Improvement of Bartonella henselae DNA Detection in Cat Blood Samples by Combining Molecular and Culture Methods

Pradofloxacin for Treatment of Bartonella henselae in Experimentally Inoculated Cats

Bartonella henselae is associated with numerous clinical syndromes in people. Cats are the definitive hosts for B. henselae, develop high levels of bacteremia, and are associated with human infections, particularly in the presence of Ctenocephalides felis. Several antibiotic protocols used for the treatment of B. henselae infection in cats have failed to clear bacteremia. The purpose of this study was to assess the safety and efficacy of a high-dose pradofloxacin protocol to eliminate B. henselae bacteremia. Bartonella henselae infection was initiated in 8 cats by intravenous inoculation of infected feline blood and then pradofloxacin was administered at 7.5 mg/kg, PO, twice daily for 28 days, starting 12 weeks after inoculation. Complete blood cell counts were performed prior to pradofloxacin administration and then every 2 weeks for 10 weeks. Bartonella PCR assay was performed prior to pradofloxacin administration and approximately every 2 weeks for 10 weeks and then weekly for 4 weeks. Methylprednisolone acetate (5 mg/kg) was administered by intramuscular injection to all cats on week 10. The cats remained normal and none developed a hematocrit, platelet count, lymphocyte count, or neutrophil count outside of the normal reference ranges. In the one month prior to pradofloxacin administration, all cats were PCR-positive for Bartonella DNA on at least two of four sample dates; after pradofloxacin administration, all cats were negative for B. henselae DNA in blood on all nine sample dates. The protocol appears to be safe and failure to amplify B. henselae DNA from the blood after the administration of pradofloxacin and one dose of methylprednisolone acetate suggests either an antibiotic effect or the organism was cleared spontaneously.

The influence of growth time on the identification of Bartonella henselae strains by MALDI-TOF mass spectrometry

Bartonella spp. are bacteria responsible for neglected diseases worldwide. Bartonella henselae is the species most associated with human infections. It is associated with a large spectrum of clinical manifestations and is potentially fatal. The identification of Bartonella spp. is considered a challenge in clinical routine. These bacteria are fastidious, and the time required to isolate them varies from one to six weeks. MALDI-TOF mass spectrometry has emerged as an application for research on Bartonella spp. , and has still been little explored. We investigated whether three different B. henselae strains with different growth times-14 and 28 days-could be correctly identified by MALDI-TOF mass spectra fingerprint comparison and matching. We found that the spectra from strains with different growth times do not match each other, leading to misidentification. We suggest creating database entries with multiple spectra from strains with different growth times to increase the chances of accurate identification of Bartonella spp. by MALD-TOF MS.

Bartonella henselae as a putative trigger for chronic type 2 leprosy reactions

Leprosy reactions are an acute inflammatory phenomenon that can arise before diagnosis, during treatment, or after cure of leprosy. These reactions are considered one of the main diseases that cause physical disabilities. Immunosuppressive treatment for these immune responses makes these patients susceptible to coinfections, which can trigger new leprosy reactions. The main objective of this study was to evaluate the occurrence of infection by Bartonella sp. in blood samples from 47 patients who had untreatable episodes of type 2 leprosy reactions for more than six months, comparing them with a control group. Cultures and molecular methods (PCR) were used. Amplicons from species-specific reactions and sequencing showed a higher prevalence of Bartonella henselae infection in patients, 19/47 (40.4 %), compared to control, 9/50 (18.0 %), p = 0.0149. Five patients accepted treatment for coinfection, and all showed improvement in leprosy reactions with treatment for B. henselae infection. We conclude that these bacteria can trigger chronic reactions of type 2 leprosy and should be investigated in these patients. SUMMARY LINE: Patients who have chronic type 2 leprosy reactions are more susceptible to Bartonella henselae infection than controls: 19/47 (40.4 %) compared 9/50 (18.0 %), p = 0.0149.

Genome Analysis of ST1 Bartonella henselae, a Zoonotic Pathogen Causing Endocarditis in an Elderly Patient in China

Infective endocarditis (IE) is a rare disease but with high associated mortality. Currently, the mainstays of diagnosis are still echocardiography and blood cultures. Here, we reported a case of infective endocarditis with negative blood cultures, and blood and aortic valve tissue metagenomic next-generation sequencing (mNGS) results suggested Bartonella henselae. In addition, we obtained the whole genomic sequence of B. henselae ZJBH strain. To our knowledge, this is the first report of B. henselae genomic analysis isolated from clinic in China. Furthermore, we described the whole genome sequencing (WGS) data incorporating all B. henselae from diverse sources worldwide and shed light on underlying risk of B. henselae transmitted between cats and humans.

Detection of Bartonella henselae DNA in the blood of patients with livedoid vasculopathy

BACKGROUND

Livedoid vasculopathy (LV) manifests as ulcers and atrophic white scars on the lower extremities. The main known etiopathogenesis is hypercoagulability with thrombus formation, followed by inflammation. Thrombophilia, collagen and myeloproliferative diseases may induce LV, but the idiopathic (primary) form predominates. Bartonella sp. may cause intra-endothelial infection and skin manifestations caused by these bacteria may be diverse, including leukocytoclastic vasculitis and ulcers.

OBJECTIVE

The aim of this study was to investigate the presence of bacteremia by Bartonella spp. in patients with difficult-to-control chronic ulcers diagnosed as primary LV.

METHODS

Questionnaires and molecular tests (conventional PCR, nested PCR and real-time PCR) were applied and liquid and solid cultures were performed in the blood samples and blood clot of 16 LV patients and 32 healthy volunteers.

RESULTS

Bartonella henselae DNA was detected in 25% of LV patients and in 12.5% of control subjects but failed to reach statistically significant differences (p = 0.413).

STUDY LIMITATIONS

Due to the rarity of primary LV, the number of patients studied was small and there was greater exposure of the control group to risk factors for Bartonella spp.

INFECTION

CONCLUSION

Although there was no statistically significant difference between the groups, the DNA of B. henselae was detected in one of every four patients, which reinforces the need to investigate Bartonella spp. in patients with primary LV.

Cat scratch disease: What to do with the cat?

Purpose

Cat scratch disease (CSD) frequently has ophthalmologic manifestations. The ophthalmologist's approach to treating neuroretinitis is familiar, but few eye care providers are comfortable answering the next question of “what do I do with my cat?” Published guidelines are often vague in answering the complexities of real-life conundrums that can lead patients and their doctors to believe that risk mitigation should involve removal of the animal. Here, we present demonstrative scenarios informed by clinical practice and provide updated recommendations.

Observations

A 10-year-old boy presented with reduced vision in the right eye. Funduscopic examination identified optic nerve head edema with subretinal fluid, and a macular star developed one week later, consistent with the diagnosis of neuroretinitis. Serology confirmed Bartonella henselae antibodies and a diagnosis of CSD. The father disclosed that the family has recently adopted three kittens, who have scratched the boy and the patient's younger sister. The physician and patient's family find themselves at a loss regarding best practices for what should be done with the kittens.

Conclusions and Importance

B. henselae has been detected in a variety of mammals and can be transmitted via vectors such as fleas. Even well-appearing animals can transmit the bacteria, months to years after their initial infection. Symptoms, clinical and laboratory findings will depend on bacterial load and strain virulence, as well as the physiological/immunological status of the host, with people at the extremes of age and the immunocompromised being at greater disease risk. Flea control is crucial to minimize transmission risk. Our veterinary expert (EBB) recommends testing (with serology and PCR) and treating infected animals (with doxycycline and a quinolone). Patients should be counseled to speak with their pets’ veterinarian. When addressing the concerns of our CSD patients in clinical practice, ophthalmologists should be aware of the strategies for minimizing Bartonella transmission risk, and cognizant of the One Health approach for managing zoonoses.

Threat under cats' claws: Molecular detection and risk factors for zoonotic Bartonella species in blood and claw samples from cats in Brazil

Bartonelloses are zoonoses widely dispersed throughout the world caused by bacteria of the genus Bartonella. Domestic cats play an important role in the epidemiology of bartonelloses, since these animals are considered natural hosts of B. henselae, B. koehlerae and B. clarridgeiae. This study aimed to determine the occurrence of Bartonella spp. in domestic cats' blood and claw samples in the southern region of Bahia, northeastern Brazil. Additionally, the main clinical and hematological changes in Bartonella-positive animals were investigated, as well as the risk factors associated with the infection. For this purpose, 188 indoor house domestic cats were clinically evaluated and submitted to claw and blood sample collection. Additionally, data regarding the clinical history of the animals were recorded. Out of 188 cats' blood samples, 20.7% (39/188) were positive in the qPCR for Bartonella spp. based on the nuoG gene. Out of 39 claw samples collected, 23.9% (9/39) were positive for Bartonella spp. The parameters of the blood and claw samples ranged from 1.42 to 395,000 and 4.32 - 108,000 copies/μL of a fragment of Bartonella nuoG gene, respectively. The amplified sequences shared identity ranging from 99% to 100% with the three main cat-related Bartonella species. Higher platelet values (p = 0.0082) were observed in animals positive for Bartonella spp. Young and unsterilized cats with outdoor access were more prone to infection by Bartonella spp. The data reported here demonstrated the occurrence of Bartonella spp. in blood and claw samples from cats in northeastern Brazil showing no significant clinical and hematological disorders.

Serological and Molecular Detection of Bartonella henselae in Cats and Humans From Egypt: Current Status and Zoonotic Implications

Bartonellosis is a vector-borne zoonotic disease caused by the intracellular bacterium of genus Bartonella. The disease has a worldwide distribution and cats represent the major reservoir of this disease. Despite its global distribution, very limited previous studies have investigated the occurrence of bartonellosis in cats and their owners in Egypt. In an endeavor to explore this topic, we investigated the occurrence of Bartonella henselae (B. henselae) infection in 225 samples (blood, saliva, and claw) obtained from 75 healthy cats in Upper Egypt. These samples were routinely obtained during veterinary clinic visits. This study also involved an examination of 100 humans, including cat owners and people with a history of contact with cats. Attempted isolation and identification of B. henselae in cats were also performed. Furthermore, PCR was performed for molecular identification of B. henselae in blood samples from cats. Meanwhile, an immunofluorescent assay was performed to study the seroprevalence of B. henselae infection in humans. In this study, B. henselae could not be isolated from any of the examined blood, saliva, or claw samples from cats. Interestingly, B. henselae was identified molecularly in 8% (6/75) of blood samples from cats. The seroprevalence of B. henselae in humans was 46% and its occurrence was higher in females (46.6%) than in males (41.7%) (P = 0.748). B. henselae infection was higher among cat owners [51.4% (19/37)] than among people with a history of contact with cats [42.9% (27/63)] (P = 0.410). Infection was higher in rural regions [79.5% (31/39)] than in urban regions [24.6% (15/61)] (P < 0.001). Collectively, this data provide interesting baseline information about the occurrence of B. henselae in cats and humans in Upper Egypt, which reflects the potential zoonotic transmission of this bacterium. Future study is mandatory to explore the occurrence of B. henselae in major reservoirs in Egypt.

In silico analyses and design of chimeric proteins containing epitopes of Bartonella henselae antigens for the control of cat scratch disease

Bartonella henselae is a Gram-negative bacterium that causes cat scratch disease (CSD), as well as bacteremia, endocarditis, and other clinical presentations. CSD remains one of the most common infections caused by bacteria in the genus Bartonella, and it is transmitted to humans through a scratch or cat bite. Vaccination and more efficient diagnostic methods would represent a promising and sustainable alternative measure for CSD control in humans and animals. Here, we described the in silico analyses and design of three recombinant chimeric proteins (rC1, rC2, and rC3), for use in the control of CSD. The chimeras were constructed with epitopes identified from the sequences of the GroEL, 17 kDa, P26, BadA, Pap31, OMP 89, and OMP 43, previously described as the most important B. henselae antigens. The rC1, rC2, and rC3 were expressed and purified using a heterologous system based on Escherichia coli and reacted with antibodies present in the sera of humans naturally infected. The chimeric proteins were used to immunize mice using Freund adjuvant, and the humoral immune response was evaluated. Animals immunized with rC1 and rC3 showed a significant IgG antibodies response from the 28th day (P < 0.05), and the animals immunized with the rC2 from the 35th day (P < 0.05) remained until the 56th day of experimentation, with a titer of 1:3200 (P < 0.05), 1:1600 (P < 0.05) and 1:1600 (P < 0.05) from rC1, rC2, and rC3, respectively. Significant production of IgA and IgG1 isotype was detected in animals immunized with rC1 and rC2 proteins. Additionally, analysis using 13 serum samples from naturally infected patients showed that the proteins are recognized by antibodies present in sera, reinforcing the possibility of using these chimeras for CSD control. KEY POINTS: • The recombinant chimeras were expressed in Escherichia coli with 37 kDa (rC1), 35 kDa (rC2), and 38 kDa (rC3). • Animals immunized with rC1, rC2, and rC3 showed significant antibody response. • The chimeras were recognized by the sera of naturally infected patients.

Two-year history of lymphadenopathy and fever caused by Bartonella henselae in a child

We report the case of a 6-year-old boy that presented with enlarged lymph nodes on his neck. He complained of tiredness and discouragement, which worsened during feverish periods. There were no relevant laboratory test abnormalities and serological tests were not reactive. Bartonella henselae DNA was detected by species-specific nested polymerase chain reaction. After treatment, the patient progressed with no fever or lymphadenopathy. Bartonellosis is a group of infectious diseases caused by bacteria of the genus Bartonella. This case report is a useful reminder to clinicians that long-term fever of unknown origin can be related to B. henselae infection, even if the specific serology is not reactive.

Genetic diversity and Multilocus Sequence Typing Analysis of Bartonella henselae in domestic cats from Southeastern Brazil

Bartonella henselae is the causative agent for the infectious disease Cat Scratch Disease (CSD), which can be fatal. Domestic and wild felines are known to be its main mammal reservoirs. The present study aimed to investigate the occurrence and genetic diversity of Bartonella spp. in cats sampled in São Paulo (SP) and Minas Gerais (MG) States, Southeastern Brazil. Based on a quantitative real-time PCR (qPCR) assay, a Bartonella sp. nuoG gene fragment was detected in 39.9% (122/306) of the blood samples (46/151 cats of SP; 76/155 cats of MG). The blood samples were submitted to a pre-enrichment culture technique that allowed the detection of 12 additional positive samples, which showed to be negative in the qPCR using DNA blood samples as templates. Furthermore, five B. henselae isolates were obtained from qPCR-negative samples for both blood and pre-enrichment culture. Seven out of 24 Ctenocephalides felis fleas were positive for Bartonella spp. in the qPCR assay; 4/7 positive fleas were collected from Bartonella-negative cats. Twenty-three rpoB B. henselae cloned sequences were obtained from nine cats' blood samples, showing the occurrence of 13 different genotypes. Median-joining network and SplitsTree distance analysis showed that the obtained sequences represented distinct B. henselae genotypes when compared to those previously deposited in GenBank. Intra-host diversity was found, since different rpoB genotypes of B. henselae were detected in individual single cats. Bartonella henselae isolates showed two allelic profiles (ST37 in cats from MG state and ST9 in SP state) by MLST (Multilocus Sequence Typing) based on sequencing of eight molecular markers. The present study is the first molecular report of Bartonella sp. in cats from Minas Gerais State. In summary, this body of work showed the occurrence of different B. henselae rpoB genotypes at an intra-reservoir host level. Based on qPCR from blood samples and pre-enrichment liquid culture and isolation, occurrence of 33.1% (50/151) and 56.8% (88/155) for Bartonella sp. was found in cats from SP and MG states, respectively. Two different allelic profiles of B. henselae were found in cats from the states of São Paulo (ST9) and Minas Gerais (ST37), suggesting a clonal evolution of Bartonellae in a certain geographical region.

Bartonella henselae Antibodies in Serum and Oral Fluid Specimens from Cats

Cats are the primary reservoir host for Bartonella henselae(B. henselae), an etiological agent of human bartonellosis, including cat scratch disease. Although Bartonella DNA has been amplified from salivary swabs from cats, dogs and humans, we are not aware of studies investigating Bartonella antibodies in oral fluid (OF). Using inhouse and commercial immunofluorescence antibody assays (IFA), the objective of this study was to detect and compare antibodies against B. henselae in paired OF and serum specimens from cats. Specimens were collected from shelter and client-owned cats. For serum specimens, B. henselae seroreactivity was 78% for both the inhouse and commercial IFA assays and 56.8% for OF specimens. Comparing serum and OF specimens, there was moderate Kappa agreement (Cohen's k = 0.434) for detection of B. henselae antibodies. Oral fluid antibodies were more likely measurable in cats with high B. henselae serum antibody titers when compared with low antibody titers. In conclusion, B. henselae OF IFA antibody measurements were less sensitive compared to serum IFA measurements of ≥1:64. Oral fluid antibodies were detected more often in cats with high B. henselae serum antibody titers. Therefore, OF antibodies, detectable by IFA, is of limited utility for epidemiological or diagnostic testing in cats.

Analytical and clinical evaluation of new automated chemiluminescent immunoassays for the detection of IgG and IgM anti-Bartonella henselae antibodies

Serological diagnosis of Bartonella henselae infection mainly rely on microscopic immunofluorescence assays (IFA), which are however time-consuming and poorly standardized. The aim of the study was to assess the use of the new fully automated VirClia® chemiluminescent immunoassays for the detection of IgG and IgM anti-B. henselae antibodies. Eighty-one patients with a well-defined B. henselae infection as well as 80 patients with an alternative disease were included. The VirClia® IgG antibody assay showed a sensitivity of 79.0% and a specificity of 93.8% for the diagnosis of B. henselae infection. For the VirClia® IgM assay, results were more conflicting with a sensitivity of 42.0% and a specificity of 98.2% to predict IFA IgM results. In 11 additional patients with uninterpretable IFA due to autoimmune antibodies, VirClia® assays were able to deliver valuable quantitative results. The VirClia® IgG assay shows good analytical and clinical performances and could be easily integrated in the diagnostic workflow of B. henselae infection.

Prevalence of Bartonella spp. Infection in Patients with Sickle Cell Disease

Background: The inherent characteristics of the sickle cell disease (SCD), the most common genetic hematological disorder, increase the propensity of infections. Bartonella spp. are emerging and neglected bacteria. A large spectrum of clinical manifestations has been linked to bartonella bloodstream infection in the last two decades that can cause fatal outcomes, especially in immunodeficient patients. The goal of this study was to evaluate the prevalence of bartonella infection in SCD patients. Materials and Methods: We evaluated Bartonella spp. prevalence in 107 SCD patients. Blood samples and enrichment blood cultures were analyzed by molecular detection of Bartonella spp. DNA. Bartonella DNA was amplified using conventional genus-specific Bartonella PCR which amplifies the Intergenic Transcribed Spacer region and Bartonella henselae-specific nested PCR which amplifies the FtsZ gene. Positive patient DNAs were tested with ssrA conventional PCR. All amplicons were sequenced. Findings: Ten of 107 patients tested positive for B. henselae infection in at least one molecular test. All obtained amplicons were sequenced and similar to B. henselae sequences deposited in GenBank (accession number BX897699). Based on statistical results, bloodstream infection with B. henselae was not associated with animal contact or blood transfusions. Conclusion: We detected B. henselae DNA in 10 (9.3%) SCD studied patients. These patients were notified and treatment was offered to them.

Aortic valve endocarditis due to Bartonella clarridgeiae in a dog in Brazil

We report the first documented case of endocarditis associated with Bartonella clarridgeiae in a dog in Latin America. Infective vegetative valvular aortic endocarditis was diagnosed in a 10-year-old male mixed breed dog. The dog presented grade V/VI systolic and diastolic murmur, hyperthermia, and progressive weight loss. Cardiomegaly and presence of diffuse alveolar pattern in the lung fields were observed in the thorax radiography evaluation. Irregular and hyperechogenic structures adhered to the aortic leaflets, causing obstruction of the left ventricular outflow tract and severe aortic insufficiency, were observed in the echocardiography evaluation. A vegetative, whitish, hardened structure measuring 1.0 cm in diameter was observed in aortic semilunar valve at necropsy. Based on a combination of pre-enrichment insect-based medium liquid culture, quantitative real-time and conventional PCR assays based on nuoG and gltA genes, respectively, followed by sequencing and phylogenetic inferences, B. clarridgeiae DNA was detected in the patient's aortic valve lesions. Clinical, echocardiographic, anatomopathologic and molecular features supported the diagnosis of severe aortic vegetative endocarditis possibly caused by B. clarridgeiae in a dog in Brazil.

Bartonella henselae bacteremia diagnosed post-mortem in a myelodysplastic syndrome patient

This study involves a 49-year-old male, who for three years suffered with a myelodysplastic syndrome and who needed frequent blood transfusions. One day following a transfusion, he presented fever and abdominal pain. The fever became persistent and only improved temporarily with two cycles of intravenous ciprofloxacin. Nearly 120 days after beginning the second cycle of treatment, he had experienced a weight loss of 16 kg and recurring fever. Screening for fever of unknown origin was conducted, including Bartonella infection. No etiology could be found. The patient improved with an antimicrobial regimen composed of oral doxycycline and intravenous ciprofloxacin. After 15 days afebrile, the patient was discharged with a four-month oral prescription of doxycycline and ciprofloxacin. Eight months following the antibiotic treatment, the patient received an allogeneic bone marrow transplant. Five days following the transplant, the patient initiated a febrile neutropenia and died. From a blood sample collected and stored at the time of hospitalization, a microbiological and molecular study was performed again. Blood- and liquid culture-PCRs from the same blood sample were all negative, but an isolate from solid subculture was found. The molecular reactions from this isolate were all positive and the sequence was 100% homologous to Bartonella henselae . The present report points to the limitations of laboratory techniques currently available for investigation of possible cases of bartonellosis in clinical practice, and the potential risk of Bartonella spp. transmission through blood transfusions.

Cutaneous manifestations of bartonellosis

Bartonellosis are diseases caused by any kind of Bartonella species. The infection manifests as asymptomatic bacteremia to potentially fatal disorders. Many species are pathogenic to humans, but three are responsible for most clinical symptoms: Bartonella bacilliformis, Bartonella quintana, and Bartonella henselae. Peruvian wart, caused by B. bacilliformis, may be indistinguishable from bacillary angiomatosis caused by the other two species. Other cutaneous manifestations include maculo-papular rash in trench fever, papules or nodules in cat scratch disease, and vasculitis (often associated with endocarditis). In addition, febrile morbilliform rash, purpura, urticaria, erythema nodosum, erythema multiforme, erythema marginatus, granuloma annularis, leukocytoclastic vasculitis, granulomatous reactions, and angioproliferative reactions may occur. Considering the broad spectrum of infection and the potential complications associated with Bartonella spp., the infection should be considered by physicians more frequently among the differential diagnoses of idiopathic conditions. Health professionals and researchers often neglected this diseases.

Feline Vector-Borne Diseases in North America

"In North America, with the exceptions of Bartonella henselae and Cytauxzoon felis, feline vector-borne diseases (FVBDs) have been minimally studied in domestic cats. Cats can be infected with many of the same vector-borne pathogens that infect dogs. Nonspecific clinical signs linked to FVBDs and low prevalence of certain vector-borne pathogens contribute to a limited awareness of FVBDs in sick cats. As clinicians become informed about FVBDs and as vector-borne disease diagnostics are routinely applied to evaluate sick cats, we will gain a stronger understanding of vector-borne pathogens in cats. This article focuses on recent findings related to FVBDs."

False Negative Results in Bartonellosis Diagnosis

We report a fatal case of Bartonella henselae bacteremic patient. He had negative serology and PCRs from whole blood and liquid culture; only ftsZ nested PCR was positive from the blood liquid culture. The isolate had positive PCRs. When considered, bartonellosis diagnosis can be still challenging because of technical limitations.

Pathogens in fleas collected from cats and dogs: distribution and prevalence in the UK

Background

Fleas (Siphonaptera) are the most clinically important ectoparasites of dogs and cats worldwide. Rising levels of pet ownership, climate change and globalisation are increasing the importance of a detailed understanding of the endemicity and prevalence of flea-borne pathogens. This requires continued surveillance to detect change. This study reports a large-scale survey of pathogens in fleas collected from client-owned cats and dogs in the UK.

Methods

Recruited veterinary practices were asked to follow a standardised flea inspection protocol on a randomised selection of cats and dogs brought into the practice in April and June 2018. A total of 326 practices participated and 812 cats and 662 dogs were examined. Fleas were collected, identified to species and pooled flea samples from each host were analysed for the presence of pathogens using PCR and sequence analysis.

Results

Overall, 28.1% of cats and 14.4% of dogs were flea infested. More than 90% of the fleas on both cats and dogs were cat fleas, Ctenocephalides felis felis. Fleas of the same species from each infested host were pooled. DNA was amplified from 470 of the pooled flea samples using conventional PCR, 66 of which (14% ± 95% CI 3.14%) were positive for at least one pathogen. Fifty-three (11.3% ± 95% CI 2.85%) of the pooled flea DNA samples were positive for Bartonella spp., 35 were from cats and 4 from dogs, the remainder had no host record. Seventeen of the Bartonella spp. samples were found to be Bartonella henselae, 27 were Bartonella clarridgeiae (of two different strains), 4 samples were Bartonella alsatica and one was Bartonella grahamii; 4 samples could not be identified. Fourteen (3% ± 95% CI 1.53%) of the flea DNA samples were found to be positive for Dipylidium caninum, 10 of the D. caninum-infected samples were collected from cats and one from a dog, the other 3 positive flea samples had no host species record. Only 3 flea samples were positive for Mycoplasma haemofelis or Mycoplasma haemocanis; 2 were collected from cats and one had no host species record. Three fleas were positive for both D. caninum and Bartonella spp. One flea was positive for both Bartonella spp. and M. haemofelis or M. haemocanis.

Conclusions

This study highlights the need for ongoing flea control, particularly given the relatively high prevalence of Bartonella spp., which is of concern for both animal welfare and human health. The study demonstrates the ongoing need to educate pet owners about the effects of both flea infestation and also the pathogen risks these fleas present.

Bartonella infections in cats and dogs including zoonotic aspects

Bartonellosis is a vector-borne zoonotic disease with worldwide distribution that can infect humans and a large number of mammals including small companion animals (cats and dogs). In recent years, an increasing number of studies from around the world have reported Bartonella infections, although publications have predominantly focused on the North American perspective. Currently, clinico-pathological data from Europe are more limited, suggesting that bartonellosis may be an infrequent or underdiagnosed infectious disease in cats and dogs. Research is needed to confirm or exclude Bartonella infection as a cause of a spectrum of feline and canine diseases. Bartonella spp. can cause acute or chronic infections in cats, dogs and humans. On a comparative medical basis, different clinical manifestations, such as periods of intermittent fever, granulomatous inflammation involving the heart, liver, lymph nodes and other tissues, endocarditis, bacillary angiomatosis, peliosis hepatis, uveitis and vasoproliferative tumors have been reported in cats, dogs and humans. The purpose of this review is to provide an update and European perspective on Bartonella infections in cats and dogs, including clinical, diagnostic, epidemiological, pathological, treatment and zoonotic aspects.