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.

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.

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.

Effect of a mindfulness exercise on stress in veterinary students performing surgery.

OBJECTIVE: To determine students' stress while performing surgery and evaluate the ability of a mindfulness intervention to reduce this stress. STUDY DESIGN: Quasi-experimental design. SAMPLE POPULATION: Eighteen fourth-year DVM program students (n = 9 student/group). METHODS: Utilizing a quasi-experimental design, students were randomly assigned to a control or treatment group. The treatment group performed a 5-minute breathing (mindfulness) exercise immediately prior to performing surgery. Each student provided 3 samples of saliva, at time 0, at 10 minutes before surgery, and at 10 minutes after surgery. Students' salivary cortisol and α-amylase levels were compared between groups. Students' self-reported mood measures were also correlated to levels of salivary biomarkers. RESULTS: Cortisol and α-amylase levels of students in both groups greatly exceeded normative reference groups (>90th percentile) prior to surgery and diminished to average levels (50th-60th percentile) after surgery but did not differ between groups at any time point. Immediately prior to surgery when stress values were likely to peak, salivary α-amylase levels decreased approximately 30 U/L units for students in the treatment group compared with an increase of approximately 10 U/L units for students in the control group. Students in the treatment group reported being more calm (mean [M] 2.67, SD 1.03, d = 0.75) and relaxed (M 2.33, SD 1.51, d = 0.90) than students in the control group (M 3.44, SD 1.01 and M 3.44, SD 0.88, respectively). CONCLUSION: This study provides some evidence that the mindfulness intervention temporarily decreased stress levels and improved students' sense of calmness and relaxation immediately before operating on a live animal. CLINICAL IMPACT: Students who are experiencing less stress may be less likely to commit a medical error and negatively impact animal health. This study, the first of its kind in veterinary surgery, may serve as a model for related future studies.

Use of single-dose oral gabapentin to attenuate fear responses in cage-trap confined community cats: a double-blind, placebo-controlled field trial.

Objectives This double-blind, placebo-controlled study evaluated the safety and efficacy of single-dose oral gabapentin administered for the attenuation of fear responses in cage-trap confined community cats. Methods Community cats presented in cage traps for trap-neuter-return (TNR) were recruited and screened for inclusion. Each enrolled cat was randomly assigned and administered one of three equal-volume, single-dose treatments: placebo, low-dose gabapentin (50 mg) or high-dose gabapentin (100 mg). At baseline, 1, 2, 3 and 12 h post-administration, a single, blinded observer scored each cat for signs of fear and sedation using published paradigms, calculated the respiratory rate and documented any observable facial injuries. Results Fifty-three cats met the inclusion criteria and completed the study. Cat stress score (a measure of fear) was lower in cats that received gabapentin (50 or 100 mg) than in cats that received placebo (50 mg: P = 0.027; 100 mg: P = 0.029), with the greatest reduction at 2 h post-treatment ( P = 0.0007). Respiratory rates did not differ between treatment groups. There was no difference in sedation scores between the groups ( P = 0.86) at any time point ( P = 0.09). Cat facial injuries did not vary by treatment group or over time. No adverse effects were detected specific to gabapentin administration. At 1 h, hypersalivation was observed in four cats across all treatment groups. All cats recovered from surgery and anesthesia uneventfully. Conclusions and relevance This study supports the hypothesis that 50 mg or 100 mg gabapentin (9.2-47.6 mg/kg per cat) reduces fear responses in confined community cats without measurable sedation over 3 h post-administration vs placebo. Gabapentin treatment was well tolerated in this population of cats. Further studies are recommended to investigate the use of oral gabapentin earlier in the TNR process, such as immediately after trapping or prior to transport for the prevention of confinement-related injuries.

Diagnostic accuracy of a rapid immunoassay for point of-care detection of urinary tract infection in dogs.

OBJECTIVE: To determine the diagnostic accuracy of a rapid immunoassay (RIA) for point-of-care detection of urinary tract infection (UTI) of dogs, compared with criterion-referenced diagnosis with bacterial culture. SAMPLE: 200 urine samples obtained from dogs and submitted to a veterinary microbiology diagnostic laboratory for routine bacterial culture and antimicrobial susceptibility determination. PROCEDURES: Samples were evaluated by use of quantitative bacterial culture and the RIA. Sensitivity, specificity, and positive and negative predictive values of the RIA were calculated; results of bacterial culture were the criterion-referenced outcome. A κ statistic was calculated to determine agreement between bacterial culture and RIA results. RESULTS: 56 of 200 (28%) urine samples had positive results for bacterial growth by use of culture methods; there were 38 (19%) positive results likely to be associated with bacterial UTI on the basis of sample collection method and bacterial concentration. Sensitivity and specificity of the RIA for detecting samples likely to be associated with UTI (≥ 1,000 CFUs/mL) were 97.4% and 98.8%, respectively. The positive and negative predictive values of the RIA for bacterial cultures with likely UTI were 0.949 and 0.994, respectively. Agreement between bacterial culture and RIA outcome for UTI was substantial (weighted κ, 0.718). CONCLUSIONS AND CLINICAL RELEVANCE: The RIA test evaluated in this study accurately detected UTI of dogs, compared with detection with the criterion-referenced bacterial culture method. Use of this point-of-care RIA could allow clinicians to diagnose UTI at the time of a patient visit and provide information useful for immediately initiating empirical antimicrobial treatment.