Michael R Lappin

Colorado State University, Fort Collins, CO, USA

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Publications (93)131.09 Total impact

  • Article: A flea and tick collar containing 10% imidacloprid and 4.5% flumethrin prevents flea transmission of Bartonella henselae in cats.
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    ABSTRACT: BACKGROUND: Bartonella henselae is transmitted amongst cats by Ctenocephalides felis and is associated with multiple clinical syndromes in cats and people. In a previous study, monthly spot-on administration of 10% imidacloprid/1% moxidectin was shown to block transmission of B. henselae amongst cats experimentally exposed to infected C. felis. The purpose of this study was to determine whether application of a flea and tick collar containing 10% imidacloprid and 4.5% flumethrin would lessen C. felis transmission of B. henselae amongst cats for 8 months. METHODS: Specific pathogen free cats (n = 19) were housed in three adjoining enclosures that were separated by mesh to allow C. felis to pass among groups but prevent cats in different enclosures from contacting one another. One group of 4 cats was inoculated intravenously with B. henselae and after infection was confirmed in all cats based on positive PCR assay results, the cats were housed in the middle enclosure. The B. henselae infected cat group was flanked by a group of 8 cats that had the collar placed and maintained for the duration of the study and a group of 7 cats that were not treated. Ctenocephalides felis (50 males and 50 females) raised in an insectary were placed on each of the 4 cats in the B. henselae infected group monthly for 7 applications and then every 2 weeks for 4 applications starting the day the collar was applied. Blood was collected from all cats weekly for Bartonella spp. PCR, serology and culture. RESULTS: While side-effects associated with the collars were not noted, persistent fever necessitating enrofloxacin therapy occurred in two of the untreated cats. While B. henselae infection was ultimately confirmed in 4 of 7 of the untreated cats, none of the cats with collars became infected (P = 0.026). CONCLUSIONS: In this study design, use of a collar containing 10% imidacloprid and 4.5% flumethrin was well tolerated and prevented C. felis transmission of B. henselae amongst cats for 8 months.
    Parasites & Vectors 01/2013; 6(1):26. · 2.94 Impact Factor
  • Article: Development of a broad-range quantitative polymerase chain reaction assay to detect and identify fungal DNA in equine endometrial samples.
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    ABSTRACT: Objective-To develop a broad-range 28S ribosomal DNA quantitative PCR (qPCR) assay for detection of fungal DNA in equine endometrial samples. Sample-12 fungal samples from a clinical diagnostic laboratory and 29 samples obtained from 17 mares. Procedures-The qPCR assay was optimized with commercially acquired fungal organisms and validated with samples obtained from the clinical diagnostic laboratory. Subsequently, 29 samples from 17 mares suspected of having fungal endometritis were evaluated via the qPCR assay and via traditional fungal culture and endometrial cytology. Amplicons from the qPCR assay were subjected to genetic sequencing to identify the organisms. Results-The qPCR assay theoretically had a detection threshold of 2 organisms of Candida albicans. Fungal DNA was amplified from all 12 fungal samples from the commercial diagnostic laboratory. Fungal identification by use of genetic sequencing was successful for 34 of 36 amplicons from the 12 samples assayed. A fungal agent was identified via qPCR assay and genetic sequencing in all 12 samples; in contrast, a fungal agent was identified in only 8 of 12 samples via standard fungal culture and biochemical analysis. The qPCR assay detected fungal DNA in samples from 12 of 17 mares suspected of having fungal endometritis. Conclusions and Clinical Relevance-A rapid, sensitive, and repeatable qPCR assay was developed for detection of fungal DNA from equine endometrial samples. The qPCR may prove to be clinically useful as an adjunct to microbial culture and cytologic examination to provide identification of fungal organisms in a timely manner.
    American Journal of Veterinary Research 01/2013; 74(1):161-5. · 1.27 Impact Factor
  • Article: Feline bartonellosis: we're just scratching the surface.
    Edward B Breitschwerdt, Michael R Lappin
    Journal of feline medicine and surgery. 09/2012; 14(9):609-10.
  • Article: Comparisons of mammalian Giardia duodenalis assemblages based on the β-giardin, glutamate dehydrogenase and triose phosphate isomerase genes.
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    ABSTRACT: The objective of this study was to determine and compare the assemblages of Giardia duodenalis isolated from mammalian fecal samples using the β-giardin (bg), glutamate dehydrogenase (gdh) and triosephosphate isomerase (tpi) genes. A total of 202 samples, either submitted to the Veterinary Diagnostic Laboratory (Parasitology) at Colorado State University or part of ongoing research studies, were typed. A subset of 50 dog samples were also assessed by the tpi-D-specific primers. Of these, 183 were from dogs, 13 were from cats, two were from llamas, and one each was from a calf, an alpaca, a sheep, and a horse. The majority of the dogs (171 of 183 isolates) in this study were infected with only dog-adapted Assemblage C or D. The tpi-D-specific primers confirmed that 28 of the samples that typed as Assemblage D by the bg and gdh genes were also Assemblage D by the tpi-D-specific primers. Only 12 isolates were Assemblage A alone or Assemblage A and Assemblage C or D. Of the 13 cat isolates, seven were Assemblage F, two were Assemblage D, three were Assemblage A and 1 contained both Assemblages C and D. The calf isolate was Assemblage E (gdh, tpi) and the alpaca (bg, gdh), llamas (gdh), sheep (bg, gdh, tpi) and horse (tpi) isolates were all Assemblage A. When the assemblage could be determined for more than one gene, 91 of 117 dog isolates gave consistent results and 8 of 9 cat isolates gave consistent results.
    Veterinary Parasitology 05/2012; 189(2-4):182-8. · 2.58 Impact Factor
  • Article: Prevalence of methicillin-resistant staphylococci in northern Colorado shelter animals.
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    ABSTRACT: Methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus pseudintermedius (MRSP) have been recognized as significant pathogens in veterinary medicine. There have been documented cases of MRSA infection and colonization in veterinary critical care units, in veterinary personnel, and in equine and feline patients. To date, there have been no studies examining the prevalence of MRSA or MRSP colonization of cats and dogs in animal shelters in the United States. The purpose of the current study was to determine the prevalence of MRSA and MRSP in cats and dogs in a northern Colorado animal shelter. Samples were collected from 200 cats and 200 dogs in an open admission shelter. Each species was divided into 2 smaller groups: 100 dogs or cats housed in the stray ward and 100 dogs or cats housed in the adoption area. Samples were evaluated for the prevalence of MRSA or MRSP, which was verified through aerobic culture and Kirby-Bauer agar disc diffusion to confirm antimicrobial sensitivity. Results revealed MRSA in 0.5% of cat samples, MRSA in 0.5% of dog samples, and MRSP in 3% of dog samples. These results are consistent with previously published prevalence rates for these 2 organisms in non-shelter populations of dogs and cats, indicating that cats and dogs from this Colorado shelter do not appear to pose any greater risk to the public than do cats and dogs in the general pet population.
    Journal of veterinary diagnostic investigation: official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc 09/2011; 23(5):947-50. · 1.21 Impact Factor
  • Article: Prevalence of Giardia and Cryptosporidium species in dog park attending dogs compared to non-dog park attending dogs in one region of Colorado.
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    ABSTRACT: Dog parks are very popular in urban areas, but there are no current studies attempting to correlate visits to dog parks and risk of colonization by enteric parasites. The purpose of this study was to determine whether dog park visitation is associated with an increased prevalence of enteric parasites or an increase in prevalence of gastrointestinal signs in dogs in northern Colorado. Feces from dogs owned by veterinary students or Veterinary Teaching Hospital staff members were submitted with a completed survey form detailing dog park attendance rates, fecal character scores, and other clinical information. Feces were examined microscopically for parasites after sugar centrifugation, for Giardia spp. cysts and Cryptosporidium spp. oocysts by a commercially available immunofluorescence assay (FA) and the FA positive samples were genotyped after PCR amplification. The Giardia assemblages were determined using the glutamate dehydrogenase (GDH) β-giardin and triose phosphate isomerase (TPI) genes and the Cryptosporidium species were determined using the heat shock protein-70 gene. A total of 129 fecal samples were assayed; 66 were from dog park attending dogs and 63 were from non-dog park-attending dogs. The overall parasite prevalence rate was 7.0% (9 of 129 samples). Dog park attending dogs were more likely to be positive for Giardia or Cryptosporidium than non-dog park-attending dogs (p=0.0279), but there was no association of gastrointestinal signs with dog park attendance or with fecal flotation or FA results. The five Giardia isolates were assemblage C and/or D and the one Cryptosporidium isolate was Ctenocephalides canis.
    Veterinary Parasitology 08/2011; 184(2-4):335-40. · 2.58 Impact Factor
  • Article: Prevalence of selected zoonotic and vector-borne agents in dogs and cats in Costa Rica.
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    ABSTRACT: To estimate the prevalence of enteric parasites and selected vector-borne agents of dogs and cats in San Isidro de El General, Costa Rica, fecal and serum samples were collected from animals voluntarily undergoing sterilization. Each fecal sample was examined for parasites by microscopic examination after fecal flotation and for Giardia and Cryptosporidium using an immunofluorescence assay (IFA). Giardia and Cryptosporidium IFA positive samples were genotyped after PCR amplification of specific DNA if possible. The seroprevalence rates for the vector-borne agents (Dirofilaria immitis, Borrelia burgdorferi, Ehrlichia canis, and Anaplasma phagocytophilum) were estimated based on results from a commercially available ELISA. Enteric parasites were detected in samples from 75% of the dogs; Ancylostoma caninum, Trichuris vulpis, Giardia, and Toxocara canis were detected. Of the cats, 67.5% harbored Giardia spp., Cryptosporidium spp., Ancylostoma tubaeforme, or Toxocara cati. Both Cryptosporidium spp. isolates that could be sequenced were Cryptosporidium parvum (one dog isolate and one cat isolate). Of the Giardia spp. isolates that were successfully sequenced, the 2 cat isolates were assemblage A and the 2 dog isolates were assemblage D. D. immitis antigen and E. canis antibodies were identified in 2.3% and 3.5% of the serum samples, respectively. The prevalence of enteric zoonotic parasites in San Isidro de El General in Costa Rica is high in companion animals and this information should be used to mitigate public health risks.
    Veterinary Parasitology 07/2011; 183(1-2):178-83. · 2.58 Impact Factor
  • Article: Prevalence of Bartonella species, haemoplasmas and Toxoplasma gondii in cats in Scotland.
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    ABSTRACT: The objective of this study was to determine the prevalence rates for select infectious agents of cats presented to the Royal (Dick) School of Veterinary Studies at the University of Edinburgh, Scotland. Whole blood, serum, and oral mucosal and nail bed swabs were collected. While Ehrlichia species, Anaplasma species or Rickettsia felis DNA were not amplified from any cat, 44.2% of the cats had evidence of infection or exposure to either a Bartonella species (15.3% were seropositive and 5.8% polymerase chain reaction (PCR) positive), a haemoplasma (28.6% PCR positive), and/or Toxoplasma gondii (19.2% seropositive). No Bartonella species DNA was amplified from the nail or oral mucosal swabs despite a 5.8% amplification rate from the blood samples. This finding likely reflects the absence of Ctenocephalides felis infection from our study population, as this organism is a key component for Bartonella species translocation in cats. The results from this study support the use of flea control products to lessen exposure of cats (and people) to Bartonella species and support discouraging the feeding of raw meat to cats and preventing them from hunting to lessen T gondii infection.
    Journal of feline medicine and surgery. 05/2011; 13(8):553-7.
  • Article: Efficacy of a single dose of an otic ivermectin preparation or selamectin for the treatment of Otodectes cynotis infestation in naturally infected cats.
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    ABSTRACT: Otodectes cynotis infestation is common in kittens housed in crowded environments like animal shelters. It is unknown how rapidly O cynotis is killed within the first 72h of treatment with currently available products. Kittens ≥4 weeks of age with live O cynotis in both ears (AU) were administered 0.5ml of 0.01% ivermectin otic suspension (Acarexx; Idexx Pharmaceuticals) once, AU or selamectin (Revolution; Pfizer Animal Health) once, on the skin following the manufacturer's instructions. Repeat microscopic examination was performed on individual ears based on a randomization schedule during the 72h after treatment. There was no evidence of toxicity with either drug and administration of 0.01% ivermectin significantly reduced the time to live mite-free status compared to selamectin. Both drugs have an effect against O cynotis as early as 10-12h after administration with an increasing effect over time.
    Journal of feline medicine and surgery. 04/2011; 13(8):622-4.
  • Article: Results of molecular diagnostic assays targeting feline herpesvirus-1 and feline calicivirus in adult cats administered modified live vaccines.
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    ABSTRACT: In this pilot study, 12 adult, gang-housed cats that were known to be previously exposed (n=12) to feline herpesvirus-1 (FHV-1) and/or vaccinated against (n=2) feline calicivirus (FCV) and FHV-1 were randomly assigned to one of two groups of six cats each. Nasal and pharyngeal samples were collected from each cat on days -7, -3, and 0 prior to vaccination and on days 3, 7, 10, 14, 17, 21, and 28 after vaccination with an FHV-1, FCV, and panleukopenia (FVRCP) vaccine developed for intranasal (six cats) or parenteral (six cats) use. FHV-1 DNA was amplified from 1/12 cats (1/69 samples; 1.4%) prior to vaccination and 2/12 cats after vaccination (2/154 samples; 1.3%). FCV RNA was amplified from 2/12 cats (2/69 samples; 2.9%) prior to vaccination and 7/12 cats (12/154 samples; 7.8%) after vaccination. Positive molecular diagnostic assay results for FHV-1 and FCV were uncommon prior to or after vaccination in these cats.
    Journal of feline medicine and surgery. 03/2011; 13(8):541-5.
  • Article: Prevalence of infectious diseases in cats and dogs rescued following Hurricane Katrina.
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    ABSTRACT: To determine the prevalence of infectious diseases of animal and zoonotic importance in cats and dogs rescued and transferred from the Gulf Coast region following Hurricane Katrina. Cross-sectional study. 414 dogs and 56 cats rescued and transferred from the Gulf Coast region within 4 months after the hurricane. EDTA-anticoagulated blood and serum samples were tested via PCR and serologic assays for infectious diseases. In dogs, prevalence was highest for anti-West Nile virus (WNV) antibodies (218/390 [55.9%]), Dirofilaria immitis antigen (195/400 [48.8%]), anti-Toxoplasma gondii antibodies (92/366 [25.1%]), and hemotropic mycoplasma DNA (40/345 [11.9%]). The DNA of Bartonella spp, Ehrlichia spp, or Babesia spp or anti-canine influenza virus antibodies were identified in < 2% of dogs. In cats, prevalence was highest for antibodies against Bartonella spp and DNA of Bartonella spp combined (49/55 [89.1 %]), anti-T gondii antibodies (13/55 [23.6%]), hemotropic mycoplasma DNA (5/47 [10.6%]), anti-WNV antibodies (5/48 [10.4%]), D immitis antigen (4/50 [8.0%]), and anti-FIV antibodies (4/56 [7.1%]). A total of 308 (74.4%) dogs and 52 (92.9%) cats had evidence of previous or current vector-borne infections. Cats and dogs rescued from the disaster region had evidence of multiple infectious diseases. The dispersal of potentially infectious animals to other regions of North America where some infections were not typically found could have contributed to new geographic ranges for these organisms or to underdiagnosis in affected animals because of a low index of suspicion in regions with low disease prevalence.
    Journal of the American Veterinary Medical Association 02/2011; 238(3):311-7. · 1.79 Impact Factor
  • Article: Leishmaniasis in a dog native to Colorado.
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    ABSTRACT: A 1-year-old 32.5-kg (71.5-lb) sexually intact male foxhound-Treeing Walker Coonhound cross was evaluated because of a 2.5-month history of dermatologic lesions, weight loss, and diarrhea. Physical examination revealed muscle wasting, lymphadenopathy, and multifocal pruritic dermatologic lesions of alopecia, thickening, erythema, and follicular casting. Hematologic and serum biochemical analyses revealed nonregenerative anemia, mono-cytosis, hypercalcemia, hyperproteinemia, and hyperglobulinemia. Proteinuria was identified on urinalysis. Hepatomegaly, splenomegaly, and diffuse abdominal lymphadenomegaly were detected on abdominal ultrasonography. A diagnosis of leishmaniasis was confirmed by ELISA detection of serum antibodies against Leishmania spp, a high serum indirect fluorescent antibody titer (1:1,024) against Leishmania infantum, amplification of Leishmania DNA on PCR assay of a whole blood sample and a lymph node aspirate, and histologic identification of suspected Leishmania amastigotes in skin specimens. In addition, the dog had a low CD4+:CD8+ lymphocyte ratio of 1:1. The dog was euthanized because of the severity of leishmaniasis and poor prognosis. This dog was from a litter of 10 puppies that included 4 stillborn puppies, 2 puppies that died as neonates, and 1 littermate that was euthanized at 1 year of age because of a high serum antibody titer against Leishmania spp. Eventually the foxhound dam was euthanized because of a high serum antibody titer against Leishmania spp. The dog had been raised with an unaffected littermate, its sire, and an unrelated Treeing Walker Coonhound female that were seronegative for Leishmania infection. Although vertical disease transmission was suspected, it is possible that L infantum is now endemic in Colorado. Leishmaniasis should be considered in dogs with scaly dermatoses.
    Journal of the American Veterinary Medical Association 12/2010; 237(11):1288-91. · 1.79 Impact Factor
  • Article: Bartonella species, feline herpesvirus-1, and Toxoplasma gondii PCR assay results from blood and aqueous humor samples from 104 cats with naturally occurring endogenous uveitis.
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    ABSTRACT: Toxoplasma gondii, Bartonella henselae and feline herpesvirus-1 (FHV-1) have been implicated as causative agents in feline uveitis. The usefulness of serum and aqueous humor (AH) antibody testing for these agents is limited as antibodies can be detected in both healthy cats and cats with uveitis. Very few studies using polymerase chain reaction (PCR) assays to amplify organism DNA from samples from cats with uveitis have been performed. In this study, assays to detect T gondii antibodies, feline leukemia virus antigen, feline immunodeficiency virus antibody, and Bartonella species antibodies were performed on serum and PCR assays for amplification of T gondii, Bartonella species, and FHV-1 DNA were performed on blood and AH samples from 104 cats with endogenous uveitis and 19 healthy cats. Results suggest the addition of the PCR assay to the diagnostic work-up for cats with uveitis will increase the detection of T gondii and FHV-1; however, the diagnostic usefulness of these additional data is not clear.
    Journal of feline medicine and surgery. 12/2010; 12(12):923-8.
  • Article: Molecular diagnostic assays for infectious diseases in cats.
    Julia K Veir, Michael R Lappin
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    ABSTRACT: With the advent of more accessible polymerase chain reaction panels, the use of molecular techniques for the detection of infectious organisms has become more routine in veterinary medicine. The use of molecular diagnostics is best reserved for the detection of organisms that are difficult to detect or identify expediently. In this article, the fundamentals of molecular techniques are reviewed along with an examination of specific feline infectious diseases in which diagnosis via molecular techniques is advantageous.
    Veterinary Clinics of North America Small Animal Practice 11/2010; 40(6):1189-200. · 1.64 Impact Factor
  • Article: Detection of bacterial and viral organisms from the conjunctiva of cats with conjunctivitis and upper respiratory tract disease.
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    ABSTRACT: A variety of pathogens are involved in conjunctivitis in cats. In this study, the prevalence of feline herpesvirus (FHV), Chlamydophila felis, mycoplasmas, and aerobic bacteria on the conjunctival surface of cats with conjunctivitis and upper respiratory tract disease was investigated by polymerase chain reaction (PCR), immunofluorescent assay (IFA), and aerobic bacterial culture of ocular swabs. Forty-one cats were included of which 37 were found to be infected with an ocular organism. Single and multiple infections were present in 15 and 22 cats, respectively. FHV, mycoplasmas, and C felis were detected by PCR in 11 (27%), 20 (49%), and 23 (56%) cats, respectively. IFA detected 10 cats as positive for C felis. Mycoplasma felis, Mycoplasma canadense, Mycoplasma cynos, Mycoplasma gateae, Mycoplasma lipophilum, and Mycoplasma hyopharyngis were identified by genetic sequencing. The most common aerobic bacteria cultured included Staphylococcus species, Streptococcus species and Micrococcus species. The prevalence of mycoplasmas in cats with conjunctivitis was higher than previously reported, and four of the Mycoplasma species have not been described in cats so far.
    Journal of feline medicine and surgery. 10/2010; 12(10):775-82.
  • Article: Prevalence of select infectious agents in inflammatory aural and nasopharyngeal polyps from client-owned cats.
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    ABSTRACT: Benign, inflammatory polyps may affect the nasopharynx and auditory canal of cats. It has been proposed that inflammation induced by infectious disease agents could trigger polyp formation. The objective of this pilot study was to determine the prevalence of feline herpesvirus-1 (FHV-1), feline calicivirus (FCV), Mycoplasma species, Bartonella species and Chlamydophila felis nucleic acids in polyp tissues collected from 30 clinically affected cats. Samples collected from the tympanic bulla from 12 clinically normal cats were also assayed. DNA or RNA of some of the target agents were amplified from samples from 25% of normal cats and 33% of affected cats; however, statistical associations were not detected for individual agent results or grouped results. The study documents that common oropharyngeal or blood borne agents can be detected in the tympanic bullae of normal cats. Failure to consistently amplify RNA or DNA of the select agents from polyp tissues suggests the agents studied were not directly associated with the pathogenesis of this syndrome in the cats tested. Alternately, the inflammatory response may have cleared microbial nucleic acids to undetectable levels by the time of sample collection.
    Journal of feline medicine and surgery. 10/2010; 12(10):769-74.
  • Article: Comparison of urine dipstick, sulfosalicylic acid, urine protein-to-creatinine ratio, and species-specific ELISA methods for detection of albumin in urine samples of cats and dogs.
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    ABSTRACT: To evaluate the use of dipstick, sulfosalicylic acid (SSA), and urine protein-to-creatinine ratio (UP:C) methods for use in detection of canine and feline albuminuria. Evaluation study. 599 canine and 347 feline urine samples. Urine was analyzed by use of dipstick, SSA, and UP:C methods; results were compared with those for a species-specific ELISA to determine sensitivity, specificity, positive predictive value (PPV), negative predictive value, and positive and negative likelihood ratios. Positive results for dipstick and SSA tests (trace reaction or greater) in canine urine had moderate specificity (dipstick, 81.2%; SSA, 73.3%) and poor PPV (dipstick, 34.0%; SSA, 41.8%). Values improved when stronger positive results (>or= 2+) for the dipstick and SSA tests were compared with ELISA results (specificity, 98.9% and 99.0% for the urine dipstick and SSA tests, respectively; PPV, 90.7% and 90.2% for the dipstick and SSA tests, respectively). Data obtained for cats revealed poor specificity (dipstick, 11.0%; SSA, 25.4%) and PPV (dipstick, 55.6%; SSA, 46.9%). Values improved slightly when stronger positive test results (>or= 2+) were used (specificity, 80.0% and 94.2% for the dipstick and SSA tests, respectively; PPV, 63.5% and 65.2% for the dipstick and SSA tests, respectively). The UP:C had high specificity for albuminuria in dogs and cats (99.7% and 99.2%, respectively) but low sensitivity (28.7% and 2.0%, respectively). Caution should be used when interpreting a positive test result of a dipstick or SSA test for canine or feline albuminuria.
    Journal of the American Veterinary Medical Association 04/2010; 236(8):874-9. · 1.79 Impact Factor
  • Article: Evaluation of topical application of 10% imidacloprid-1% moxidectin to prevent Bartonella henselae transmission from cat fleas.
    Christina A Bradbury, Michael R Lappin
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    ABSTRACT: To determine whether monthly topical administration of a combination of 10% imidacloprid and 1% moxidectin would lessen flea (Ctenocephalides felis) transmission of Bartonella henselae among cats. Controlled trial. 18 specific pathogen-free cats housed in 3 groups of 6. 3 enclosures were separated by mesh to allow fleas to pass among groups yet prevent cats from contacting one another. One group was inoculated IV with B henselae, and after infection was confirmed, the cats were housed in the middle enclosure. This infected group was flanked by a group that was treated topically with 10% imidacloprid-1% moxidectin monthly for 3 months and by an untreated group. On days 0, 15, 28, and 42, 100 fleas/cat were placed on each of the 6 cats in the B henselae-infected group. Blood samples were collected from all cats weekly for detection of Bartonella spp via PCR assay, bacterial culture, and serologic assay. B henselae infection was confirmed in the cats infected IV and in all untreated cats after flea exposure; none of the cats treated with the imidacloprid-moxidectin combination became infected. In this setting, monthly topical administration of 10% imidacloprid-1% moxidectin reduced flea infestation, compared with infestation in untreated cats, and thus prevented flea transmission of B henselae to treated cats. Regular monthly use of this flea control product in cats may lessen the likelihood of humans acquiring B henselae infection.
    Journal of the American Veterinary Medical Association 04/2010; 236(8):869-73. · 1.79 Impact Factor
  • Article: Association of Wolbachia with heartworm disease in cats and dogs.
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    ABSTRACT: Although the presence of adult Dirofilaria immitis in the pulmonary arteries and its associated arteritis and thromboembolic disease can explain some of the manifestations of canine and feline heartworm disease, the cause of other findings remains unclear. Cats with D. immitis antibodies but lacking adult parasites in the pulmonary arteries frequently develop histological lesions of the airways, resulting in a condition termed Heartworm-Associated Respiratory Disease. All D. immitis parasites harbor Wolbachia pipientis bacteria and D. immitis-infected animals can have circulating Wolbachia antibodies and pro-inflammatory Wolbachia antigens (WSP) deposited in tissues. Little is known about the role that Wolbachia plays in lung disease of animals naturally infected with D. immitis. The purpose of this study was to determine the contribution of Wolbachia to the pathogenesis of natural heartworm disease in cats and dogs. We hypothesized that animals having sufficient Wolbachia burden to be detected in lung tissue by immunohistochemistry and/or polymerase chain reaction (PCR) would have more severe pulmonary disease than those with bacteria below the limits of detection. We further hypothesized that animals that were immunoreactive to pro-inflammatory WSP would have more severe pulmonary lesions than those that were seronegative for WSP antibodies. Blood and lung tissue samples were collected from cats and dogs representing three different D. immitis infection statuses: heartworm-free, heartworm-exposed, heartworm-infected. There was a positive but weak correlation between the magnitude of D. immitis antibody titers and WSP titers in cats (r=0.57, p<0.001) and in dogs (r=0.39, p<0.001). Pulmonary lesions were more common in HW-infected animals than in HW-free animals. Pulmonary arteriolar occlusion was more common in HW-infected cats (57%; p=0.003) than in HW-infected dogs (17%). Although pulmonary lesions were most common in HW-infected animals, there was no clear additive effect when either Wolbachia DNA/WSP was detected in lung tissue or when circulating Wolbachia antibodies were detected. There were no significant differences in the magnitude of pulmonary lesion scores within each HW-infection status group regardless of whether Wolbachia DNA/WSP or antibodies were detected. The relationship between Wolbachia and lung pathology in heartworm-infected animals remains to be determined. The lack of clear evidence for a role of Wolbachia in heartworm disease creates a dilemma for veterinarians treating animals in D. immitis-endemic areas. Although the indiscriminant use of antibiotics should be avoided, many clinicians prescribe doxycycline based on the favorable responses observed in human filarial diseases and promising results from the first published studies of doxycycline use in D. immitis-infected dogs.
    Veterinary Parasitology 02/2010; 170(1-2):50-60. · 2.58 Impact Factor
  • Article: Bartonellosis: an emerging infectious disease of zoonotic importance to animals and human beings.
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    ABSTRACT: To provide a review of clinically relevant observations related to Bartonella species as emerging pathogens in veterinary and human medicine. Literature as cited in PubMed and as generated by each of the authors who have contributed to various aspects of the clinical understanding of bartonellosis. Important historical and recent publications illustrating the evolving role of animal reservoirs as a source of human infection. Comprehensive review of the veterinary literature. In addition to inducing life-threatening illnesses, such as endocarditis, myocarditis, and meningoencephalitis and contributing to chronic debilitating disease, such as arthritis, osteomyelitis, and granulomatous inflammation in cats, dogs, and potentially other animal species; pets and wildlife species can serve as persistently infected reservoir hosts for the transmission of Bartonella spp. infection to veterinary professionals and others with direct animal contact.
    Journal of veterinary emergency and critical care (San Antonio, Tex. : 2001). 02/2010; 20(1):8-30.