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.     

Bartonella spp. in cats from Buenos Aires,Argentina

In Argentina, data on the presence of members of the genus Bartonella is scarce. To increase knowledge about these zoonotic pathogens in this country, the presence and variability of Bartonella spp. was investigated in cats and dogs from Buenos Aires. Bartonella spp. was detected in 17.8% of cats, while all dogs tested negative by PCR and Reverse Line Blot. B. henselae was the most frequent species, being detected in 11.9% (14/101), while B. clarridgeiae was found in only 5.9% (6/101) of the cats. Afterwards, B. henselae isolates and positive blood samples were characterized by Multiple Locus Sequence Typing (MLST) and Multiple Locus Variable Number Tandem Repeats Analysis (MLVA). As result, four different MLST sequence types (ST) and eight MLVA profiles were identified. ST 1 was the most frequent variant found in cats, followed by ST 8. Interestingly, some of the MLVA profiles that were detected in this study have been previously associated with human disease, and represents a potential risk of infection. Veterinarians and physicians should consider the presence of these emerging pathogens in their diagnostic routine.     

Flea species infesting dogs in Florida and Bartonella spp. prevalence rates

Several Bartonella spp. associated with fleas can induce a variety of clinical syndromes in both dogs and humans. However, few studies have investigated the prevalence of Bartonella in the blood of dogs and their fleas. The objectives of this study were to determine the genera of fleas infesting shelter dogs in Florida, the prevalence of Bartonella spp. within the fleas, and the prevalence of Bartonella spp. within the blood of healthy dogs from which the fleas were collected. Fleas, serum, and EDTA-anti-coagulated whole blood were collected from 80 healthy dogs, and total DNA was extracted for PCR amplification of Bartonella spp. The genera of fleas infesting 43 of the dogs were determined phenotypically. PCR amplicons from blood and flea pools were sequenced to confirm the Bartonella species. Amplicons for which sequencing revealed homology to Bartonella vinsonii subsp. berkhoffii (Bvb) underwent specific genotyping by targeting the 16S–23S intergenic spacer region.A total of 220 fleas were collected from 80 dogs and pooled by genus (43 dogs) and flea species. Bartonella spp. DNA was amplified from 14 of 80 dog blood samples (17.5%) and from 9 of 80 pooled fleas (11.3%). B. vinsonii subsp. berkhoffii DNA was amplified from nine dogs and five of the flea pools. Bartonella rochalimae (Br) DNA was amplified from six dogs and two flea pools. One of 14 dogs was co-infected with Bvb and Br. The dog was infested with Pulex spp. fleas containing Br DNA and a single Ctenocephalides felis flea. Of the Bvb bacteremic dogs, five and four were infected with genotypes II and I, respectively. Of the Bvb PCR positive flea pools, three were Bvb genotype II and two were Bvb genotype I.Amplification of Bvb DNA from Pulex spp. collected from domestic dogs, suggests that Pulex fleas may be a vector for dogs and a source for zoonotic transfer of this pathogen from dogs to people. The findings of this study provide evidence to support the hypothesis that flea-infested dogs may be a reservoir host for Bvb and Br and that ectoparasite control is an important component of shelter intake protocols.     

Diversity of Bartonella species detected in arthropod vectors from animals in Australia

A variety of Bartonella species were detected in two species of ticks and three species of fleas collected from marsupial hosts; brush-tailed bettong or woylie (Bettongia penicillata) and western barred bandicoots (Perameles bougainville) and from a rodent host; Rattus fuscipes in Western Australia. Bartonella species were detected using nested-PCR of the gltA gene and the 16S–23S ribosomal internal transcribed spacer region (ITS), and species were characterized using DNA sequencing of the 16S rRNA, gltA, rpoB, ftsZ genes and the ITS region. Bartonella rattaustraliani and B. coopersplainsensis were detected in Ixodes spp. ticks and fleas (Stephanocircus pectinipes) respectively collected from rodents. Two novel Bartonella species were detected from marsupials; Candidatus Bartonella woyliei n. sp. was detected in both fleas (Pygiopsylla hilli) and ticks (Ixodes australiensis) collected from woylies and Candidatus Bartonella bandicootii n. sp. was detected in fleas (Pygiopsylla tunneyi) collected from western barred bandicoots. Concatenated phylogenetic analysis of all 5 loci clarified the marsupial cluster of Bartonella species in Australia and confirmed the species status of these two Bartonella species in ticks and fleas from woylies and western barred bandicoots, which are classified as threatened species and are vulnerable to extinction.     

Bartonella washoensis infection in red squirrels (Sciurus vulgaris) and their ectoparasites in Lithuania

This is the first study to investigate the presence of Bartonella infections in different internal organs of red squirrels and their ectoparasites in Lithuania. A total of 39 roadkill red squirrels were collected. Squirrels were infested with Ixodes ricinus ticks (191) and Ceratophyllus sciurorum fleas (36). The presence of Bartonella spp. was screened using 16 S–23 S rRNA internal transcribed spacer region and bacteria were detected in 38.5 % (15/39) samples of squirrels, 1.0 % (2/191) samples of ticks and 55.5 % (20/36) samples of fleas. The infection rate of different internal organs of squirrels varied from 11.1%–47.4%. The 16 S–23 S rRNA ITS region sequences showed that Bartonella washoensis were detected in squirrels and their ectoparasites. The results from this study support the hypothesis that S. vulgaris and their fleas, C.sciurorum, serve as a major reservoir and a vector, respectively, of zoonotic B. washoensis in Lithuania.     

Prevalence of Bartonella species,Rickettsia felis,haemoplasmas and the Ehrlichia group in the blood of cats and fleas in eastern Australia

Objectives To define the prevalence of Bartonella spp., Rickettsia felis, Mycoplasma haemofelis, ‘Candidatus Mycoplasma haemominutum’ (Mhm) and ‘Candidatus Mycoplasma turicensis’ (Mtc) in cats and their fleas in eastern Australia. Design and procedure Conventional PCR assays that detect Bartonella spp., M. haemofelis, Mhm, Mtc, Rickettsia spp., Ehrlichia spp., Anaplasma spp. and Neorickettsia spp. were performed on DNA extracted from blood and fleas collected from 111 cats. Cat sera were assayed by ELISA for IgG of Bartonella spp. Results DNA of M. haemofelis, Mtc and Mhm was amplified from 1 (0.9%), 1 (0.9%) and 17 cats (15.3%), respectively. Only DNA of Mhm was amplified from the 62 of 111 pooled flea samples (flea sets; 55.9%). Overall, the prevalence rates for Bartonella spp. DNA in the cats and the flea sets was 16.2% (18 cats) and 28.8% (32 flea sets), respectively. Bartonella spp. IgG was detected in 42 cats (37.8%), of which 11 (26.2%) were positive for Bartonella spp. DNA in their blood. R. felis DNA was amplified from 22 flea sets (19.8%), but not from cats. Overall, DNA of one or more of the organisms was amplified from 27% (30) of cats and 67.6% (75) of the flea sets. Conclusions This is the first Australian study to determine the prevalence of R. felis and B. clarridgeiae in both fleas and the cats from which they were collected. Flea-associated infectious agents are common in cats and fleas in eastern Australia and support the recommendation that stringent flea control be maintained on cats.     

Modelling relative abundance of Oligoryzomys flavescens,an Orthohantavirus reservoir,in an endemic hantavirus pulmonary syndrome zone

Hantavirus pulmonary syndrome (HPS) is a zoonotic emerging infectious disease caused by New World orthohantaviruses (family Hantaviridae) hosted by rodents of the family Cricetidae. In Argentina, one of its main hosts is the sigmodontine rodent Oligoryzomys flavescens, a widely distributed mouse of the Pampas, Delta and Espinal ecoregions of central-east Argentina. Because the abundance of the reservoir and its proportion in the rodent community affects both virus prevalence and human exposure risk, its estimation throughout its known geographical distribution is of key importance for the design of public health strategies to prevent HPS. The aim of this study was therefore to model the relative abundance of O. flavescens in most of the Pampas ecoregion within Buenos Aires Province, Argentina, where hantavirus pulmonary syndrome is endemic. To do this we used owl-pellet samples collected between 2006 and 2008 from 51 sites distributed throughout most of Buenos Aires province. Mammalian prey in each pellet was identified to the lowest possible taxonomic level by examination of the skulls, dentaries and molars. We modelled the frequency of O. flavescens found in each sample as a function of climatic, environmental, and topographic data of each site. The two best models were applied to a Geo referential Information System to build maps of estimated frequency (as a proxy of relative abundance) within Buenos Aires province. Estimated relative abundance of O. flavescens in Buenos Aires province was significantly associated with annual mean temperature, annual precipitation and presence of freshwater bodies, and varied among sub-regions, with the Inland and Rolling Pampas being the regions with highest frequencies. Knowing in which areas O. flavescens abundance is expected to be higher can be used to concentrate limited sanitary efforts in those areas that are most needed in order to reduce transmission and increase detection.     

Prevalence of zoonotic Bartonella species among rodents and shrews in Thailand

We investigated the prevalence of Bartonella species in 10 rodent and one shrew species in Thailand. From February 2008 to May 2010, a total of 375 small animals were captured in 9 provinces in Thailand. Bartonella strains were isolated from 57 rodents (54 from Rattus species and 3 from Bandicota indica) and one shrew (Suncus murinus) in 7 of the 9 provinces, and identified to the species level. Sequence analysis of the citrate synthase and RNA polymerase β subunit genes identified the 58 isolates from each Bartonella-positive animal as B. tribocorum in 27 (46.6%) animals, B. rattimassiliensis in 17 (29.3%) animals, B. elizabethae in 10 (17.2%) animals and B. queenslandensis in 4 (6.9%) animals. R. norvegicus, R. rattus, and Suncus murinus carried B. elizabethae, which causes endocarditis in humans. The prevalence of Bartonella bacteremic animals by province was 42.9% of the animals collected in Phang Nga, 26.8% in Chiang Rai, 20.4% in Sa Kaeo, 16.7% in Nakhon Si Thammarat, 12.0% in Surat Thani, 9.1% in Mae Hong Son and Loei Provinces.     

The role of the subterranean rodent Ctenomys talarum (Rodentia: Octodontidae) in the life cycle of Taenia taeniaeformis (Cestoda: Taeniidae) in urban environments

This work is the first report of subterranean rodent Ctenomys talarum (Rodentia: Octodontidae) as intermediate host of Taenia taeniaeformis in urban areas of Mar de Cobo (Buenos Aires Province, Argentina) and to experimentally reproduce in domestic dogs the adult stage of this parasite. Prevalence, mean abundance and mean intensity of infection with T. taeniaeformis larvae in the liver and peritoneal cavity of C. talarum were 64%, 15.3 and 9.8, respectively. Ten adults of T. taeniaeformis were obtained from experimentally infected dogs. Information about the role of subterranean rodents in the life cycle of this parasite is also given. The above mentioned data indicate that T. taeniaeformis is a frequent parasite of this species of rodents, at least within the study area. Also explanations for the high prevalence of larval forms of this parasite in C. talarum populations are given.     

Flea-borne pathogens in the cat flea Ctenocephalides felis and their association with mtDNA diversity of the flea host

Flea-borne pathogens were screened from 100 individual cat fleas using a PCR approach, of which 38 % were infected with at least one bacterium. Overall, 28 % of the flea samples were positive for Bartonella as inferred from ITS DNA region. Of these, 25 % (7/28) were identified as Bartonella clarridgeiae, 42.9 % (12/28) as Bartonella henselae consisted of two different strains, and 32.1 % (9/28) as Bartonella koehlerae, which was detected for the first time in Malaysia. Sequencing of gltA amplicons detected Rickettsia DNA in 14 % of cat flea samples, all of them identified as Rickettsia asembonensis (100 %). None of the flea samples were positive for Mycoplasma DNA in 16S rRNA gene detection. Four fleas were co-infected with Bartonella and Rickettsia DNAs. Statistical analyses reveal no significant association between bacterial infection and mtDNA diversity of the cat flea. Nevertheless, in all types of pathogen infections, infected populations demonstrated lower nucleotide and haplotype diversities compared to uninfected populations. Moreover, lower haplotype numbers were observed in infected populations.     

New records of bacteria in different species of fleas from France and Spain

In this study, we assessed the presence of vector-borne microorganisms in different species of fleas collected from different hosts in diverse areas of South-Western Europe by molecular methods. A total of 319 fleas belonging to eight different species was tested for the presence of eight microorganisms. Wolbachia spp. endosymbionts were detected in Ctenocephalides felis, Pulex irritans, Archaeopsylla erinacei and Ctenophthalmus baeticus boisseauorum specimens. Rickettsia felis, an emerging pathogen, was detected in C. felis, A. erinacei and Ct. b. boisseauorum. Rickettsia typhi, the agent of murine typhus was detected for the first time in A. erinacei and Mycobacterium spp. were detected for the first time in fleas (C. felis, P. irritans and A. erinacei). Lastly, five different species of Bartonella were detected in fleas’ DNA in this study, including a possible new bacterium belonging to this genus. With this study, we updated the knowledge of the flea-borne bacteria present in the South-West of Europe reinforcing the idea about the necessity to expand and increase the current knowledge on flea-borne pathogens.     

Cryptosporidium parvum GP60 subtypes in dairy cattle from Buenos Aires,Argentina

Cryptosporidium parvum from 73 dairy calves less than two months old from Buenos Aires province (Argentina) were molecularly characterized using sequence analysis of the GP60 gene. Seventy-five sequences were obtained, and seven different subtypes were identified, all belonging to the IIa subtype family. The most common subtypes were IIaA20G1R1 (27/75), IIaA22G1R1 (16/75), and IIaA18G1R1 (13/75). Subtypes IIaA21G1R1, IIaA23G1R1, IIaA16G1R1 and IIaA19G1R1 were found sporadically. Two samples contained mixed infections with IIaA21G1R1 and IIaA22G1R1. A significant association was found between subtypes and geographic location, whereas there was no relation between subtypes and presence of diarrhea. Three of the subtypes found in this study (IIaA16G1R1, IIaA18G1R1, and IIaA19G1R1) were previously identified in humans. These findings suggest that cattle could play an important role in the transmission of cryptosporidiosis to humans in Buenos Aires province.     

Bartonella,bats and bugs: A review

Ecological, immunological, and epidemiological factors enable bats to transmit an increasingly recognized spectrum of zoonotic agents, and bartonellae are among those emerging pathogens identified in bats and their arthropod ectoparasites. Current data reveal a multifaceted disease ecology where diverse host species distributed around the world interact with a number of Bartonella spp. and several potential vectors. This review summarizes the methods and findings of studies conducted since 2005 to illustrate that Bartonella bacteremia varies by bat species, location, and other potential variables, such as diet with a very high prevalence in hematophagous bats. Among bat families, Bartonella prevalence ranged from 7.3% among Nycteridae to 54.4% in Miniopteridae. Further research can build on these current data to better determine risk factors associated with Bartonella infection in bat populations and the role of their ectoparasites in transmission.     

Bartonella species and their ectoparasites: selective host adaptation or strain selection between the vector and the mammalian host?

A wide range of blood-sucking arthropods have either been confirmed or are suspected as important vectors in Bartonella transmission to mammals, including humans. Overall, it appears that the diversity of Bartonella species DNA identified in ectoparasites is much broader than the species detected in their mammalian hosts, suggesting a mechanism of adaptation of Bartonella species to their host-vector ecosystem. However, these mechanisms leading to the fitness between the vectors and their hosts still need to be investigated.     

Detection of Bartonella spp. in wild rodents in Israel using HRM real-time PCR

The prevalence of Bartonella spp. in wild rodents was studied in 19 geographical locations in Israel. One hundred and twelve rodents belonging to five species (Mus musculus, Rattus rattus, Microtus socialis, Acomys cahirinus and Apodemus sylvaticus) were included in the survey. In addition, 156 ectoparasites were collected from the rodents. Spleen sample from each rodent and the ectoparasites were examined for the presence of Bartonella DNA using high resolution melt (HRM) real-time PCR. The method was designed for the simultaneous detection and differentiation of eight Bartonella spp. according to the nucleotide variation in each of two gene fragments (rpoB and gltA) and the 16S–23S intergenic spacer (ITS) locus, using the same PCR protocol which allowed the simultaneous amplification of the three different loci. Bartonella DNA was detected in spleen samples of 19 out of 79 (24%) black rats (R. rattus) and in 1 of 4 (25%) Cairo spiny mice (A. cahirinus). In addition, 15 of 34 (44%) flea pools harbored Bartonella DNA. Only rat flea (Xenopsyla cheopis) pools collected from black rats (R. rattus) were positive for Bartonella DNA. The Bartonella sp. detected in spleen samples from black rats (R. rattus) was closely related to both B. tribocorum and B. elizabethae. The species detected in the Cairo spiny mouse (A. cahirinus) spleen sample was closely related to the zoonotic pathogen, B. elizabethae. These results indicate that Bartonella species are highly prevalent in suburban rodent populations and their ectoparasites in Israel. Further investigation of the prevalence and zoonotic potential of the Bartonella species detected in the black rats and the Cairo spiny mouse is warranted.     

Detection and phylogenetic analysis of Bartonella species from bat flies on eastern bent-wing bats (Miniopterus fuliginosus) in Japan

We examined Bartonella prevalence in 281 bat flies collected from 114 eastern bent-wing bats (Miniopterus fuliginosus) in Japan and phylogenetically analyzed with other bat fly and bat strains. The bat flies were identified as Penicilidia jenynsii (PJ; n = 45), Nycteribia allotopa (NA; n = 157), and novel Nycteribia species (NS; n = 79). Bartonella DNAs were detected in 31.7 % (89/281) of bat flies by PCR targeting the citrate synthase (gltA) gene. The prevalence of Bartonella DNA among the bat flies was 47.1 % (74/157) in NA, 15.2 % (12/79) in NS, and 6.7 % (3/45) in PJ. Bartonella bacteria were also isolated from two NA and one NS. A phylogenetic analysis of the gltA sequences revealed that bat fly-associated strains were classified into three lineages and the same lineages of Bartonella were commonly detected from both Nycteribia bat flies and Miniopterus bats. These results suggest that Nycteribia bat flies are potential vectors for transmitting Bartonella among Miniopterus bats.     

Bartonella bovis and Bartonella chomelii infection in dairy cattle and their ectoparasites in Algeria

Bartonella are blood-borne and vector-transmitted bacteria, some of which are zoonotic. B. bovis and B. chomelii have been reported in cattle. However, no information has yet been provided on Bartonella infection in cattle in Algeria. Therefore, 313 cattle from 45 dairy farms were surveyed in Kabylia, Algeria, in order to identify Bartonella species infecting cattle using serological and molecular tests. In addition, 277 ticks and 33 Hippoboscidae flies were collected. Bartonella bovis and B. chomelii were identified as the two species infecting cattle. Bartonella DNA was also amplified from 6.8 % (n = 19) of ticks and 78.8 % (n = 26) of flies. Prevalence of B. bovis DNA in dairy cattle was associated both with age and altitude. This study is the first one to report of bovine bartonellosis in Algeria, both in dairy cattle and in potential Bartonella vectors, with the detection of B. bovis DNA in tick samples and B. chomelii in fly samples.     

First report of Enterocytozoon bieneusi from dairy cattle in Argentina

Fecal specimens were obtained from a total of 70 dairy calves less than two months old on 11 municipalities in Buenos Aires, Argentina. After removal of fecal debris by sieving and sucrose flotation, specimens were subjected to PCR to detect the presence of Enterocytozoon bieneusi. PCR revealed a 14.3% of prevalence for E. bieneusi with 10 positive calves from 7 municipalities. Gene sequence analysis conducted in all samples positives by PCR revealed the presence of six genotypes; four previously reported in cattle as well as humans (D, I, J, and BEB4), one never reported in cattle before but previously reported in humans (EbpC), and one novel genotype (BEB10). These results constitute the first molecular characterization of E. bieneusi in Argentina, and suggest a potential risk of zoonotic transmission in this area.     

Isolation and phylogenetic analysis of Bartonella species from Rusa deer (Rusa timorensis) in Thailand

The aim of the present study is to investigate the prevalence of Bartonella infection in deer in Thailand and to characterize the isolates by biochemical, morphological and genetic analysis. A total of 247 blood samples were collected from Rusa deer (Rusa timorensis) in a livestock breeding facility in Thailand. Bartonella bacteria were isolated in 3.6% of the blood samples. Three out of 110 (2.7%) males and 6 of 137 (4.4%) females were positive for Bartonella. A higher prevalence of Bartonella was observed in young deer under 4 years of age compared to adults over 4 years of age, but no Bartonella was isolated from deer over 8 years of age. Phylogenetic analysis of concatenated sequences of seven loci of Bartonella indicated that all the isolates from Rusa deer in Thailand were identical and formed a distinct cluster from other known Bartonella species.     

Epidemiology of Bartonella Infection in Rodents and Shrews in Taiwan

During the period of August 2002 and November 2004, an epidemiological investigation for Bartonella infection was conducted in small mammals in Taiwan. Using whole blood culture on chocolate agar plates, Bartonella species were successfully isolated from 41.3% of the 310 animals tested. The isolation rate of Bartonella species varied among different animal species, including 52.7% of the 169 Rattus norvegicus, 28.6% of the 126 Sucus murinus, 10% of the 10 Rattus rattus and 66.7% of the three Rattus losea. Bacteremia prevalence also varied with the origin of the animals, as 56.2% of the animals captured on farms, 38.6% of the ones captured at harbour sites and 11.8% of the animals captured from urban areas were bacteremic. Through molecular analysis of the gltA gene and 16S/23S intergenic spacer region, genetic diversity of Bartonella organisms was identified, including strains closely related to Bartonella tribocorum, Bartonella grahamii, Bartonella elizabethae, Bartonella phoceensis and Bartonella rattimassiliensis. Moreover, this is the first report of zoonotic B. elizabethae and B. grahamii identified in R. losea, the lesser rice‐field rat. Various Bartonella species were identified in R. norvegicus, compared to 97.2% of Suncus murinus with unique Bartonella species. By indirect immunofluorescence antibody test, using various rodent Bartonella species as antigens, consistently low percentage of seropositivity implied that small mammals may play a role as competent reservoirs of Bartonella species in Taiwan. Future studies need to be conducted to determine whether these Bartonella species would be responsible for human cases of unknown fever or febrile illness in Taiwan, especially zoonotic B. elizabethae and B. grahamii.