Human seroreactivity against Bartonella species in the Democratic Republic of Congo

ObjectiveTo assess the presence and identity of Bartonella species in a pool of human blood samples from DRC Congo.MethodsBlood (±120μL) was collected anonymously from Congolese patients and placed on calibrated filter papers. Bartonella serology determination was performed using an indirect immunofluorescence assay (IFA) against six specific Bartonella antigens and Coxiella burnetii (C. burnetii) antigen. The end cut-off value for Bartonella sp. was a titre greater than 1:200.ResultsNone of the patients was positive for Bartonella elizabethae, Bartonella vinsonii subsp. vinsonii or Bartonella vinsonii subsp. arupensis nor for C. burnetti, but 4.5% of the 155 samples were positive for either Bartonella henselae, Bartonella quintana, or Bartonella clarridgeiae.ConclusionsThis preliminary study presents the first report of Bartonella species in the DR Congo and the first report of antibodies to Bartonella clarridgeiae in an African human population. Although few experimental trials have established the link between fleas and Bartonella transmission, the repeated detection of similar Bartonella species in fleas and humans in several countries suggests that Bartonellosis could be another flea-borne disease which specific reservoirs are still unknown.     

Zoonotic Bartonella species in fleas and blood from red foxes in Australia

Bartonella are arthropod-borne, fastidious, Gram-negative, and aerobic bacilli distributed by fleas, lice, sand flies, and, possibly, ticks. The zoonotic Bartonella species, Bartonella henselae and Bartonella clarridgeiae, which are the causes of cat scratch disease and endocarditis in humans, have been reported from cats, cat fleas, and humans in Australia. However, to date, there has been no report of B. henselae or B. clarridgeiae in Australian wild animals and their ectoparasites. B. henselae and B. clarridgeiae were detected in fleas (Ctenocephalides felis) from red foxes (Vulpes vulpes), an introduced pest animal species in Australia, and only B. clarridgeiae was detected in blood from one red fox. Phylogenetic analysis of the ribosomal intergenic spacer region revealed that the B. henselae detected in the current study were related to B. henselae strain Houston-1, a major pathogenic strain in humans in Australia, and confirmed the genetic distinctness of B. clarridgeiae. The identification and characterization of Bartonella species in red foxes in the Southwest of Western Australia suggests that red foxes may act as reservoirs of infection for animals and humans in this region.     

Capreolus capreolus and Ixodes ricinus as a reservoir of Bartonella in north-western Poland

Capreolus capreolus and Ixodes ricinus as a reservoir of Bartonella in north-western Poland. The purpose of the study was to assess the prevalence Bartonella in Capreolus capreolus from north-western Poland forest. Supplementary, ticks infesting roe deer were also screened in order to ascertain their role as vectors and reservoirs of Bartonella. The samples of blood from 98 animals from north-western Poland were PCR-screened. Bartonella DNA was detected by using primers complementary to the intergenic spacer (ITS) between the 16S and 23S rRNA genes, which is used for identification of over a dozen species of this genus. Products of three different sizes were detected: 230 bp and 290 bp may represent two strains of B. capreoli, and 190 bp may be identify as B. bovis. All three amplicons were detected in blood, the 290 bp fragment from B. capreoli was present only in ticks, Ixodes ricinus. Generally, Bartonella infection in C. capreolus amounted to 21.4% of individuals, but was much higher during the autumn-winter seasons (62%), than in spring (4.3%). The results show that C. capreolus may be a reservoir for at least two species, i.e. B. capreoli and B. bovis, and probably do not cause persistent infection in roe deer. The high percentage of infested individuals during spring (84%) and infection detected in I. ricinus (5.2%) show that ticks are reservoir and vector of Bartonella.     

Ectoparasites and associated pathogens of free-roaming and captive animals in zoos of South Carolina

A survey of ectoparasites and their associated pathogens was conducted in two South Carolina zoos, from 2004 to 2007. Dead, wild birds and mammals, as well as captive animals examined during routine veterinary checks constituted the study populations. Ectoparasites were tested for species of Anaplasma, Bartonella, Coxiella burnetii, Ehrlichia, Rickettsia, and Trypanosoma. Forty-six species of ectoparasites were collected from 133 free-roaming and captive hosts and their associated nesting and bedding materials. Six vector-borne pathogens were detected molecularly in the ectoparasites, including Anaplasma phagocytophilum in the tick Ixodes dentatus Marx from an eastern cottontail rabbit, Bartonella clarridgeiae in the cat flea Ctenocephalides felis (Bouché) from a Virginia opossum, Bartonella sp. Oh6 in the squirrel flea Orchopeas howardi (Baker) from an eastern grey squirrel, Bartonella sp. T7498 in the sucking louse Neohaematopinus sciuri Jancke from a squirrel, Rickettsia sp. Rf2125 in C. felis from a zookeeper and a grizzly bear, and Rickettsiales sp. Ib 2006 in Ixodes brunneus Koch from an American crow. While the pathology of some of these pathogens is poorly known, Anaplasma phagocytophilum (causative agent of human granulocytic anaplasmosis) and Bartonella clarridgeiae (causative agent of a disease similar to cat-scratch disease) can infect humans. Ectoparasites and their pathogens, especially those originating from free-roaming animals, present a potential threat to captive animals and humans.     

Bartonella species in small mammals and their ectoparasites in Taiwan

Bartonella spp. prevalence in small mammals and their ectoparasites was investigated in Taiwan. Blood samples were obtained from 66 rats, 20 shrews, 276 mites (Laelaps spp.), 74 fleas (Xenopsylla cheopis), 81 lice (Polyplax spp.), and 47 ticks (41 Dermacentor spp. and 6 Ixodes spp.). Bartonellae were isolated or detected in 27 (31.4%) animals. Bartonella DNA was detected in 48 (64.9%) fleas and 11 (64.7%) pooled lice samples, but not in mite and tick samples. Bartonella phoceensis, B. queenslandensis, B. tribocorum, B. elizabethae, and B. rattimassiliensis were isolated or detected in bacteremic mammals. For the first time in Taiwan, B. tribocorum, B. elizabethae, B. queenslandensis, and a B. rochalimae-like strain were detected in fleas, and B. tribocorum, B. phoceensis, and B. rattimassiliensis were detected in lice obtained from small mammals. A broader range of Bartonella species was identified in the ectoparasites than in the small mammals.     

First molecular evidence of new Bartonella spp. in fleas and a tick from Peru

Fleas, lice, and ticks collected in Peru in a suburban area of Cusco in November 1998 were tested by polymerase chain reaction for the presence of Bartonella DNA using primers amplifying a fragment of the intergenic spacer region (ITS) gene. Three new Bartonella genotypes were detected in Pulex fleas self-collected from the beds and clothes of schoolchildren and adults. A fourth new genotype was also detected from a tick found on a sheep in the same area. One of the genotypes is closely related to B. vinsoni subsp. berkhoffii, and the others seem to originate from unknown Bartonella species, whose medical importance has yet to be clarified.     

Diversity of Bartonella genotypes in Richardson's ground squirrel populations

The diversity and dynamics of Bartonella genotypes found in wild Richardson's ground squirrels (RGS), Spermophilus richardsonii were monitored at multiple sites in Saskatchewan, Canada from 2002 to 2004. Based on sequence analysis of a portion of the Bartonella citrate synthase (gltA) gene, four different genotypes were detected in 233 isolates from 176 animals. The majority (87%) of sequences were identified as genotype H, with genotypes I, J, and K accounting for 8%, 4%, and 1% of sequences, respectively. Only one animal was concurrently infected with multiple Bartonella genotypes. Of 23 animals sampled four times or more, 26% were never infected with Bartonella. Of 32 RGS infected with Bartonella at first capture and then sampled again the following month, 50% were infected with the same Bartonella genotype, 41% were no longer infected, and 9% were infected with a different Bartonella genotype in the subsequent sample. The diversity of Bartonella genotypes varied among sites. At one site almost all RGS were infected with genotype H in September, and up to 60% of the same population was infected with genotype I the following spring. We compare our results with previous studies of Bartonella infections in rodents and discuss possible explanations for the observed differences.     

Prospective studies of Bartonella of rodents. Part II. Diverse infections in a single rodent community

The genetic diversity of Bartonella species within a small mammal community and in individual cotton rats (Sigmodon hispidus) was examined by trapping, capturing, sampling, and releasing of marked animals over a 17-month interval. Based on sequence analyses of the Bartonella gltA gene, amplicons separated into four genogroups (A, B, C, and Pin) containing 11 variants. Although the prevalence of bacteremia due to different genogroups/variants of Bartonella was temporally variable, variants of genogroup A predominated during each sampling period. Multiple gltA variants were often (20.5% of individuals) isolated from a single cotton rat blood sample; a maximum of five variants was recovered from an individual during its sampling history. Among 92 cotton rats bacteremic at two or more sampling dates, 34 rats retained a single genetic variant, alone or in mixed infection, throughout their sampling history. The temporal course of individual infections was complex as the succession of gltA variants was variable and detectable bacteremia was often intermittent. No antibodies (titer of >1:8) were detected to homologous strains of Bartonella recovered from individual cotton rats during their sampling history. The temporal course of Bartonella infections could result from a single, persistent, and potentially multi-genogroup/variant infection, during which variants differentially dominate the detectable bacteremia.     

Survey of Bartonella species infecting intradomicillary animals in the Huayllacallán Valley, Ancash, Peru, a region endemic for human bartonellosis.

The natural cycle of Bartonella bacilliformis remains uncertain, and the suspected existence of animal reservoirs for the bacterium has never been convincingly demonstrated. We conducted a survey of Bartonella species infecting intradomicillary animals in a bartonellosis-endemic region of Peru, obtaining blood from 50 animals living in the homes of 11 families whose children had recently had bartonellosis. Bartonella-like bacteria were recovered from four of nine small rodents included in the study, but from none of the 41 domesticated animals. Identification and comparison of these isolates, and two Bartonella-like isolates obtained from Phyllotis mice in a different endemic region of Peru using serologic and genotypic methods indicated that although none were strains of B. bacilliformis, five were probably representatives of three previously unrecognized Bartonella species and one was a likely strain of the pathogenic species B. elizabethae.     

Prospective studies of Bartonella of rodents. Part I. Demographic and temporal patterns in population dynamics

The temporal dynamics of Bartonella infections in a rodent community were described by repeatedly capturing and sampling individual animals. Among six rodent species, from which bartonellae were isolated, cotton rats (Sigmodon hispidus) accounted for > 98% of the bacteremic animals. All cotton rats captured four or more times were Bartonella-culture positive at least once. The lowest monthly prevalence of Bartonella in cotton rats was in June (49%) and the highest was in October (95%). Prevalence of Bartonella infection increased to > 90% among juvenile and subadult rats before declining to < 40% among the largest-oldest individuals. Bacteremia levels ranged between 40 and 4.0 x 10(6) colony forming units (CFU) per 1 mL of blood. Male cotton rats had significantly higher CFUs than females (p = 0.006). The median of Bartonella bacteremia decreased monotonically by age group among cotton rats. Although Bartonella infections were highly prevalent among cotton rats, only 8.5% of rats had reactive antibodies at titers of > or = 1:32 and none had antibodies titers of > 1:256.     

Prevalence and diversity of Bartonella in rodents of northern Thailand: a comparison with Bartonella in rodents from southern China

We report results of the first study to investigate the distribution and diversity of Bartonella in rodents from Thailand. Whole blood from 195 rodents, representing six species, was tested for the presence of Bartonella species using standard culture techniques. Isolates were obtained from 17 (8.7%) of the samples, and 14 of those isolates represented distinct strains, based upon partial sequencing of the citrate synthase (gltA) gene. Phylogenetic analysis of the isolates and other Bartonella species indicated that five unique isolates from Bandicota indica form a cluster that may represent a new Bartonella species. Two additional isolates from B. indica clustered together, and were nearly identical to an isolate from Apodemus draco collected in southern China. Importantly, a number of the isolates from Thailand rodents are closely related to B. grahamii and B. elizabethae, species which have been associated with human illness.     

浙江省鼠形动物巴尔通体的遗传进化分析

目的分析浙江省鼠形动物中巴尔通体分子遗传进化关系,为巴尔通体人群感染的预防控制提供科学依据。方法用夹夜法在浙江省不同地区、不同季节捕获鼠形动物,无菌操作取鼠肝和脾,用PCR和分离培养检测巴尔通体,对部分阳性产物测序,提交到GenBank,用CLUSTAL W进行匹配,然后用PAUP4.0beta10软件构建系统关系,分析其遗传进化关系。结果我们分别从黑线姬鼠、黄毛鼠、褐家鼠、黑腹绒鼠、社鼠、臭鼩鼱、东方田鼠、黄胸鼠和大林姬鼠中检测到巴尔通体特异DNA片段,浙江首次从黑线姬鼠脾中分离出一株巴尔通体。遗传进化分析显示我们检测到的巴尔通体与Bartonellaratti massiliensis以及对人类有致病性的B.grahamii的遗传关系最近。结论浙江省鼠类中广泛存在巴尔通体感染,而且携带人类致病性巴尔通体,存在人群感染风险。     

Bartonella infection in shelter cats and dogs and their ectoparasites

Mainly through vector transmission, domestic cats and dogs are infected by several Bartonella spp. and represent a large reservoir for human infections. This study investigated the relationship of prevalences of Bartonella infection in shelter dogs and cats and various ectoparasite species infesting them (fleas, ticks, and lice). Moreover, relationships between Bartonella infection and animal gender and age and presence of ectoparasites were analyzed. Blood samples were collected from 120 dogs and 103 cats. There were 386 ticks and 36 fleas harvested on these dogs, and 141 fleas, 4 ticks, and 2 lice harvested on these cats. Isolation/detection of Bartonella sp. was performed by culture, polymerase chain reaction (PCR), and partial sequencing. Bartonella was isolated from 21 (20.4%) cats and detected by PCR from 20 (19.4%) cats, 2 (1.7%) dogs, 55 (39%) fleas collected from cats, 28 (10%) ticks DNA samples, and 1 (2.8%) flea collected from dogs. When combining culture and PCR data, 27 cats and 55 fleas collected on cats were positive for Bartonella henselae or Bartonella clarridgeiae, but none were coinfected. Approximately half of the B. henselae isolates from 21 cats were B. henselae type I. Moreover, B. henselae, Bartonella phoceensis, Bartonella queenslandensis, Bartonella rattimassiliensis, Bartonella elizabethae DNA was detected in ticks collected from dogs and one flea was B. clarridgeiae PCR positive. This is the first report of such a wide variety of Bartonella spp. detected in Rhipicephalus sanguineus. Further studies are required to understand the relative importance of these ectoparasites to transmit Bartonella spp. in dogs and cats.     

Rodent-associated Bartonella in Saskatchewan, Canada

Six species of wild rodents were sampled at 10 sites in 2002 and 2003 to determine the prevalence of Bartonella infections in rodent communities near Saskatoon, Saskatchewan, Canada. Isolates were characterized genotypically and compared with isolates found at other locations. Of 104 wild rodents examined, 57% were infected with Bartonella and prevalence within species varied from 49% for Richardson's ground squirrels (Spermophilus richardsonii) to 90% for Franklin's ground squirrels (S. franklinii). Infected rodents were found at all sites. Sequencing of a 379-bp portion of the citrate synthase gene was performed on 54 isolates and revealed 13 distinct genotypes, eight of which had not been described previously. The most common genotype detected in red-backed voles (Clethrionomys gapperi) was 99.1% similar to B. grahamii, a known human pathogen. Two of 10 Franklin's ground squirrels were concurrently infected with multiple Bartonella genotypes. All genotypes, with the exception of one detected in both Franklin's and thirteen-lined ground squirrels (S. tridecemlineatus), were found in only one host, and all genotypes from each species, with the exception of genotypes detected in red-backed voles, clustered together within the same relatedness group, suggesting that at least some Bartonella genotypes are specific to some rodent hosts.     

云南省泸西县啮齿动物携带立克次体调查

目的 调查云南省泸西县啮齿动物携带恙虫病东方体、无形体和埃立克体的状况,了解该类病原体在当地自然界中的保存状况和基因特征。方法 用鼠笼和鼠夹在云南省泸西县捕鼠,将捕获的动物种类鉴定后解剖取脾脏,活鼠取血。采用巢式PCR扩增脾脏的恙虫病东方体groEL基因,无形体和埃立克体的16S rRNA基因特异片段;测定PCR扩增阳性产物的DNA序列,对获得序列进行序列比对和系统进化分析。IFA法检测鼠血清中恙虫病东方体IgG抗体。结果 在泸西县共捕获啮齿动物10种225只。其中黄胸鼠36.89%(83/225)、大绒鼠35.11%(79/225)和中华姬鼠13.78%(31/225)为优势鼠种。获得鼠血清85份。鼠脾脏中检测到5株东方体groEL基因阳性标本,带毒鼠种为黄胸鼠2.41%(2/83)和大绒鼠3.80%(3/79)。同源性比较显示,这5株东方体的相似性在99.02%~100%之间,他们分别与GenBank中已知立克次体序列的相似性在98.75%~100%。系统发生树显示,5株OT与来自日本、泰国和中国安徽的菌株位于同一分支。3份16S rRNA阳性标本,其中1份埃立克体阳性,来源于大绒鼠;1份沃尔巴克氏体和1份巴尔通体阳性均来源于黄胸鼠。无形体均为阴性。埃立克体株序列比对显示与来自美国、中国和巴西的埃立克体基因同源性为98.0%~100%,并与分离自美国野外工作者皮肤的伊文氏埃立克体在同一分支。鼠血清恙虫病IgG抗体阳性7份,阳性率8.24%(7/85)。结论 该地区存在以黄胸鼠和大绒鼠为主要宿主的恙虫病自然疫源地。埃立克体、巴尔通体和沃尔巴克氏体在啮齿动物中也存在感染,需注意防控。     

High Prevalence of Rickettsia typhi and Bartonella Species in Rats and Fleas,Kisangani, Democratic Republic of the Congo

The prevalence and identity of Rickettsia and Bartonella in urban rat and flea populations were evaluated in Kisangani, Democratic Republic of the Congo (DRC) by molecular tools. An overall prevalence of 17% Bartonella species and 13% Rickettsia typhi, the agent of murine typhus, was found in the cosmopolitan rat species, Rattus rattus and Rattus norvegicus that were infested by a majority of Xenopsylla cheopis fleas. Bartonella queenslandensis, Bartonella elizabethae, and three Bartonella genotypes were identified by sequencing in rat specimens, mostly in R. rattus. Rickettsia typhi was detected in 72% of X. cheopis pools, the main vector and reservoir of this zoonotic pathogen. Co-infections were observed in rodents, suggesting a common mammalian host shared by R. typhi and Bartonella spp. Thus, both infections are endemic in DRC and the medical staffs need to be aware knowing the high prevalence of impoverished populations or immunocompromised inhabitants in this area.     

Ecological diversity of Bartonella species infection among dogs and their owner in Virginia

Bartonella species comprise a genus of gram-negative, fastidious, intracellular bacteria that have been implicated in association with an increasing spectrum of disease manifestations in dogs and human patients. In this study, chronic canine and human disease, for which causation was not diagnostically defined, were reported by the breeder of a kennel of Doberman pinschers. In addition to other diagnostic tests, serology, polymerase chain reaction, and enrichment blood culture were used to assess the prevalence of Bartonella sp. infection in the dogs and their owner. From five dogs, Bartonella vinsonii subsp. berkhoffii genotype I, multiple Bartonella henselae strains, and a species most similar to Candidatus B. volans, a rodent-associated Bartonella sp., were amplified and sequenced from biopsy tissues, cerebrospinal fluid, or blood enrichment cultures. The owner was bacteremic with B. vinsonii subsp. berkhoffii genotype I, the same subsp. and genotype detected in one of her dogs. These results further emphasize the ecological complexity of Bartonella sp. transmission in nature.     

Genetic and ecologic characteristics of Bartonella communities in rodents in southern China

Ecologic and bacteriologic observations of small mammals captured in Yunnan Province in the People's Republic of China indicated that Bartonella infections occurred at a high prevalence among some rodent species. Sequence analyses of the citrate synthase genes of these Bartonella demonstrated that rodents in this region harbored a diverse assemblage of strains. The Bartonella isolates obtained from Apodemus, Eothenomys, and Rattus typically clustered separately by genus of rodent host. Cultures obtained from Rattus rats were genetically related to Bartonella elizabethae, a recognized human pathogen. The finding of Bartonella species in a high proportion of the rodent samples from Yunnan suggests the need to investigate whether these agents might be responsible for cases of febrile illnesses of unknown etiology in southern China and elsewhere in southeastern Asia.     

Prevalence and Diversity of Bartonella spp. in Bats in Peru

Abstract. Bartonella infections were investigated in bats in the Amazon part of Peru. A total of 112 bats belonging to 19 species were surveyed. Bartonella bacteria were cultured from 24.1% of the bats (27/112). Infection rates ranged from 0% to 100% per bat species. Phylogenetic analyses of gltA of the Bartonella isolates revealed 21 genetic variants clustering into 13 divergent phylogroups. Some Bartonella strains were shared by bats of multiple species, and bats of some species were infected with multiple Bartonella strains, showing no evident specific Bartonella sp.-bat relationships. Rarely found in other bat species, the Bartonella strains of phylogroups I and III discovered from the common vampire bats (Desmodus rotundus) were more specific to the host bat species, suggesting some level of host specificity.     

Bartonella strains in small mammals from Dhaka, Bangladesh, related to Bartonella in America and Europe

Ecological and bacteriologic observations of small mammals captured in Dhaka, Bangladesh, indicated that Bartonella infections occurred in high prevalence among lesser bandicoot rats (Bandicota bengalensis), black rats (Rattus rattus), and house shrews (Suncus murinus). Sequence analysis of the citrate synthase gene of Bartonella isolates showed that small mammals in Bangladesh harbored a diverse assemblage of strains. Some cultures were genetically related to Bartonella elizabethae, a species identified from a human patient in the United States. Sequences of some other cultures from Bandicota and Rattus rats were identical to sequences of cultures from domestic rats in France, Portugal, and the United States. The finding of Bartonella species in a high proportion of the mammalian samples from Dhaka suggests the need to study whether these agents might be responsible for human cases of febrile illness of unknown etiology in Bangladesh and elsewhere in south Asia.