Prevalence of Bartonella sp. in United States military working dogs with infectious endocarditis: a retrospective case-control study.

OBJECTIVES: Bartonella infection has been associated with endocarditis in humans, dogs, cats and cattle. In order to evaluate the importance of this pathogen as a possible source of endocarditis in United States military working dogs (MWDs), we performed a retrospective case-control study on 26 dogs with histological diagnosis of culture negative endocarditis (n = 18), endomyocarditis (n = 5) or endocardiosis (n = 3) and 28 control dogs without any histological cardiac lesions. METHODS: DNA was extracted from paraffin embedded cardiac valves and tissues from case and control dogs and submitted to PCR testing with primers targeting the Bartonella gltA gene. PCR-RFLP using four restriction endonucleases and partial sequencing was then performed to determine the Bartonella species involved. RESULTS: Nineteen (73%) cases were PCR positive for Bartonella, including B. henselae (8 dogs), B. vinsonii subsp. berkhoffii (6 dogs), B. washoensis (2 dogs) and B. elizabethae (1 dog). Only one control dog was weakly PCR positive for Bartonella. Based on the type of histological diagnosis, 13 (72.2%) dogs with endocarditis, 3 (60%) dogs with endomyocarditis and all 3 dogs with endocardiosis were Bartonella PCR positive. CONCLUSIONS: Bartonella sp. Infections were correlated with cardiopathies in US military working dogs. Systemic use of insecticides against ectoparasites and regular testing of MWDs for Bartonella infection seem highly appropriate to prevent such life-threatening exposures.

Isolation of Bartonella henselae, Bartonella koehlerae subsp. koehlerae, Bartonella koehlerae subsp. bothieri and a new subspecies of B. koehlerae from free-ranging lions (Panthera leo) from South Africa, cheetahs (Acinonyx jubatus) from Namibia and captive cheetahs from California.

Bartonellae are blood- and vector-borne Gram-negative bacteria, recognized as emerging pathogens. Whole-blood samples were collected from 58 free-ranging lions (Panthera leo) in South Africa and 17 cheetahs (Acinonyx jubatus) from Namibia. Blood samples were also collected from 11 cheetahs (more than once for some of them) at the San Diego Wildlife Safari Park. Bacteria were isolated from the blood of three (5%) lions, one (6%) Namibian cheetah and eight (73%) cheetahs from California. The lion Bartonella isolates were identified as B. henselae (two isolates) and B. koehlerae subsp. koehlerae. The Namibian cheetah strain was close but distinct from isolates from North American wild felids and clustered between B. henselae and B. koehlerae. It should be considered as a new subspecies of B. koehlerae. All the Californian semi-captive cheetah isolates were different from B. henselae or B. koehlerae subsp. koehlerae and from the Namibian cheetah isolate. They were also distinct from the strains isolated from Californian mountain lions (Felis concolor) and clustered with strains of B. koehlerae subsp. bothieri isolated from free-ranging bobcats (Lynx rufus) in California. Therefore, it is likely that these captive cheetahs became infected by an indigenous strain for which bobcats are the natural reservoir.

Molecular epidemiology of Bartonella species isolated from ground squirrels and other rodents in northern California.

Bartonella spp. are endemic in wild rodents in many parts of the world. A study conducted in two northern California counties (Sonoma and Yolo) sampling California ground squirrels (Otospermophilus beecheyi) and four other rodent species (Peromyscus maniculatus, P. boylii, P. truei and Neotoma fuscipes) led to the isolation of small Gram-negative bacilli which were identified as Bartonella spp. based on colony morphology, polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and partial gene sequencing. Overall, Bartonella spp. were isolated from the blood of 71% (32/45) of the ground squirrels and one third (22/66) of the other rodents. PCR-RFLP analysis of the gltA and 16S rRNA genes yielded seven unique profiles, four for the ground squirrels and three for the other rodents. Isolates from each PCR-RFLP profiles were submitted for partial sequencing. Ground squirrel isolates were most closely related to B. washoensis, whereas the other rodent isolates were closest to B. vinsonii subsp. vinsonii and B. vinsonii subsp. arupensis. Two of these three species or subspecies are known zoonotic agents.

Bartonella clarridgeiae and Bartonella vinsonii subsp. berkhoffii exposure in captive wild canids in Brazil.

SUMMARY Wild canids are potential hosts for numerous species of Bartonella, yet little research has been done to quantify their infection rates in South America. We sought to investigate Bartonella seroprevalence in captive wild canids from 19 zoos in São Paulo and Mato Grosso states, Brazil. Blood samples were collected from 97 wild canids belonging to four different native species and three European wolves (Canis lupus). Indirect immunofluorescent antibody testing was performed to detect the presence of B. henselae, B. vinsonii subsp. berkhoffii, B. clarridgeiae, and B. rochalimae. Overall, Bartonella antibodies were detected in 11 of the canids, including five (12·8%) of 39 crab-eating foxes (Cerdocyon thous), three (11·1%) of 27 bush dogs (Speothos venaticus), two (8·7%) of 23 maned wolves (Chrysocyon brachyurus) and one (12·5%) of eight hoary foxes (Lycalopex vetulus), with titres ranging from 1:64 to 1:512. Knowing that many species of canids make excellent reservoir hosts for Bartonella, and that there is zoonotic potential for all Bartonella spp. tested for, it will be important to conduct further research in non-captive wild canids to gain an accurate understanding of Bartonella infection in free-ranging wild canids in South America.

Bartonella infection in urban and rural dogs from the tropics: Brazil, Colombia, Sri Lanka and Vietnam.

Dogs can be infected by a wide range of Bartonella spp., but limited studies have been conducted in tropical urban and rural dog populations. We aimed to determine Bartonella antibody prevalence in 455 domestic dogs from four tropical countries and detect Bartonella DNA in a subset of these dogs. Bartonella antibodies were detected in 38 (8·3%) dogs, including 26 (10·1%) from Colombia, nine (7·6%) from Brazil, three (5·1%) from Sri Lanka and none from Vietnam. DNA extraction was performed for 26 (63%) of the 41 seropositive and 10 seronegative dogs. Four seropositive dogs were PCR positive, including two Colombian dogs, infected with B. rochalimae and B. vinsonii subsp. berkhoffii, and two Sri Lankan dogs harbouring sequences identical to strain HMD described in dogs from Italy and Greece. This is the first detection of Bartonella infection in dogs from Colombia and Sri Lanka and identification of Bartonella strain HMD from Asia.

Experimental infection of horses with Bartonella henselae and Bartonella bovis.

BACKGROUND: Experimental infection of horses with Bartonella species is not documented. OBJECTIVES: Determine clinical signs, hematologic changes, duration of bacteremia, and pattern of seroconversion in Bartonella henselae or Bartonella bovis-inoculated horses. ANIMALS: Twelve (2 groups of 6) randomly selected healthy adult horses seronegative and culture negative for Bartonella spp. METHODS: Experimental/observational study: Group I: B. henselae or saline control was inoculated intradermally into 4 naïve and 2 sentinel horses, respectively. Group II: same design was followed by means of B. bovis. Daily physical examinations, once weekly CBC, immunofluorescent antibody assay serology, real-time polymerase chain reaction (PCR), and twice weekly blood cultures were performed for 6 weeks and at postinoculation day 80 and 139. Bartonella alpha-Proteobacteria growth medium (BAPGM) enrichment blood culture was performed for horses that seroconverted to B. henselae antigens. RESULTS: Transient clinical signs consistent with bartonellosis occurred in some Bartonella-inoculated horses, but hematological alterations did not occur. Three B. henselae-inoculated horses seroconverted, whereas 1 B. bovis-inoculated horse was weakly seropositive. In Group I, B. henselae was amplified and sequenced from BAPGM blood culture as well as a subculture isolate from 1 horse, blood from a 2nd horse, and BAPGM blood culture from a 3rd horse although a subculture isolate was not obtained. All sentinels remained PCR, culture, and serology negative. CONCLUSIONS: Detection of Bartonella sp. in blood after experimental inoculation supports bacteremia and seroconversion. Culture with BAPGM may be required to detect Bartonella sp. Although mild clinical signs followed acute infection, no long-term effects were noted for 2 years postinoculation.

Bartonellosis, an increasingly recognized zoonosis.

Cat scratch disease is the most common zoonotic infection caused by Bartonella bacteria. Among the many mammals infected with Bartonella spp., cats represent a large reservoir for human infection, as they are the main reservoir for Bartonella henselae, Bartonella clarridgeiae and Bartonella koehlerae. Bartonella spp. are vector-borne bacteria, and transmission of B. henselae by cat fleas occurs mainly through infected flea faeces, although new potential vectors (ticks and biting flies) have been identified. Dogs are also infected with various Bartonella species and share with humans many of the clinical signs induced by these infections. Although the role of dogs as source of human infection is not yet clearly established, they represent epidemiological sentinels for human exposure. Present knowledge on the aetiology, clinical features and epidemiological characteristics of bartonellosis is presented.

Bartonella endocarditis: a pathology shared by animal reservoirs and patients.

Bartonellae were first recognized to cause endocarditis in humans in 1993 when cases caused by Bartonella quintana, B. elizabethae, and B. henselae were reported. Since the first isolation of Bartonella vinsonii subspecies berkhoffii from a dog with endocarditis, this organism has emerged as an important pathogen in dogs and an emerging pathogen in people. Subsequently, four types of B. vinsonii subsp. berkhoffii have been described, all of which have been associated with endocarditis in dogs. A limited number of dog endocarditis cases have also been associated with B. clarridgeiae, B. washoensis, B. quintana, and B. rochalimae. The second canine B. clarridgeiae endocarditis case is presented. The clinical and pathological characteristics of Bartonella endocarditis in dogs are similar to disease observed in humans, more often affecting the aortic valve, presenting with highly vegetative lesions with accompanying calcification, and in most instances high antibody titers. Pathological features in dogs include a combination of fibrosis, mineralization, endothelial proliferation, and neovascularization with variable inflammation. Endocarditis has also been described in animal species, which are the natural reservoir of specific Bartonella species, once thought to be solely healthy carriers of these pathogens. A few Bartonella endocarditis cases, including B. henselae, have been reported in cats in the USA and Australia. The second case of B. henselae type Houston I identified in the USA is presented. Furthermore, two cases of B. bovis endocarditis were recently described in adult cows from France. Finally, on-going investigation of valvular endocarditis in free-ranging Alaskan sea otters suggests the involvement of Bartonella species.

Environmental factors associated with Bartonella vinsonii subsp. berkhoffii seropositivity in free-ranging coyotes from northern California.

Bartonella vinsonii subsp. berkhoffii is a newly recognized pathogen of domestic dogs and humans. Coyotes (Canis latrans) are considered an important reservoir of this bacterium in the western United States, but its vectors are still unknown. Our objective was to identify environmental factors associated with Bartonella antibody prevalence in 239 coyotes from northern California, using an enzyme-linked immunosorbent assay. In addition, associations were evaluated between B. v. berkhoffii and two pathogens with known vectors and habitat requirements, Dirofilaria immitis and Anaplasma phagocytophilum. Overall, B. v. berkhoffii seroprevalence was 28% (95% confidence interval [CI], 22.3%, 33.7%) and Bartonella seropositive coyotes were more likely than seronegative coyotes to be positive for Anaplasma phagocytophilum (Odds ratio = 3.3; 95% CI = 1.8, 5.9) and Dirofilaria immitis (Odds ratio = 2.1; 95% CI = 1.2, 3.8). The most likely geographic clusters of Bartonella and Dirofilaria overlapped. Bartonella seropositivity was associated with higher precipitation (p = 0.003) and proximity to the coast (p = 0.007) in univariate analysis. The association with precipitation varied with season, based on a logistic regression model.

Pathology of bartonella endocarditis in six dogs.

In a 5-year retrospective study of dogs presenting to the Veterinary Medical Teaching Hospital at the University of California, Davis, there were 31 histologic diagnoses of valvular endocarditis. By polymerase chain reaction (PCR) amplification of embedded valvular tissue, Bartonella organisms were exclusively associated with 6 out of 31 cases (19%). Confirmed Bartonella cases involved the aortic valve alone (five out of six) or in combination with the mitral valve (one of six). Microscopic features of Bartonella endocarditis were compared with valves from non-Bartonella endocarditis and with valvular change unrelated to infectious agents (endocardiosis). Features of Bartonella endocarditis included a combination of fibrosis, mineralization, endothelial proliferation, and neovascularization with variable inflammation. None of these features is specific; however, the combination is distinct both from endocarditis caused by culturable bacteria and from endocardiosis. Ultrastructural analyses revealed both extracellular and intraendothelial bacteria. Clinical history, serology, and PCR are currently necessary to establish an etiologic diagnosis of Bartonella endocarditis.

Serosurvey of selected zoonotic agents in polar bears (Ursus maritimus).

Between 1982 and 1999 blood samples were collected from 500 polar bears (Ursus maritimus) captured in the Beaufort and Chukchi seas, to determine the seroprevalence of Brucella species, Toxoplasma gondii, and Trichinella species infections. The bears were classified into four age groups, cubs, yearlings, subadults and adults. Brucella and Toxoplasma antibodies were detected by agglutination (a buffered acidified card antigen and rapid automated presumptive test for brucellosis and a commercial latex agglutination test for toxoplasmosis); an ELISA was used to detect Trichinella antibodies. The overall seroprevalence of Brucella species was 5 per cent, and subadults and yearlings were 2-62 times (95 per cent confidence interval 1.02 to 6.82) more likely to be seropositive for Brucella species than adults and their cubs. The antibody prevalence for Toxoplasma gondii was 6 per cent, and for Trichinella species 55.6 per cent. The prevalence of antibodies to Trichinella species increased with age (P<0.001).

Prevalence of Bartonella infection in wild African lions (Panthera leo) and cheetahs (Acinonyx jubatus).

Bartonella species are emerging pathogens that have been isolated worldwide from humans and other mammals. Our objective was to estimate the prevalence of Bartonella infection in free-ranging African lions (Panthera leo) and cheetahs (Acinonyx jubatus). Blood and/or serum samples were collected from a convenience sample of 113 lions and 74 cheetahs captured in Africa between 1982 and 2002. Whole blood samples available from 58 of the lions and 17 of the cheetahs were cultured for evidence of Bartonella spp., and whole blood from 54 of the 58 lions and 73 of the 74 cheetahs tested for the presence of Bartonella DNA by TaqMan PCR. Serum samples from the 113 lions and 74 cheetahs were tested for the presence of antibodies against Bartonella henselae using an immunofluorescence assay. Three (5.2%) of the 58 lions and one (5.9%) of the 17 cheetahs were bacteremic. Two lions were infected with B. henselae, based on PCR/RFLP of the citrate synthase gene. The third lion and the cheetah were infected with previously unidentified Bartonella strains. Twenty-three percent of the 73 cheetahs and 3.7% of the 54 lions tested by TaqMan PCR were positive for Bartonella spp. B. henselae antibody prevalence was 17% (19/113) for the lions and 31% (23/74) for the cheetahs. The prevalence of seropositivity, bacteremia, and positive TaqMan PCR was not significantly different between sexes and age categories (juvenile versus adult) for both lions and cheetahs. Domestic cats are thus no longer the only known carriers of Bartonella spp. in Africa. Translocation of B. henselae seronegative and TaqMan PCR negative wild felids might be effective in limiting the spread of Bartonella infection.

Validation for use with coyotes (Canis latrans) of a commercially available enzyme-linked immunosorbent assay for Dirofilaria immitis.

Serological tests offer a potentially powerful tool for monitoring parasites in wildlife populations. However, such tests must be validated before using them with target wildlife populations. We evaluated in coyotes (Canis latrans) the performance of a commercially available serological test used to detect canine heartworm (Dirofilaria immitis) in domestic dogs. We obtained 265 coyote carcasses and serological specimens from 54 additional coyotes from several regions of California, USA. We necropsied coyotes to determine the adult heartworm infection status. Blood was collected at necropsy on filter paper strips and allowed to dry; it was later eluted in a buffer solution, and the supernatant was tested for heartworm. Receiver operating characteristic (ROC) analysis was used to assess discriminatory power of the test and indicated a 93% probability that a randomly selected infected coyote would exhibit a higher enzyme-linked immunosorbent assay (ELISA) value than a randomly selected uninfected coyote. We estimated specificity at 96% (95% CI: 92-98%) for 165 uninfected coyotes and sensitivity at 85% (77-91%) for 100 infected coyotes, results similar to published values for the commercial serological test used with dog serum or plasma. Test performance was similar for filter paper specimens and supernatant of frozen whole blood collected in EDTA tubes (i.e. hemolyzed plasma). We found no difference in test performance among geographic or demographic coyote groups. Our findings support application of the test to filter paper or standard serological specimens for detection of heartworm in coyote populations.

Aortic valve endocarditis in a dog due to Bartonella clarridgeiae.

We report the first documented case of endocarditis associated with Bartonella clarridgeiae in any species. B. clarridgeiae was identified as a possible etiological agent of human cat scratch disease. Infective vegetative valvular aortic endocarditis was diagnosed in a 2.5-year-old male neutered boxer. Historically, the dog had been diagnosed with a systolic murmur at 16 months of age and underwent balloon valvuloplasty for severe valvular aortic stenosis. Six months later, the dog was brought to a veterinary hospital with an acute third-degree atrioventricular block and was diagnosed with infective endocarditis. The dog died of cardiopulmonary arrest prior to pacemaker implantation. Necropsy confirmed severe aortic vegetative endocarditis. Blood culture grew a fastidious, gram-negative organism 8 days after being plated. Phenotypic and genotypic characterization of the isolate, including partial sequencing of the citrate synthase (gltA) and 16S rRNA genes indicated that this organism was B. clarridgeiae. DNA extraction from the deformed aortic valve and the healthy pulmonic valve revealed the presence of B. clarridgeiae DNA only from the diseased valve. No Borrelia burgdorferi or Ehrlichia sp. DNA could be identified. Using indirect immunofluorescence tests, the dog was seropositive for B. clarridgeiae and had antibodies against Ehrlichia phagocytophila but not against Ehrlichia canis, Ehrlichia ewingii, B. burgdorferi, or Coxiella burnetii.

Molecular evidence of Bartonella spp. in questing adult Ixodes pacificus ticks in California.

Ticks are the vectors of many zoonotic diseases in the United States, including Lyme disease, human monocytic and granulocytic ehrlichioses, and Rocky Mountain spotted fever. Most known Bartonella species are arthropod borne. Therefore, it is important to determine if some Bartonella species, which are emerging pathogens, could be carried or transmitted by ticks. In this study, adult Ixodes pacificus ticks were collected by flagging vegetation in three sites in Santa Clara County, Calif. PCR-restriction fragment length polymorphism and partial sequencing of 273 bp of the gltA gene were applied for Bartonella identification. Twenty-nine (19.2%) of 151 individually tested ticks were PCR positive for Bartonella. Male ticks were more likely to be infected with Bartonella than female ticks (26 versus 12%, P = 0.05). None of the nine ticks collected at Baird Ranch was PCR positive for Bartonella. However, 7 (50%) of 14 ticks from Red Fern Ranch and 22 (17%) of 128 ticks from the Windy Hill Open Space Reserve were infected with Bartonella. In these infected ticks, molecular analysis showed a variety of Bartonella strains, which were closely related to a cattle Bartonella strain and to several known human-pathogenic Bartonella species and subspecies: Bartonella henselae, B. quintana, B. washoensis, and B. vinsonii subsp. berkhoffii. These findings indicate that I. pacificus ticks may play an important role in Bartonella transmission among animals and humans.

Epidemiology of Bartonella infection in domestic cats in France.

Blood samples were collected between February and June 1996 from a convenience sample of 436 domestic French cats living in Paris and its environs and were tested for Bartonella bacteremia and seropositivity. Seventy-two cats (16.5%) were Bartonella bacteremic, of which 36 cats (50%) were infected with Bartonella henselae type II (B.h. II) only, 15 cats (21%) were infected with Bartonella clarridgeiae (B.c.) only, and 11 cats (15%) were infected with B. henselae type I (B.h. I) only. Eight cats (11%) were co-infected with B. henselae and B. clarridgeiae (B.h. II/B.c.: five cats; B.h. I/B.c.: three cats). Two cats (2.8%) were concurrently bacteremic with B. henselae types I and II. Risk factors associated with bacteremia included ownership for <6months (prevalence ratio (PR)=1.80; 95% confidence interval (CI)=1.13-2.85), adoption from the pound or found as a stray (PR=1.67, 95% CI=1.05-2.65), and cohabitation with one or more cats (PR=1.60, 95% CI=1.01-2.53). Bartonella antibodies to either B. henselae or B. clarridgeiae were detected in 179 cats (41.1%). Risk factors associated with seroposivity paralleled those for bacteremia, except for lack of association with time of ownership. Prevalence ratios of bacteremic or seropositive cats increased with the number of cats per household (p=0.02). The lack of antibodies to B. henselae or B. clarridgeiae was highly predictive of the absence of bacteremia (predictive value of a negative test=97.3%). Multiple logistic regression analysis indicated that bacteremia, after adjustment for age and flea infestation, and positive serology, after adjustment for age, were associated with origin of adoption and number of cats in the household. Flea infestation was associated with positive serology.

Genomic diversity of Bartonella henselae isolates from domestic cats from Japan, the USA and France by pulsed-field gel electrophoresis.

The genomic DNA diversity of 27 Bartonella henselae and three B. clarridgeiae isolates from 18 domestic cats from Japan, the USA and France was investigated by pulsed-field gel electrophoresis (PFGE) with NotI, AscI and SmaI restriction enzymes. A great diversity of genomic patterns was found for all B. henselae, but none for B. clarridgeiae isolates. The DNA size of B. henselae and B. clarridgeiae isolates were 1.7-2.9 and 1.7Mbp, respectively. All 13 Japanese cat isolates were identified as B. henselae type I. Furthermore, three of the four Japanese cats harbored genetically different B. henselae type I isolates, suggesting for the first time co-infection with various type I isolates. One French cat and one American cat were co-infected with B. henselae and B. clarridgeiae. B. henselae type I and type II were mainly grouped in two different clusters by PFGE using SmaI endonuclease in the dendrogram.

Prevalence of Bartonella species and 16s rRNA gene types of Bartonella henselae from domestic cats in Thailand.

Prevalence of Bartonella infection among 275 cats in 9 sites from 4 geographical regions (northern area: Chiang Mai; central area: Kanchanaburi, Ratchaburi, and Bangkok; northeastern area: Khon Kaen, Roi Et, Ubon Ratcharthani, and Nakhonratchasima; southern area: Songkhla) of Thailand was investigated. Overall, Bartonella species were isolated from 27.6% (76 of 275) of the cats. The isolation rate varied from 12.8% (5 of 39) in Songkhla (southern area) to 50.0% (26 of 52) in Khon Kaen (northeastern area). Bartonella henselae and B. clarridgeiae were isolated from 82.9% (63 of 76) and 11.8% (9 of 76) of the Bartonella-positive cats, respectively. Coinfection with both species was found in 5.3% (4 of 76) of the bacteremic cats. Of the 67 bacteremic cats from which B. henselae was isolated, 48 (71.6%) and 13 (19.4%) were infected with only Type I and Type II, respectively. Coinfection with both types was observed in 9.0% (6 of 67) of the B. henselae-positive cats. To our knowledge, this is the first report on the presence of Bartonella infection in domestic cats from Thailand, which constitute a large reservoir of Bartonella infection in this country.

Coyotes (Canis latrans) as the reservoir for a human pathogenic Bartonella sp.: molecular epidemiology of Bartonella vinsonii subsp. berkhoffii infection in coyotes from central coastal California.

Bartonella vinsonii subsp. berkhoffii was originally isolated from a dog suffering infectious endocarditis and was recently identified as a zoonotic agent causing human endocarditis. Following the coyote bite of a child who developed clinical signs compatible with Bartonella infection in Santa Clara County, Calif., this epidemiological study was conducted. Among 109 coyotes (Canis latrans) from central coastal California, 31 animals (28%) were found to be bacteremic with B. vinsonii subsp. berkhoffii and 83 animals (76%) had B. vinsonii subsp. berkhoffii antibodies. These findings suggest these animals could be the wildlife reservoir of B. vinsonii subsp. berkhoffii. PCR-restriction fragment length polymorphism (PCR-RFLP) analysis of the gltA and 16S rRNA genes for these 31 isolates yielded similar profiles that were identical to those of B. vinsonii subsp. berkhoffii. Partial sequencing of the gltA and 16S rRNA genes, respectively, indicated 99.5 and 100% homology between the coyote isolate and B. vinsonii subsp. berkhoffii (ATCC 51672). PCR-RFLP analysis of the 16S-23S intergenic spacer region showed the existence of two different strain profiles, as has been reported in dogs. Six (19%) of 31 Bartonella bacteremic coyotes exhibited the strain profile that was identified in the type strain of a canine endocarditis case (B. vinsonii subsp. berkhoffii ATCC 51672). The other 25 bacteremic coyotes were infected with a strain that was similar to the strains isolated from healthy dogs. Based on whole bacterial genome analysis by pulsed-field gel electrophoresis (PFGE) with SmaI restriction endonuclease, there was more diversity in fingerprints for the coyote isolates, which had at least 10 major variants compared to the two variants described for domestic dog isolates from the eastern United States. By PFGE analysis, three Bartonella bacteremic coyotes were infected by a strain identical to the one isolated from three healthy dog carriers. Further studies are necessary to elucidate the mode of transmission of B. vinsonii subsp. berkhoffii, especially to identify potential vectors, and to determine how humans become infected.

Bartonella spp. isolated from wild and domestic ruminants in North America.

Bartonella species were isolated from 49% of 128 cattle from California and Oklahoma, 90% of 42 mule deer from California, and 15% of 100 elk from California and Oregon. Isolates from all 63 cattle, 14 deer, and 1 elk had the same polymerase chain reaction/restriction fragment length polymorphism profiles. Our findings indicate potential for inter- and intraspecies transmission among ruminants, as well as risk that these Bartonella spp. could act as zoonotic agents.