A case of mistaken identity: a systematic review, meta-analysis, and reinvestigation of hemotropic Mycoplasma spp. infection in Ctenocephalides felis (cat flea).

BACKGROUND: Feline-associated hemotropic Mycoplasma (hemoplasmas) are believed to be transmitted by two primary mechanisms: (1) direct transmission via fighting and (2) vector-borne transmission by the cat flea (Ctenocephalides felis). While the efficiency of transmission by C. felis appears low, most manuscripts focus on the prevalence of hemoplasmas in wild-caught fleas and report either a very low (< 3%) or a high (> 26%) prevalence. Therefore, we aimed to assess the influence of sample processing and PCR methods on C. felis hemoplasma infection prevalence. METHODS: A systemic review of PubMed articles identified 13 manuscripts (1,531 fleas/flea pools) that met the inclusion criteria (performed PCR for >1 hemoplasma on C. felis collected from cats). Risk of bias was assessed utilizing the ROBINS-E tool. Meta-analysis performed in R of these manuscripts found that not washing samples and a common set of 16S rRNA primers first published in Jensen et al. 2001 were associated with increased hemoplasma prevalence. To evaluate the influence of washing on newly collected fleas, we assessed the hemoplasma status of 20 pools of 5 C. felis each, half of which were washed and half not washed. RESULTS: Flea washing did not influence the detection of hemoplasma but instead amplified Spiroplasma. To assess non-specific amplification with the Jensen et al. 2001 primers, 67 C. felis samples (34% previously reported hemoplasma infected) were subject to PCR and sequencing. By this method, hemoplasma was detected in only 3% of samples. In the remaining "hemoplasma infected" fleas, PCR amplified Spiroplasma or other bacteria. CONCLUSIONS: Therefore, we concluded that hemoplasma infection in C. felis is rare, and future flea prevalence studies should sequence all positive amplicons to validate PCR specificity. Further investigation of alternative methods of feline-associated hemoplasma transmission and the ability of C. felis to maintain hemoplasma infection is necessary.

Detection of Anaplasma phagocytophilum in an inflammatory pericardial effusion of a dog.

An 11-year-old female spayed German Wirehaired Pointer with a 1-week history of lethargy, hyporexia, diarrhea, and coughing presented with pericardial effusion causing cardiac tamponade. An echocardiogram revealed no structural cause for pericardial effusion. The pericardial effusion was an exudate with mixed macrophagic and neutrophilic inflammation. Morulae occasionally were found within neutrophils. The pericardial fluid and blood were qPCR and cPCR positive for Anaplasma phagocytophilum (NC State University, Vector-borne Disease Diagnostic Laboratory, Raleigh, NC). The dog's blood was negative by ELISA (Vetscan Flex4 Rapid Test, Zoetis, Parsippany, NJ) for A. phagocytophilum antibodies at initial presentation and subsequently positive (SNAP4DxPlus, IDEXX, Westbrook, ME) 7 days later. After pericardiocentesis and administration of doxycycline (5 mg/kg PO q12h for 14 days), a repeat echocardiogram performed 1 month later showed no recurrence of pericardial effusion.

Treatment of Francisella philomiragia bacteremia in a dog.

To describe the diagnosis and successful treatment of systemic francisellosis in a dog. An 11-year-old female spayed Labrador retriever presented for progressive lethargy, hyporexia, and cough. The dog was febrile with a neutrophilia, nonregenerative anemia, thrombocytopenia, and had increased activity in serum of liver-derived enzymes. Francisella philomiragia was isolated from aerobic blood culture. The dog was treated for 6 weeks with enrofloxacin orally. Repeated aerobic blood cultures after 2 and 6 weeks of antibiotic therapy were negative. The dog was clinically normal 7 months after diagnosis with no evidence of relapse.

Antibodies to Borrelia burgdorferi and Bartonella species in serum and synovial fluid from people with rheumatic diseases.

Vector-borne infections may underlie some rheumatic diseases, particularly in people with joint effusions. This study aimed to compare serum and synovial fluid antibodies to B. burgdorferi and Bartonella spp. in patients with rheumatic diseases. This observational, cross-sectional study examined paired synovial fluid and serum specimens collected from 110 patients with joint effusion between October 2017 and January 2022. Testing for antibodies to B. burgdorferi (using CDC criteria) and Bartonella spp. via two indirect fluorescent antibody (IFA) assays was performed as part of routine patient care at the Institute for Specialized Medicine (San Diego, CA, USA). There were 30 participants (27%) with positive two-tier B. burgdorferi serology and 26 participants (24%) with IFA seroreactivity (≥1:256) to B. henselae and/or B. quintana. Both B. burgdorferi IgM and IgG were detected more frequently in synovial fluid than serum: 27% of patients were either IgM or IgG positive in synovial fluid, compared to 15.5% in serum (P = 0.048). Conversely, B. henselae and B. quintana antibodies were detected more frequently in serum than synovial fluid; overall only 2% of patients had positive IFA titers in synovial fluid, compared to 24% who had positive IFA titers in serum (P < 0.001). There were no significant associations between B. burgdorferi or Bartonella spp. seroreactivity with any of the clinical rheumatological diagnoses. This study provides preliminary support for the importance of synovial fluid antibody testing for documenting exposure to B. burgdorferi but not for documenting exposure to Bartonella spp. IMPORTANCE: This study focuses on diagnostic testing for two common vector-borne diseases in an affected patient population. In it, we provide data showing that antibodies to B. burgdorferi, but not Bartonella spp., are more commonly found in synovial fluid than serum of patients with joint effusion. Since Lyme arthritis is a common-and sometimes difficult to diagnose-rheumatic disease, improving diagnostic capabilities is of utmost importance. While our findings are certainly not definitive for changes to practice, they do suggest that synovial fluid could be a useful sample for the clinical diagnosis of Lyme disease, and future prospective studies evaluating this claim are warranted.

Evaluation of SARS-CoV-2 identification methods through surveillance of companion animals in SARS-CoV-2-positive homes in North Carolina, March to December 2020.

We collected oral and/or rectal swabs and serum from dogs and cats living in homes with SARS-CoV-2-PCR-positive persons for SARS-CoV-2 PCR and serology testing. Pre-COVID-19 serum samples from dogs and cats were used as negative controls, and samples were tested in duplicate at different timepoints. Raw ELISA results scrutinized relative to known negative samples suggested that cut-offs for IgG seropositivity may require adjustment relative to previously proposed values, while proposed cut-offs for IgM require more extensive validation. A small number of pet dogs (2/43, 4.7%) and one cat (1/21, 4.8%) were positive for SARS-CoV-2 RNA, and 28.6 and 37.5% of cats and dogs were positive for anti-SARS-CoV-2 IgG, respectively.

Blood Supplementation Enhances Bartonella henselae Growth and Molecular Detection of Bacterial DNA in Liquid Culture.

Bacteria of the genus Bartonella, a member of the Alphaproteobacteria, are fastidious, Gram-negative, aerobic bacilli that comprise numerous species, subspecies, and genotypes. Bartonella henselae, with a worldwide distribution, infects cats, dogs, horses, humans, and other mammals. Diagnostically, direct detection of Bartonella henselae in patient blood specimens by culture or molecular methods is required to confirm infection with this bacterium. Enrichment blood culture combined with quantitative PCR (qPCR) or ddPCR enhances the sensitivity of direct detection. The addition of sheep blood to liquid culture media increased the Bartonella henselae DNA concentration compared to controls, additionally improving PCR direct detection sensitivity. IMPORTANCE This study aims to improve diagnostic detection of Bartonella henselae. Patient samples are combined with enriched bacterial cultures aimed at growing Bartonella henselae for the best possible chance at detection. However, current Bartonella growth methods could be improved. The DNA extraction method used by most laboratories should also be optimized. Sheep blood was added to increase the growth of Bartonella henselae and multiple DNA extraction methods were to be compared to each other.

The association of host and vector characteristics with Ctenocephalides felis pathogen and endosymbiont infection.

Surveillance of the fleas and flea-borne pathogens infecting cats is important for both human and animal health. Multiple zoonotic Bartonella and Rickettsia species are known to infect the most common flea infesting cats and dogs worldwide: Ctenocephalides felis, the cat flea. The ability of other flea species to transmit pathogens is relatively unexplored. We aimed to determine cat host and flea factors independently associated with flea Bartonella and Rickettsia infection. We also assessed flea and cat infection by flea-host pair and location. To accomplish these aims, we performed qPCR for the detection of Bartonella, hemotropic Mycoplasma, Rickettsia, and Wolbachia DNA using paired cat and flea samples obtained from free-roaming cats presenting for spay or neuter across four locations in the United States. A logistic regression model was employed to identify the effect of cat (sex, body weight, geographic location, and Bartonella, hemotropic Mycoplasma, and Rickettsia spp., infection) and flea (clade and Rickettsia and Wolbachia infection) factors on C. felis Bartonella clarridgeiae infection. From 189 free roaming cats, we collected 84 fleas: Ctenocephalides felis (78/84), Cediopsylla simplex (4/84), Orchopeas howardi (1/84), and Nosopsyllus fasciatus (1/84). Ctenocephalides felis were phylogenetically assigned to Clades 1, 4, and 6 by cox1 gene amplification. Rickettsia asembonensis (52/84) and B. clarridgeiae (16/84) were the most common pathogenic bacteria detected in fleas. Our model identified host cat sex and weight as independently associated with B. clarridgeiae infection in fleas. Rickettsia asembonensis (52/84), Rickettsia felis (7/84) and Bartonella henselae (7/84) were detected in specific clades: R. felis was detected only in Clades 1 and 6 while B. henselae and R. asembonensis were detected only in Clade 4. Wolbachia spp., also displayed clade specificity with strains other than Wolbachia wCfeT only infecting fleas from Clade 6. There was poor flea and host agreement for Bartonella spp., infection; however, there was agreement in the Bartonella species detected in cats and fleas by geographic location. These findings reinforce the importance of considering reservoir host attributes and vector phylogenetic diversity in epidemiological studies of flea-borne pathogens. Widespread sampling is necessary to identify the factors driving flea-borne pathogen presence and transmission.

Feeding on a Bartonella henselae Infected Host Triggers Temporary Changes in the Ctenocephalides felis Microbiome.

The effect of Bartonella henselae on the microbiome of its vector, Ctenocephalides felis (the cat flea) is largely unknown, as the majority of C. felis microbiome studies have utilized wild-caught pooled fleas. We surveyed the microbiome of laboratory-origin C. felis fed on B. henselae-infected cats for 24 h or 9 days to identify changes to microbiome diversity and microbe prevalence compared to unfed fleas, and fleas fed on uninfected cats. Utilizing Next Generation Sequencing (NGS) on the Illumina platform, we documented an increase in microbial diversity in C. felis fed on Bartonella-infected cats for 24 h. These changes returned to baseline (unfed fleas or fleas fed on uninfected cats) after 9 days on the host. Increased diversity in the C. felis microbiome when fed on B. henselae-infected cats may be related to the mammalian, flea, or endosymbiont response. Poor B. henselae acquisition was documented with only one of four infected flea pools having B. henselae detected by NGS. We hypothesize this is due to the use of adult fleas, flea genetic variation, or lack of co-feeding with B. henselae-infected fleas. Future studies are necessary to fully characterize the effect of endosymbionts and C. felis diversity on B. henselae acquisition.

Identification of microbial taxa present in Ctenocephalides felis (cat flea) reveals widespread co-infection and associations with vector phylogeny.

BACKGROUND: Ctenocephalides felis, the cat flea, is the most common ectoparasite of cats and dogs worldwide. As a cause of flea allergy dermatitis and a vector for two genera of zoonotic pathogens (Bartonella and Rickettsia spp.), the effect of the C. felis microbiome on pathogen transmission and vector survival is of substantial medical importance to both human and veterinary medicine. The aim of this study was to assay the pathogenic and commensal eubacterial microbial communities of individual C. felis from multiple geographic locations and analyze these findings by location, qPCR pathogen prevalence, and flea genetic diversity. METHODS: 16S Next Generation Sequencing (NGS) was utilized to sequence the microbiome of fleas collected from free-roaming cats, and the cox1 gene was used for flea phylogenetic analysis. NGS data were analyzed for 168 individual fleas from seven locations within the US and UK. Given inconsistency in the genera historically reported to constitute the C. felis microbiome, we utilized the decontam prevalence method followed by literature review to separate contaminants from true microbiome members. RESULTS: NGS identified a single dominant and cosmopolitan amplicon sequence variant (ASV) from Rickettsia and Wolbachia while identifying one dominant Bartonella clarridgeiae and one dominant Bartonella henselae/Bartonella koehlerae ASV. Multiple less common ASVs from these genera were detected within restricted geographical ranges. Co-detection of two or more genera (Bartonella, Rickettsia, and/or Wolbachia) or multiple ASVs from a single genus in a single flea was common. Achromobacter, Peptoniphilus, and Rhodococcus were identified as additional candidate members of the C. felis microbiome on the basis of decontam analysis and literature review. Ctenocephalides felis phylogenetic diversity as assessed by the cox1 gene fell within currently characterized clades while identifying seven novel haplotypes. NGS sensitivity and specificity for Bartonella and Rickettsia spp. DNA detection were compared to targeted qPCR. CONCLUSIONS: Our findings confirm the widespread coinfection of fleas with multiple bacterial genera and strains, proposing three additional microbiome members. The presence of minor Bartonella, Rickettsia, and Wolbachia ASVs was found to vary by location and flea haplotype. These findings have important implications for flea-borne pathogen transmission and control.

Bartonellosis in Dogs and Cats, an Update.

The unique virulence factors of Bartonella spp make them stealth pathogens that evade the immune system and cause persistent infections that are often difficult to diagnose and treat. Understanding these pathogenic mechanisms allows clinicians to recognize when to pursue diagnostics, how to optimize diagnostic testing and treatment, and ultimately can lead to improved outcomes.

Bartonella henselae Recombinant Pap31 for the Diagnosis of Canine and Human Bartonelloses.

Bartonella spp. comprise a genus of Gram-negative alphaproteobacteria that are slow growing, fastidious, and facultative intracellular pathogens with zoonotic potential. Immunofluorescent antibody assays (IFAs), Western blot (WB), and enzyme-linked immunosorbent assays (ELISAs), the frequently used modalities for the serological diagnosis of canine and human Bartonelloses, generate numerous false negative results. Therefore, the development of a reliable serodiagnostic assay for Bartonelloses is of clinical and epidemiological importance. Pap31, a heme binding surface protein of B. henselae, is associated with bacterial adhesion and related to bacterial colonization. To our knowledge, B. henselae Pap31 and its fragments (N-terminal (NTD), middle (MD), and C-terminal (CTD) domains) have not been investigated for the serodiagnosis of canine and human Bartonelloses. In this study, we evaluate the diagnostic utility of B. henselae recombinant whole Pap31 (rPap31) and Pap31 fragments by ELISA using sera from 70 dogs (36 Bartonella spp. IFA-positive (naturally infected), and 34 Bartonella spp. IFA- and PCR-negative (control dogs)) and 36 humans (18 Bartonella spp. IFA-positive (naturally infected) and 18 controls)). In the dogs, the area under the curve (AUC) score of recombinant whole Pap31 was 0.714 with a sensitivity of 42% and specificity of 94% at an OD cutoff value of 0.8955. Among the evaluated recombinant Pap31 proteins for the diagnosis of canine Bartonelloses, rPap31-NTD yielded the highest AUC score of 0.792 (95% CI 0.688-0.895) with a sensitivity of 44% and specificity of 100% at a cutoff value of 1.198. In concordance with this finding, rPap31-NTD also had the highest AUC score of 0.747 (95% CI 0.581-0.913) among the Pap31 recombinant proteins for the diagnosis of human Bartonelloses, with 39% sensitivity and 94% specificity at a cutoff value of 1.366. Recombinant whole Pap31 (rPap31) resulted in 72% sensitivity and 61% specificity at a cutoff value of 0.215 for human Bartonelloses. Due to either low sensitivity or questionable specificity, our findings indicate that recombinant Pap31 and the selected fragments may not be appropriate diagnostic targets in detecting anti-Bartonella antibodies in Bartonella-infected dogs and humans. The findings from this study can be used to further assess the antigenicity and immunogenicity of B. henselae Pap31 as a diagnostic target.

Outcomes of esophageal and gastric bone foreign bodies in dogs.

BACKGROUND: Bone foreign bodies are commonly encountered in small animal practice. Esophageal bone foreign bodies (E-bFBs) warrant removal, whereas gastric bone foreign bodies might not. OBJECTIVES: Describe management and outcomes for dogs with esophageal or gastric bone foreign bodies. ANIMALS: One hundred twenty-nine dogs with esophageal (n = 45) or gastric (n = 84) bone foreign bodies. METHODS: Retrospective review of medical records. RESULTS: Dogs with E-bFBs were younger than dogs with gastric bone foreign bodies (median age esophageal, 4 years [IQR 2-8]; median age gastric, 6 years [IQR 3-10]; P = .03), and had a higher bone cross-sectional area relative to body weight (median esophageal, 98.21 mm2 /kg [IQR 48.25-142.6]; median gastric, 28.6 mm2 /kg [IQR 17.25-64.28]; P < .001). Forty-two of 45 esophageal foreign bodies were resolved non-surgically and 3 by esophagotomy. Esophageal erosions were more likely with distal entrapment (OR 12.88, [95% CI 31.95-129.29], P = .01) and longer duration (OR 18.82 [95% CI 2.22-273.97], P = .01). Sixty-two of 84 bone gastric foreign bodies were left in situ. Endoscopic removal was successful in 20 of 22 (91%; 95% CI 70-99) attempts. CONCLUSIONS AND CLINICAL IMPORTANCE: While all E-bFBs were dislodged either by advancement into the stomach, endoscopic removal, or esophagotomy, the majority of gastric bone foreign bodies were left in situ for dissolution, with no reported complications. Gastric advancement of E-bFBs should be considered when oral removal is not feasible, and dissolution can be considered even with large bones.

Bartonella spp. seroepidemiology and associations with clinicopathologic findings in dogs in the United States.

BACKGROUND: Improved understanding of Bartonella spp. serology in dogs may aid clinical decision making. OBJECTIVE: Describe demographic and geographic patterns of Bartonella spp. seroreactivity in dogs, and describe hematologic and serum biochemical abnormalities in Bartonella spp. seroreactive and nonseroreactive dogs. ANIMALS: Serum samples from 5957 dogs in the United States, previously submitted to IDEXX Reference Laboratories. METHODS: Serum was tested using 3 indirect ELISAs for B. henselae, B. vinsonii subsp. berkhoffii, and B. koehlerae. Complete blood count and serum biochemistry panel results were reviewed retrospectively. RESULTS: Overall, 6.1% of dogs were Bartonella spp. seroreactive. Toy breeds were less likely to be seroreactive (3.9%) than mixed breeds (7.5%; adjusted odds ratio [aOR], 0.48; 95% confidence interval [CI], 0.32-0.72), and dogs <1 year old were less likely to be seroreactive (3.4%) than dogs 1 to 5.5 years of age (7.3%; aOR, 0.42; 95% CI, 0.23-0.72). Dogs in the West South Central (9.8%) and South Atlantic (8.8%) regions were more likely than dogs elsewhere in the United States to be seroreactive (aOR, 2.22; 95% CI, 1.31-3.87; aOR, 2.44; 95% CI, 1.38-4.36). CONCLUSIONS AND CLINICAL IMPORTANCE: Demographic and geographic findings for Bartonella spp. exposure were broadly comparable to previously reported patterns.

Prevalence of Vector-Borne Pathogens in Reproductive and Non-Reproductive Tissue Samples from Free-Roaming Domestic Cats in the South Atlantic USA.

Reservoir to multiple species of zoonotic pathogens, free-roaming cats (FRCs) interact with domestic and wild animals, vectors, and humans. To assess the potential for feline vector-borne pathogens to be vertically transmitted, this study surveyed ear tip and reproductive tissues of FRCs from two locations in the South Atlantic United States for Anaplasma, Bartonella, Ehrlichia, hemotropic Mycoplasma, and Rickettsia species. We collected ovary (n = 72), uterus (n = 54), testicle (n = 74), and ear tip (n = 73) tissue from 73 cats, and fetal (n = 20) and placental (n = 19) tissue from 11 queens. Pathogen DNA was amplified utilizing qPCR, confirmed by sequencing. Cats were more frequently Bartonella henselae positive on reproductive tissues (19%, 14/73) than ear tip (5%, 4/73; p = 0.02). B. henselae was amplified from fetus (20%, 4/20) and placenta samples (11%, 2/19). Bartonella spp. infection was more common in cats from North Carolina (76%, 26/34) than Virginia (13%, 5/39; p < 0.0001). Fourteen percent (10/73) of both ear tip and reproductive tissues were positive for hemotropic Mycoplasma spp. Anaplasma, Ehrlichia, and Rickettsia spp. DNA was not amplified from any cat/tissue. These findings suggest that B. henselae preferentially infected cats' reproductive tissue and reinforces the importance of investigating the potential for B. henselae vertical transmission or induction of reproductive failure.

Comparison of Serological and Molecular Assays for Bartonella Species in Dogs with Hemangiosarcoma.

Currently, a gold standard diagnostic test for Bartonella infection in dogs is lacking. This represents a critical limitation for the development and evaluation of new diagnostic tests, as well as for the diagnosis of, and research on, bartonellosis in dogs. This retrospective observational study aims to compare the results of commonly performed and newly-reported Bartonella spp. diagnostic tests in banked clinical specimens from 90 dogs with hemangiosarcoma (HSA) using composite reference standard (CRS) and random effects latent class analysis (RE-LCA) techniques. Samples from each dog were tested using six serological or molecular diagnostic assays, including indirect fluorescent antibody (IFA) and Western blot (WB) for the detection of antibodies in serum, and qPCR and droplet digital PCR (ddPCR) in blood and fresh frozen tissue biopsy samples (mainly splenic HSA tumors and histopathologically normal spleen or skin/adipose tissue). Bartonella infection prevalence was estimated to be 78% based on the CRS (parallel testing with all six assays), and 64% based on the RE-LCA model. The assay with the highest diagnostic accuracy was qPCR performed on fresh frozen tissue biopsy samples (sensitivity: 94% by RE-LCA and 80% by CRS; specificity: 100%). When comparing newly-reported to traditional Bartonella diagnostic assays, ddPCR was more sensitive for the detection of Bartonella DNA than qPCR when testing blood samples (36% vs. 0%, p < 0.0001). Dogs that were positive on serological assays alone with negative molecular assays were highly unlikely (<3%) to be classified as infected by the RE-LCA model. These data indicate that Bartonella spp. DNA can be PCR amplified from fresh frozen tissues from a majority of dogs with HSA using both qPCR and ddPCR, supporting the use of these methods for future controlled studies comparing the prevalence of Bartonella spp. DNA in the tissue of dogs with HSA to that of unaffected controls.

Schizophrenia and Bartonella spp. Infection: A Pilot Case-Control Study.

Recently, infections with emerging zoonotic bacteria of the genus Bartonella have been reported in association with a range of central nervous system (CNS) symptoms. Currently, it remains unknown if Bartonella spp. infection is associated with symptoms of schizophrenia/schizoaffective disorder (SCZ/SAD). The objective of this study was to determine if there is an association between Bartonella species infection and SCZ/SAD. A secondary objective was to determine if SCZ/SAD symptoms were more severe among participants with documented Bartonella spp. infection. Using a case-control study design, 17 cases and 13 controls were evaluated with a series of clinical and cognitive assessments. Blood samples were collected and tested for Bartonella spp. infection using serological, microbiological, and molecular techniques. People with SCZ/SAD were more likely than healthy volunteers to have Bartonella spp. DNA in their bloodstream, with 11 of 17 cases (65%) positive by Bartonella spp. droplet digital PCR (ddPCR). In comparison, only one healthy volunteer was Bartonella spp. ddPCR positive (8%, p = 0.0024). Based on serology, Bartonella spp. exposure was common among people with SCZ/SAD (12 of 17) as well as among healthy volunteers (12 of 13), with no significant difference between the groups (p = 0.196). Within the case group of people with SCZ/SAD, there was no significant difference in SCZ/SAD severity scores between people with and without ddPCR evidence of Bartonella spp. infection. This pilot study provides preliminary evidence in support of future investigations that should examine a potential contribution of Bartonella spp. infection to SCZ/SAD.

Demographics and travel history of imported and autochthonous cases of leishmaniosis in dogs in the United States and Canada, 2006 to 2019.

BACKGROUND: Leishmania infantum infections are reported in foxhounds throughout the United States (US) and Canada, but only rarely in other dog breeds. A seroprevalence report from 2006 documented leishmaniosis in foxhounds (8.9%) tested in the US between 2000 and 2003. All other breeds were seronegative. OBJECTIVE: To reexamine demographics and travel history of L. infantum-infected dogs in the US and Canada, we hypothesize detection of L. infantum in more foxhounds than nonfoxhounds and that infected nonfoxhounds will have traveled to endemic regions. ANIMALS: A total of 125 dogs positive for L. infantum by immunofluorescent antibody, PCR, or both. METHODS: Retrospective, descriptive study of L. infantum-infected dogs between 4 January 2006 and 22 May 2019. Travel history and known lineage to foxhounds was collected from questionnaires. RESULTS: Leishmania infantum was detected in 125 (6.4%) of 1961 dogs tested between 4 January 2006 and 22 May 2019, of which 10 (8%) were foxhounds and 115 (92%) were nonfoxhound breeds. Travel history available for 69 (55%) dogs showed 60 (86.9%) dogs had traveled outside of the US or Canada. Nine (13%) dogs had not traveled outside of the US or Canada, 5 of which were nonfoxhounds. CONCLUSIONS AND CLINICAL IMPORTANCE: The majority of L. infantum cases were detected in nonfoxhounds, many of which had traveled to L. infantum-endemic countries, and several nonfoxhound breeds had no travel history. Leishmania surveillance should be considered for dogs that return from L. infantum-endemic regions to monitor emergence of this zoonotic disease in the US and Canada.

Bartonella Associated Cutaneous Lesions (BACL) in People with Neuropsychiatric Symptoms.

Bartonella species are globally important emerging pathogens that were not known to infect animals or humans in North America prior to the human immunodeficiency virus (HIV) epidemic. Ongoing improvements in diagnostic testing modalities have allowed for the discovery of Bartonella species (spp.) DNA in blood; cerebrospinal fluid; and the skin of patients with cutaneous lesions, fatigue, myalgia, and neurological symptoms. We describe Bartonella spp. test results for participants reporting neuropsychiatric symptoms, the majority of whom reported the concurrent development of cutaneous lesions. Study participants completed a medical history, a risk factor questionnaire, and provided cutaneous lesion photographs. Bartonella spp. serology and Bartonella alpha proteobacteria enrichment blood culture/PCR were assessed. Within a 14-month period, 33 participants enrolled; 29/33 had serological and/or PCR evidence supporting Bartonella spp. infection, of whom 24 reported concurrent cutaneous lesions since neuropsychiatric symptom onset. We conclude that cutaneous lesions were common among people reporting neuropsychiatric symptoms and Bartonella spp. infection or exposure. Additional studies, using sensitive microbiological and imaging techniques, are needed to determine if, or to what extent, Bartonella spp. might contribute to cutaneous lesions and neuropsychiatric symptoms in patients.

Detection of Bartonella spp. in dogs after infection with Rickettsia rickettsii.

BACKGROUND: Dynamics of infection by Bartonella and Rickettsia species, which are epidemiologically associated in dogs, have not been explored in a controlled setting. OBJECTIVES: Describe an outbreak investigation of occult Bartonella spp. infection among a group of dogs, discovered after experimentally induced Rickettsia rickettsii (Rr) infection. ANIMALS: Six apparently healthy purpose-bred Beagles obtained from a commercial vendor. METHODS: Retrospective and prospective study. Dogs were serially tested for Bartonella spp. and Rr using serology, culture, and PCR, over 3 study phases: 3 months before inoculation with Rr (retrospective), 6 weeks after inoculation with Rr (retrospective), and 8 months of follow-up (prospective). RESULTS: Before Rr infection, 1 dog was Bartonella henselae (Bh) immunofluorescent antibody assay (IFA) seroreactive and 1 was Rickettsia spp. IFA seroreactive. After inoculation with Rr, all dogs developed mild Rocky Mountain spotted fever compatible with low-dose Rr infection, seroconverted to Rickettsia spp. within 4-11 days, and recovered within 1 week. When 1 dog developed ear tip vasculitis with intra-lesional Bh, an investigation of Bartonella spp. infection was undertaken. All dogs had seroconverted to 1-3 Bartonella spp. between 7 and 18 days after Rr inoculation. Between 4 and 8 months after Rr inoculation, Bh DNA was amplified from multiple tissues from 2 dogs, and Bartonella vinsonii subsp. berkhoffii (Bvb) DNA was amplified from 4 of 5 dogs' oral swabs. CONCLUSIONS AND CLINICAL IMPORTANCE: Vector-borne disease exposure was demonstrated in research dogs from a commercial vendor. Despite limitations, our results support the possibilities of recrudescence of chronic subclinical Bartonella spp. infection after Rr infection and horizontal direct-contact transmission between dogs.

A retrospective study of vector-borne disease prevalence in dogs with proteinuria: Southeastern United States.

BACKGROUND: Proteinuria is a risk factor for progressive kidney injury in dogs. Enhanced understanding of potential associations between canine vector-borne diseases (CVBD) and proteinuria is needed. OBJECTIVES: To determine the proportion of evaluated proteinuric dogs exposed to ≥1 CVBD, including Babesia spp., Ehrlichia spp., spotted-fever group Rickettsia, Bartonella spp., Anaplasma spp., hemotropic Mycoplasma spp., Borrelia burgdorferi, and Dirofilaria immitis, and to determine if demographic or clinicopathologic differences exist between proteinuric dogs exposed to CVBD versus proteinuric dogs with no evidence of CVBD exposure. ANIMALS: Two-hundred nine proteinuric dogs, concurrently tested for CVBD, which were examined at a single academic veterinary hospital between January 2008 and December 2015. METHODS: Retrospective cross-sectional study. Demographic, clinicopathologic, and CVBD test results were extracted from medical records. A multivariable logistic regression model was used to assess associations between CVBD and selected variables. RESULTS: Based on serology and polymerase chain reaction testing, 34% of proteinuric dogs (72/209) were exposed to ≥1 CVBD. Exposure to Rickettsia spp. (19%), Ehrlichia spp. (12%), and B. burgdorferi (9%) were most common. The CVBD exposure was lower in dogs tested in autumn or spring, higher in intact dogs, and higher in dogs with lower serum albumin and higher serum creatinine concentrations. CONCLUSIONS AND CLINICAL IMPORTANCE: Exposure to CVBD, particularly exposure to Rickettsia spp., Ehrlichia spp., and B. burgdorferi was found in proteinuric dogs from the southeast United States. Additional controlled prospective studies examining a potential causal relationship between CVBD and proteinuria are warranted.