from a public health perspective.

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.

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.

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First record of wild mammals with Bartonella DNA at northwestern of Rio de Janeiro.

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The genotypes of Bartonella were characterized in two species of cricetid rodents and two species of phyllostomid bats from Rio de Janeiro.

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The genotype of Bartonella in Akodon cursor was identified closely related to B. rochalimae.

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This is the first report of Bartonella in C. perspicillata from Rio de Janeiro state, based on the analysis of tissue samples.

Low occurrence of Bartonella in synanthropic mammals and associated ectoparasites in peri-urban areas from Central-Western and Southern Brazil

Worldwide, Bartonella species are known to infect a wide range of mammalian and arthropod hosts, including humans. The current study aimed to investigate the prevalence of Bartonella spp. in synanthropic mammals captured in peri-urban areas from Central-Western and Southern Brazil and their ectoparasites. For this aim, 160 mammals belonging to four species, and 218 associated arthropods were sampled. DNA was extracted and subjected to different Bartonella screening assays. Additionally, blood samples from 48 small rodents were submitted to liquid BAPGM culture followed by qPCR assay and solid culture. Two out of 55 Rattus captured in Santa Catarina state were PCR-positive for Bartonella when targeting the nuoG, 16S, and ITS loci. Sequences showed high homology with Bartonella coopersplainsensis. Conversely, all 48 small rodents, 14 capybaras and 43 opossum DNA samples from animals trapped in Mato Grosso do Sul were Bartonella negative in the HRM real time PCR assays targeting the ITS locus and gltA gene. Additionally, all mammal-associated ectoparasites showed negativity results based on HRM real time PCR assays. The present study showed, for the first time, the occurrence of B. coopersplainsensis in Brazil, shedding some light on the distribution of rats-related Bartonella in South America. In addition, the majority of rodents and marsupials were negative for Bartonella spp. Since B. coopersplainsensis reservoirs - Rattus spp. - are widely dispersed around the globe, their zoonotic potential should be further investigated.

Epidemiology and genetic diversity of zoonotic pathogens in urban rats (Rattus spp.) from a subtropical city, Guangzhou, southern China

Commensal rats (Rattus spp.), which are globally distributed, harbour many pathogens responsible for significant human diseases. Despite this, we have a poor understanding of the epidemiology and genetic diversity of some recently neglected zoonotic pathogens, such as Leptospira spp., Bartonella spp. and hepatitis E virus (HEV), which constitute a major public health threat. Thus, we surveyed the occurrences, co-infection and genetic diversity of these pathogens in 129 urban rats from China. For Rattus tanezumi, the prevalences of Leptospira spp., Bartonella spp. and HEV infection were 6.67%, 0% and 46.67%, respectively. The prevalences of Leptospira spp., Bartonella spp. and HEV infection were 57.89%, 9.65% and 57.89% for Rattus norvegicus respectively. Leptospira spp. and HEV infections were more likely to occur in mature R. norvegicus. Phylogenetic analyses showed that pathogenic Leptospira interrogans and Leptospira borgpetersenii might exist. We also found that Bartonella spp. showed high similarity to Bartonella elizabethae, Bartonella rochalimae and Bartonella tribocorum, which are implicated in human disease. Dual and triple infections were both detected. Moreover, dual infections with Leptospira spp. and HEV represented the most frequent co-infection, and there was a significantly positive association between them. High genetic diversity was observed in genes segments from Leptospira, Bartonella and HEV. Our results first discover the occurrence of multiple co-infections and genetic diversity of Leptospira, Bartonella and HEV in commensal rats from China. Altogether, the present study provides an insight into evaluating the risk of rat-borne zoonoses in urban China.

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 Bartonella spp. in China and St. Kitts

Bartonella are vector-borne hemotropic bacteria that infect a wide variety of hosts, including people. While there are PCR assays that can identify individual or groups of Bartonella, there is no reliable molecular method to simultaneously detect all species while maintaining genus specificity and sensitivity. By comparing highly conserved 16S rRNA sequences of the better-recognized Bartonella spp. on GenBank, we selected primers and probes for a genus-specific pan-Bartonella FRET-qPCR. Then, a gltA-based Bartonella PCR was established by selecting primers for a highly variable region of gltA, of which the sequenced amplicons could identify individual Bartonella spp. The pan-Bartonella FRET-qPCR did not detect negative controls (Brucella spp., Anaplasma spp., Rickettsia spp., Coxiella burnetii, and Wolbachia) but reliably detected as few as two copies of the positive control (Bartonella henselae) per reaction. There was complete agreement between the pan-Bartonella FRET-qPCR and the gltA-based Bartonella PCR in detecting Bartonella in convenience test samples from China and St. Kitts: cats (26%; 81/310), Ctenocephalides felis (20%; 12/60), cattle (24%; 23/98), and donkeys (4%; 1/20). Sequencing of the gltA-based Bartonella PCR products revealed B. henselae (70%; 57/81) and B. clarridgeiae (30%; 24/81) in cats and C. felis (67%; 8/12, and 33%; 4/12, respectively) and B. bovis in cattle (23.5%; 23/98) and donkeys (4.0%; 1/24). The pan-Bartonella FRET-qPCR and gltA-based Bartonella PCR we developed are highly sensitive and specific in detecting recognized Bartonella spp. in a single reaction. The pan-Bartonella FRET-qPCR is convenient requiring no gel electrophoresis and providing copy numbers, while the gltA-based Bartonella PCR reliably differentiates individual Bartonella species. The use of these PCRs should greatly facilitate large-scale surveillance studies and the diagnosis of infections in clinical samples.

Prevalence and diversity of Bartonella species in small rodents from coastal and continental areas

Worldwide, Bartonella infections are known to inflict a wide range of mammals and, within rodents alone, more than 20 Bartonella species have been detected. There is, however, a lack of studies on the presence of Bartonella spp. in rodents in the Baltic region. We analysed 580 individuals belonging to eight small rodent species trapped in coastal and continental areas of Lithuania during 2015-2016. The presence of Bartonella DNA was examined by real-time PCR targeting the ssrA gene. The molecular characterization of the bacteria strains was based on sequence analysis of two housekeeping genes (rpoB, groEL) and the intergenic spacer region (ITS). For the rodents overall, the prevalence of Bartonella spp. was 54.8%, while the prevalence figures for each of the individual species were 8.3% in M. musculus, 15.8% in A. agrarius, 33.3% in M. arvalis, 42.4% in M. glareolus, 53.4% in M. oeconomus, 57.5% in M. minutus, 79.6% in A. flavicollis to 80% in M. agrestis. Sequence analysis revealed that the Bartonella strains belonged to the B. grahamii, B. taylorii, B. rochalimae, B. tribocorum, B. coopersplainsensis and B. doshiae genogroups. The highest Bartonella infection rates and the highest species diversity were both detected in rodents captured in the coastal area. To our knowledge, these are the first reports of the presence of B. coopersplainsensis, B. doshiae and B. tribocorum in Lithuania.

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

Background

Rattus 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.

Methods

In 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.

Results

Overall, 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.

High frequency and molecular characterization of porcine hemotrophic mycoplasmas in Brazil

Mycoplasma suis and Mycoplasma parvum are the two hemotrophic mycoplasmas species described in pigs. M. suis is involved in infectious anemia, while M parvum infection is commonly subclinical. The objectives of this study were twofold: (i) to investigate the prevalence of porcine hemotrophic mycoplasmas in sows from the southern region of Brazil by quantitative real-time PCR (qPCR) and (ii) to genetically characterize a subset of the samples based on the 16S rRNA gene. A total of 429 blood samples were evaluated from 53 different farm sites. Porcine hemoplasmas was detected at all the 53 tested sites and in 79.72% of the samples (342/429). Two sequences were obtained for Mycoplasma spp. The phylogenetic analysis based on the 16S rRNA gene (900 bp) showed that the Mycoplasma sequences were closely related to the M. suis cluster and that one sequence was positioned in the M. parvum cluster. In conclusion, porcine hemoplasmas have a high rate of prevalence in sows from commercial farms in the southern region of Brazil. This study demonstrated the first molecular detection and characterization of partial 16S rRNA gene of M. parvum in Brazil.

Genetic diversity, infection prevalence, and possible transmission routes of Bartonella spp. in vampire bats

Bartonella spp. are globally distributed bacteria that cause endocarditis in humans and domestic animals. Recent work has suggested bats as zoonotic reservoirs of some human Bartonella infections; however, the ecological and spatiotemporal patterns of infection in bats remain largely unknown. Here we studied the genetic diversity, prevalence of infection across seasons and years, individual risk factors, and possible transmission routes of Bartonella in populations of common vampire bats (Desmodus rotundus) in Peru and Belize, for which high infection prevalence has previously been reported. Phylogenetic analysis of the gltA gene for a subset of PCR-positive blood samples revealed sequences that were related to Bartonella described from vampire bats from Mexico, other Neotropical bat species, and streblid bat flies. Sequences associated with vampire bats clustered significantly by country but commonly spanned Central and South America, implying limited spatial structure. Stable and nonzero Bartonella prevalence between years supported endemic transmission in all sites. The odds of Bartonella infection for individual bats was unrelated to the intensity of bat flies ectoparasitism, but nearly all infected bats were infested, which precluded conclusive assessment of support for vector-borne transmission. While metagenomic sequencing found no strong evidence of Bartonella DNA in pooled bat saliva and fecal samples, we detected PCR positivity in individual saliva and feces, suggesting the potential for bacterial transmission through both direct contact (i.e., biting) and environmental (i.e., fecal) exposures. Further investigating the relative contributions of direct contact, environmental, and vector-borne transmission for bat Bartonella is an important next step to predict infection dynamics within bats and the risks of human and livestock exposures.

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.

Seroprevalence of Bartonella spp., Coxiella burnetii, and Hantavirus among people who inject drugs in Rio de Janeiro, Brazil: a retrospective assessment of a biobank

The increasing use of illicit drugs imposes a public health challenge worldwide. People who inject drugs (PWID) are more susceptible to health complications due to immunosuppression associated with drug use and non-hygienic self-administration of substances, contaminants, and liquids. PWID are subjected to increased risk of acquiring and transmitting different pathogens (frequently functioning as sentinel cases for (re)emerging pathogens), including those transmitted by arthropods and vertebrate reservoirs in unhealthy environments. A clear association between injection drug use and HIV, HBV, and HCV infections has been described; however, other infectious viral and bacterial agents have been seldomly assessed. In this study, we investigated the seroprevalence of Bartonella spp., Coxiella burnetii, and Hantavirus among 300 randomly selected PWIDs from Rio de Janeiro, as part of a multi-city cross-sectional study carried out in the 1990s. Point seroprevalences and respective 95% CIs are as follows: 9.3% for C. burnetii (95% CI: 6.0%-13.0%), 1.0% for Bartonella spp. (95% CI: 0.0%-3.0%), and 4.0% for Hantavirus (95% CI: 2.0%-7.0%). In addition to the blood-borne pathogens, the results of this study increase our knowledge on other transmissible infectious agents in PWID. The high seroprevalence of C. burnetii and Hantavirus found among PWID is intriguing and suggests the need to carry out prospective studies, including molecular analyses, to confirm these findings and allow a better understanding of the putative relevance of these zoonotic infectious agents among PWID.

Molecular detection of Bartonella species and haemoplasmas in wild African buffalo (Syncerus caffer) in Mozambique, Africa

The African buffalo (Syncerus caffer), a mammal species whose population is declining, can play a role as a reservoir or carrier of a wide number of arthropod-borne pathogens. Translocation procedures have been used as an alternative approach for species conservation. However, the veterinary aspects of this sort of procedures are extremely important to minimize the impact on animal health. In order to detectBartonellaand haemoplasmas, two important group of bacterial that have an impact in both human and animal health, EDTA whole-blood samples were screened for the presence of these bacterial pathogens by molecular techniques. As a result, a molecular occurrence of 4.1 and 15.4% forBartonellaspp. and haemoplasmas, respectively, was reported among 97 wild buffaloes sampled during a translocation procedure from Marromeu to Gorongosa Reserve, Mozambique. Additionally, phylogenetic analyses of the obtained sequences were conducted. At least, three bovine-associated pathogens, namelyB. bovis,M. wenyoniiand ‘CandidatusM. haemobos’, as well as a probably newBartonellagenotype/species were detected inS. caffer.Further studies are needed in order to determine whether these bacterial species may cause impact in buffaloes and other sympatric ruminant species living in the release site.

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.

Evidence and molecular characterization ofBartonellaspp. and hemoplasmas in neotropical bats in Brazil

The order Chiroptera is considered the second largest group of mammals in the world, hosting important zoonotic virus and bacteria.Bartonellaand hemotropic mycoplasmas are bacteria that parasite different mammals’ species, including humans, causing different clinical manifestations. The present work aimed investigating the occurrence and assessing the phylogenetic positioning ofBartonellaspp. andMycoplasmaspp. in neotropical bats sampled from Brazil. Between December 2015 and April 2016, 325 blood and/or tissues samples were collected from 162 bats comprising 19 different species sampled in five states of Brazil. Out of 322 bat samples collected, while 17 (5·28%) were positive to quantitative PCR forBartonellaspp. based onnuoGgene, 45 samples (13·97%) were positive to cPCR assays for hemoplasmas based on 16S rRNA gene. While seven sequences were obtained forBartonella(nuoG) (n= 3),gltA(n= 2),rpoB(n= 1),ftsZ(n= 1), five 16S rRNA sequences were obtained for hemoplasmas. In the phylogenetic analysis, theBartonellasequences clustered withBartonellagenotypes detected in bats sampled in Latin America countries. All five hemoplasmas sequences clustered together as a monophyletic group by Maximum Likelihood and Bayesian Inference analyses. The present work showed the first evidence of circulation ofBartonellaspp. and hemoplasmas among bats in Brazil.

Zoonotic pathogens in Atlantic Forest wild rodents in Brazil: Bartonella and Coxiella infections

Zoonotic pathogens comprise a significant and increasing fraction of all emerging and re-emerging infectious diseases that plague humans. Identifying host species is one of the keys to controlling emerging infectious diseases. From March 2007 until April 2012, we collected a total of 131 wild rodents in eight municipalities of Rio de Janeiro, Brazil. We investigated these rodents for infection with Coxiella burnetii, Bartonella spp. and Rickettsia spp. In total, 22.1% (29/131) of the rodents were infected by at least one pathogen; co-infection was detected in 1.5% (2/131) of rodents. Coxiella burnetii was detected in 4.6% (6/131) of the wild animals, 17.6% of the rodents harbored Bartonella spp. No cases of Rickettsia were identified. Bartonella doshiae and Bartonella vinsonii were the species found on the wild mammals. This report is the first to note C. burnetii, B. doshiae and B. vinsonii natural infections in Atlantic Forest wild rodents in Brazil. Our work highlights the potential risk of transmission to humans, since most of the infected specimens belong to generalist species that live near human dwellings.