Prevalence of Bartonella henselae in stray and domestic cats in different Italian areas: evaluation of the potential risk of transmission of Bartonella to humans

Bartonella henselae is the major etiological agent of Cat Scratch Disease in humans. Cats act as the natural reservoir of B. henselae and can transmit the infection to humans by bite or scratch. The diffusion of B. henselae was evaluated by seroprevalence and bacteremic status in different stray cat populations located in nine areas of Northern Italy. A total of 1585 cats were tested by blood culture and 361 (23%) resulted bacteremic; 1416 out off 1585 cats were also tested for Bartonella henselae antibodies and 553 (39%) resulted seropositive. The molecular typing of the isolates showed that 26% of bacteremic cats were infected with B. henselae type I, 52% with B. henselae type II, 16% were co-infected with both and 5% infected with B. Clarridgeiae. Moreover 165 domestic cats were tested by blood culture and serological test (IFA test cut-off: 1:64). 35 cats (21%) resulted bacteremic and 49 (43.5%) were seropositive. The molecular typing of the Bartonella isolates of the domestic cats showed that 45% of bacteremic cats were infected with B. henselae type I, 36.5% with B. henselae type II, 12% were coinfected with both and 6% infected with B. Clarridgeiae. For a completely evaluation of health status of the cat for B. henselae infection, the authors suggest both blood culture and serological tests. Nevertheless a nonbacteremic cat with positive serology result should be reevaluated for possible recurrent bacteremia.     

Antibodies to Rickettsia rickettsii, Rickettsia typhi, Coxiella burnetii, Bartonella henselae, Bartonella quintana, and Ehrlichia chaffeensis among healthy population in Minas Gerais, Brazil

Rickettsial diseases except those belonging to spotted fever group rickettsioses are poorly studied in South America particularly in Brazil where few epidemiological reports have been published. We describe a serosurvey for Rickettsia rickettsii, R. typhi, Coxiella burnetii, Bartonella henselae, B. quintana, and Ehrlichia chaffeensis in 437 healthy people from a Brazilian rural community. The serum samples were tested by indirected micro-immunoflourescence technique and a cutoff titer of 1:64 was used. The seroprevalence rates for R. rickettsii, R. typhi, C. burnetii, B. henselae, B. quintana, and E. chaffeensis were respectively 1.6% (7 samples); 1.1% (5 samples); 3.9% (17 samples); 13.7% (60 samples); 12.8% (56 samples), and 10.5% (46 samples). Frequent multiple/cross-reactivity was observed in this study. Age over 40 years old, urban profession, and rural residence were significantly associated with some but not all infections rate. Low seropositivity rates for R. rickettsii, R. typhi, and C. burnetii contrasted with higher rates of seropositivity for B. quintana, B. henselae, and E. chaffeensis. These results show that all tested rickettsial species or antigenically closely related possible exist in this particular region.     

Seroimmunologic monitoring of microorganisms of Rickettsia and Bartonella species microorganisms in the Moscow region

Serological study of 788 blood sera, taken from residents of the Moscow region was conducted using antigens of microorganisms of the genera Rickettsia and Bartonella. The first group under examination consisted of 355 patients with diagnosed diseases of nonreckettsial nature. The second group includes 433 healthy adults working at a meat processing and packing factory. The main method used for sera survey was the indirect immunofluorescence test. In the sera taken from the first group of subjects specific antibodies to R. prowazekii, R. typhi, B. quintana, B. henselae antigens were detected in 2.3%, 5.1%, 4.0% and 2.9% of serum samples respectively. In the serum samples taken from the second group the proportion of antibodies to R. prowazekii, R. typhi, B. quintana, B. henselae antigens was different: 0.5%, 3.3%, 1.7% and 4.0% respectively. In total, specific antibodies to R. typhi and B. henselae prevailed over specific antibodies to R. prowazekii and B. quintana twofold.     

First evidence of feline herpesvirus, calicivirus, parvovirus, and Ehrlichia exposure in Brazilian free-ranging felids

Serum samples from 18 pumas (Puma concolor), one ocelot (Leopardus pardalis), and two little spotted cats (Leopardus tigrinus) collected from free-ranging animals in Brazil between 1998 and 2004 were tested by indirect immunofluorescence (IFA) for antibodies to feline herpesvirus 1 (FHV 1), calicivirus (FCV), coronavirus (FCoV), parvo-virus (FPV), Ehrlichia canis, Anaplasma pha-gocytophilum, and Bartonella henselae. Serum samples also were tested, by Western blot and ELISA, for feline leukemia virus (FeLV) specific antibodies and antigen, respectively, by Western blot for antibodies to feline immunodeficiency virus (FIV), and by indirect ELISA for antibodies to puma lentivirus (PLV). Antibodies to FHV 1, FCV, FCoV, FPV, FeLV, FIV, PLV or related viruses, and to B. henselae were detected. Furthermore, high-titered antibodies to E. canis or a closely related agent were detected in a puma for the first time.     

Isolation of Bartonella henselae from domestic cats in an Italian urban area

Bartonella henselae is the causative agent of Cat Scratch Disease (CSD) in humans. Cat is considered the reservoir of the bacterium. Identification of bacteriemic cats is the basic tool in the prophylaxis of CSD. Blood samples were collected between January 1999-December 2000 from 248 domestic cats living in an urban area (Reggio Emilia) in Northern Italy and tested for Bartonella henselae bacteriemia. Cultural and PCR methods were used. PCR was used directly on cat blood as well as to identify the Bartonella strain growth in culture. 24 (9.7 %) cats were found bacteriemic, most of which aged <1 year. A higher sensitivity was demonstrated by cultural method compared with PCR.     

Characterization of the genome composition of Bartonella koehlerae by microarray comparative genomic hybridization profiling

Bartonella henselae is present in a wide range of wild and domestic feline hosts and causes cat-scratch disease and bacillary angiomatosis in humans. We have estimated here the gene content of Bartonella koehlerae, a novel species isolated from cats that was recently identified as an agent of human endocarditis. The investigation was accomplished by comparative genomic hybridization (CGH) to a microarray constructed from the sequenced 1.93-Mb genome of B. henselae. Control hybridizations of labeled DNA from the human pathogen Bartonella quintana with a reduced genome of 1.58 Mb were performed to evaluate the accuracy of the array for genes with known levels of sequence divergence. Genome size estimates of B. koehlerae by pulsed-field gel electrophoresis matched that calculated by the CGH, indicating a genome of 1.7 to 1.8 Mb with few unique genes. As in B. quintana, sequences in the prophage and the genomic islands were reported absent in B. koehlerae. In addition, sequence variability was recorded in the chromosome II-like region, where B. koehlerae showed an intermediate retention pattern of both coding and noncoding sequences. Although most of the genes missing in B. koehlerae are also absent from B. quintana, its phylogenetic placement near B. henselae suggests independent deletion events, indicating that host specificity is not solely attributed to genes in the genomic islands. Rather, the results underscore the instability of the genomic islands even within bacterial populations adapted to the same host-vector system, as in the case of B. henselae and B. koehlerae.     

Population Structure of Bartonella henselae in Algerian Urban Stray Cats

Whole blood samples from 211 stray cats from Algiers, Algeria, were cultured to detect the presence of Bartonella species and to evaluate the genetic diversity of B. henselae strains by multiple locus VNTR analysis (MLVA). Bartonella henselae was the only species isolated from 36 (17%) of 211 cats. B. henselae genotype I was the predominant genotype (64%). MLVA typing of 259 strains from 30 bacteremic cats revealed 52 different profiles as compared to only 3 profiles using MLST. Of these 52 profiles, 48 (92.3%) were identified for the first time. One-third of the cats harbored one MLVA profile only. As there was a correlation between the age of cats and the number of MLVA profiles, we hypothesized that the single profile in these cats was the profile of the initial infecting strain. Two-third of the cats harbored 2 to 6 MLVA profiles simultaneously. The similarity of MLVA profiles obtained from the same cat, neighbor-joining clustering and structure-neighbor clustering indicate that such a diversity likely results from two different mechanisms occurring either independently or simultaneously: independent infections and genetic drift from a primary strain.     

巴尔通体液体培养条件简化及生长曲线观察

【目的】应用一种昆虫细胞培养基作为基础成分培养巴尔通体(Bartonella species),建立一种操作方便、高效稳定的巴尔通体液体培养方法。【方法】昆虫细胞培养基中添加10%胎牛血清,以此为基础培养液分别添加蔗糖和谷氨酰胺,比较这两种成分对汉赛巴尔通体(B.henselae)和五日热巴尔通体(B.quintana)生长的影响并观察其他10种巴尔通体在简化后的培养液中的生长特性。【结果】添加蔗糖和谷氨酰胺不会明显促进巴尔通体的生长,10种巴尔通体在简化后的培养液中均生长良好。不同种巴尔通体生长曲线不同,汉赛巴尔通体和五日热巴尔通体的世代时间分别为5.2 h和4.3 h,生长速度快于固体培养。【结论】以昆虫细胞培养基作为基础成分的培养液适于巴尔通体液体培养,特别是对一些更难培养的巴尔通体提供了一种较好的培养方法。     

Detection of the Bartonella DNA by the method of nested PCR in patients after tick bites in Novosibirsk region

Arthropod-borne bacterial pathogen Bartonella DNA was detected in human blood cells after tick bites in summer 2003 and 2004 in Novosibirsk region by nested PCR with primers specific to groEL gene of HSP60 protein. Comparative assay of 190 p.b. of long PCR fragment revealed that the nucleotide sequences might belong to Bartonella henselae and Bartonella quintana.     

P26-based serodiagnosis for Bartonella spp. infection in cats

Bartonella henselae P26 has been identified as an immunodominant antigen expressed during feline infection. We used antisera from cats experimentally infected with B. henselae (n = 6), B. clarridgeiae (n = 4), or B. koehlerae (n = 2) and from a sample of naturally infected cats (B. henselae, n = 34; B. clarridgeiae, n = 1) to evaluate recombinant P26 (rP26) as a serodiagnostic antigen. Immunoblots using antisera from cats infected with B. henselae and B. clarridgeiae reacted strongly with rP26, whereas B. koehlerae antisera did not. A capture ELISA was designed to evaluate the kinetics of rP26 IgG in sera from experimentally infected cats. For B. henselae and B. clarridgeiae antisera, the kinetic profiles of reactivity were similar for rP26 capture ELISA and Bartonella spp. indirect fluorescence assay. However, for B. koehlerae antisera, reactivity in rP26 capture ELISA was consistently low. The serodiagnostic potential of rP26 capture ELISA was evaluated using sera from cats with known Bartonella sp. exposure histories. All 24 (100%) uninfected cats were seronegative, and 33 of 35 (94.3%) cats bacteremic for Bartonella spp. were seropositive. We propose that rP26-based serology can serve as a useful adjunct tool for the diagnosis of feline infection with B. henselae and B. clarridgeiae, but it may not be useful for feline infection with B. koehlerae.     

Prevalence of Rickettsia and Bartonella species in Spanish cats and their fleas

The aim of this study was to determine the prevalence of Bartonella henselae, Rickettsia felis, and Rickettsia typhi in fleas and companion cats (serum and claws) and to assess their presence as a function of host, host habitat, and level of parasitism. Eighty‐nine serum and claw samples and 90 flea pools were collected. Cat sera were assayed by IFA for Bartonella henselae and Rickettssia species IgG antibodies. Conventional PCRs were performed on DNA extracted from nails and fleas collected from cats. A large portion (55.8%) of the feline population sampled was exposed to at least one of the three tested vector‐borne pathogens. Seroreactivity to B. henselae was found in 50% of the feline studied population, and to R. felis in 16.3%. R. typhi antibodies were not found in any cat. No Bartonella sp. DNA was amplified from the claws. Flea samples from 41 cats (46%) showed molecular evidence for at least one pathogen; our study demonstrated a prevalence rate of 43.3 % of Rickettsia sp and 4.4% of Bartonella sp. in the studied flea population. None of the risk factors studied (cat's features, host habitat, and level of parasitation) was associated with either the serology or the PCR results for Bartonella sp. and Rickettsia sp.. Flea‐associated infectious agents are common in cats and fleas and support the recommendation that stringent flea control should be maintained on cats.     

Bacteriological and molecular identification of Bartonella species in cats from different regions of China

With the improvements in diagnostic techniques, Bartonella henselae (B. henselae) infection has recently been recognized to cause a widening spectrum of diseases. Cats are the natural reservoir hosts of B. henselae. The current study aims to investigate the prevalence of B. henselae infection in the cat populations in China. Polymerase chain reaction (PCR) and bacterial cultures confirm that 12.7% of the tested cats were positive for the infection. Old age and outdoor exposure were statistically associated with the infection. Multilocus sequence typing and eBURST analysis of the cat isolates collected in the present study show that 65.4% of the isolates belong to sequence type 1 (ST1). Three new STs (ST16-18) were identified in Midwestern China. These results may aid our understanding of the population structure of B. henselae in China and the relationship between human and cat strains in subsequent studies.     

Anaplasma phagocytophilum infection in a fallow deer (Dama dama) population in a preserve of central Italy

From autumn 2004 to spring 2005, 70 fallow deer (Dama dama), 27 female and 43 male, living in a natural preserve of central Italy were examined by indirect immunofluorescence assay (IFA) to detect specific antibodies to Anaplasma phagocytophilum. Thirty-one (44.28%) sera scored positive: in particular 10 fallow deer (8 male and 2 female) scored positive at 40 antibody titer, 21 deer (8 male and 13 female) at > or = 80 titer. EDTA anticoagulated blood samples collected from 29 of the 70 deer examined were tested by a nested-PCR assay to disclose a 546 bp fragment, specific of A. phagocytophilum 16S rRNA gene. Twenty (72.41%) blood samples (8 male and 13 female deer) resulted positive. Fifteen PCR-positive deer also resulted positive to IFA, whereas the remaining six did not show specific antibodies. Three serologically positive animals gave negative results at the nested PCR. Five deer scored negative both to serological tests and PCR.     

Human bartonellosis: seroepidemiological and clinical features with an emphasis on data from Brazil - a review

Bartonellae are fastidious Gram-negative bacteria that are widespread in nature with several animal reservoirs (mainly cats, dogs, and rodents) and insect vectors (mainly fleas, sandflies, and human lice). Thirteen species or subspecies of Bartonella have been recognized as agents causing human disease, including B. bacilliformis, B. quintana, B. vinsonii berkhoffii, B. henselae, B. elizabethae, B. grahamii, B. washoensis, B. koehlerae, B. rocha-limaea, and B. tamiae. The clinical spectrum of infection includes lymphadenopathy, fever of unknown origin, endocarditis, neurological and ophthalmological syndromes, Carrion's disease, and others. This review provides updated information on clinical manifestations and seroepidemiological studies with an emphasis on data available from Brazil.     

Does Coinfection of Bartonella henselae and FIV Induce Clinical Disorders in Cats?

It was found that Bartonella henselae (B. henselae) may induce clinical disorders in cats in natural conditions from a comparison of the serological status for B. henselae with the serostatus for feline immunodeficiency virus (FIV) and several clinical characteristics in 170 domestic cats. Seropositivity for B. henselae was not significantly different between FIV antibody-positive and -negative cats (18.4% vs 16.0%). The incidence of clinical characteristics were compared among four cat groups distinguished by the reactivity of sera against B. henselae and FIV. The incidence of lymph node swelling was lower in only FIV antibody-positive cats (3.0%), but higher in B. henselae antibody-positive cats (13.6%) and significantly higher in both B. henselae and FIV antibody-positive cats (42.9%) compared with the incidence of lymph node swelling in cats which were negative for both antibodies (5.5%). The same relation was also observed for the incidence of gingivitis among the 4 cat groups, suggesting that coinfection of B. henselae and FIV may be associated with gingivitis and lymphadenopathy in cats.     

Prevalence of Bartonella henselae and Bartonella clarridgeiae in cats in the south of Brazil: a molecular study

Bartonella spp are the causative agent of cat scratch disease in humans. Cats are the natural reservoir of these bacteria and may infect humans through scratches, bites or fleas. Blood samples from 47 cats aged up to 12 months were collected for this study. All animals were lodged in municipal animal shelters in the Vale do Sinos region, Rio Grande do Sul, Brazil. Bartonella spp were detected by genus-specific polymerase chain reaction (PCR) and when the PCR was positive, the species were determined by DNA sequencing. A Giemsa-stained blood smear was also examined for the presence of intraerythrocytic elements suggestive of Bartonella spp infection. Phylogenetic analysis was also performed for all positive samples. Using molecular detection methods, Bartonella spp were detected in 17.02% (8/47) of the samples. In seven out of eight samples confirmed to be positive for Bartonella spp, blood smear examination revealed the presence of intraerythrocytic elements suggestive of Bartonella spp. Phylogenetic analysis characterized positive samples as Bartonella henselae (5) or Bartonella clarridgeiae (3). To the best of our knowledge, this is the first molecular study demonstrating the presence of Bartonella spp in cats from the Southern Region of Brazil.     

A genome-wide study of recombination rate variation in Bartonella henselae

ABSTRACT: BACKGROUND: Rates of recombination vary by three orders of magnitude in bacteria but the reasons for this variation is unclear. We performed a genome-wide study of recombination rate variation among genes in the intracellular bacterium Bartonella henselae, which has among the lowest estimated ratio of recombination relative to mutation in prokaryotes. RESULTS: The 1.9 Mb genomes of B. henselae strains IC11, UGA10 and Houston-1 genomes showed only minor gene content variation. Nucleotide sequence divergence levels were less than 1% and the relative rate of recombination to mutation was estimated to 1.1 for the genome overall. Four to eight segments per genome presented significantly enhanced divergences, the most pronounced of which were the virB and trw gene clusters for type IV secretion systems that play essential roles in the infection process. Consistently, multiple recombination events were identified inside these gene clusters. High recombination frequencies were also observed for a gene putatively involved in iron metabolism. A phylogenetic study of this gene in 80 strains of Bartonella quintana, B. henselae and B. grahamii indicated different population structures for each species and revealed horizontal gene transfers across Bartonella species with different host preferences. CONCLUSIONS: Our analysis has shown little novel gene acquisition in B. henselae, indicative of a closed pan-genome, but higher recombination frequencies within the population than previously estimated. We propose that the dramatically increased fixation rate for recombination events at gene clusters for type IV secretion systems is driven by selection for sequence variability.     

Bartonella henselae, B. quintana, and B. bacilliformis: historical pathogens of emerging significance

Bartonella species were virtually unrecognized as modern pathogens of humans until the last decade. However, identification of Bartonella species as the agents of cat-scratch disease, bacillary angiomatosis, urban trench fever, and possible novel presentations of Carrion's disease has left little doubt of the emerging medical importance of this genus of organisms. The three primary human pathogenic bartonellae, Bartonella bacilliformis (Carrion's disease), B. henselae (cat-scratch disease), and B. quintana (trench fever), present noteworthy comparisons in the epidemiology, natural history, pathology, and host-microbe interaction that this review will briefly explore.     

Serological Study of Bartonella henselae in Cat Scratch Disease in Japan

It has become clear that Bartonella henselae is a common cause of cat scratch disease (CSD). The indirect fluorescence antibody (IFA) test for detection of IgG and IgM antibodies to B. henselae concerning CSD showed that 5 (50%) of 10 patients with CSD had a serum IgG antibody titer of 1:128 or more and that 2 (20%) patients had a serum IgM antibody titer of 1:20 or more. One of 7 asymptomatic members of patients' families (14%) had IgG antibody to B. henselae at a titer of 1:256. IgM antibody to B. henselae was not detected in sera from the patients' families. Both IgG and IgM antibodies to B. henselae were not detected in sera from the healthy control group. These data suggest that B. henselae may be a cause of CSD in Japan.