Michael R. Lappin

Bartonellosis: an emerging infectious disease of zoonotic importance to animals and human beings.

OBJECTIVE To provide a review of clinically relevant observations related to Bartonella species as emerging pathogens in veterinary and human medicine. DATA SOURCES 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. HUMAN DATA SYNTHESIS Important historical and recent publications illustrating the evolving role of animal reservoirs as a source of human infection. VETERINARY DATA SYNTHESIS Comprehensive review of the veterinary literature. CONCLUSIONS 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.

Prevalence of infectious diseases in feral cats in Northern Florida.

Objectives of this study were to determine prevalence of infection in feral cats in Northern Florida with a select group of infectious organisms and to determine risk factors for infection. Blood samples or sera from 553 cats were tested with a panel of antibody, antigen or PCR assays. Male cats were at higher risk for FIV, Mycoplasma haemofelis, and M. haemominutum. Infection with either FeLV or FIV was associated with increased risk for coinfection with the other retrovirus, M. haemofelis, or M. haemominutum. Bartonella henselae had the highest prevalence and was the only organism that did not have any associated risk for coinfection with other organisms. Feral cats in this study had similar or lower prevalence rates of infections than those published for pet cats in the United States. Thus, feral cats assessed in this study appear to be of no greater risk to human beings or other cats than pet cats.

Prevalence of Bartonella species, haemoplasma species, Ehrlichia species, Anaplasma phagocytophilum, and Neorickettsia risticii DNA in the blood of cats and their fleas in the United States

Ctenocephalides felis were killed and collected from 92 cats in Alabama, Maryland, and Texas. The fleas and blood from the corresponding cat were digested and assessed in polymerase chain reaction assays that amplify DNA of Ehrlichia species, Anaplasma phagocytophilum, Neorickettsia risticii, Mycoplasma haemofelis, ‘Candidatus M haemominutum’ and Bartonella species. DNA consistent with B henselae, B clarridgeiae, M haemofelis, or ‘Candidatus M haemominutum’ was commonly amplified from cats (60.9%) and their fleas (65.2%). Results of this study support the recommendation to maintain flea control on cats in endemic areas.

Prevalence of Enteric Pathogens in Dogs of North-Central Colorado

To evaluate the prevalence of enteric pathogens in dogs of north-central Colorado, fecal samples were obtained from client-owned dogs presented to the Veterinary Teaching Hospital at Colorado State University for evaluation of acute small-bowel, large-bowel, or mixed-bowel diarrhea (n=71) and from age-matched, client-owned, healthy dogs (n=59). Infectious agents potentially associated with gastrointestinal disease were detected in 34 of 130 (26.1%) fecal samples. Agents with zoonotic potential were detected in feces from 21 (16.2%) of 130 dogs and included Giardia spp. (5.4%), Cryptosporidium parvum (3.8%), Toxocara canis (3.1%), Salmonella spp. (2.3%), Ancylostoma caninum (0.8%), and Campylobacter jejuni (0.8%). Positive test results occurred in dogs with or without gastrointestinal signs of disease. Dogs, particularly those in homes of immunocompromised humans, should be evaluated for enteric zoonotic agents.

Canine and feline blood donor screening for infectious disease.

Consensus Statements of the American College of Veterinary Internal Medicine (ACVIM) provide veterinarians with guidelines regarding the pathophysiology, diagnosis, or treatment of animal diseases. The foundation of the Consensus Statement is evidence‐based medicine, but if such evidence is conflicting or lacking, the panel provides interpretive recommendations on the basis of their collective expertise. The Consensus Statement is intended to be a guide for veterinarians, but it is not a statement of standard of care or a substitute for clinical judgment. Topics of statements and panel members to draft the statements are selected by the Board of Regents with input from the general membership. A draft prepared and input from Diplomates is solicited at the Forum and via the ACVIM Web site and incorporated in a final version. This Consensus Statement was approved by the Board of Regents of the ACVIM before publication.

Molecular Evidence Supporting Ehrlichia canis‐Like Infection in Cats

Currently, the pathogenic role of Ehrlichia canis in cats has been proposed predominantly on the basis of the serologic evidence of natural infection and the infrequent detection of morulae‐like structures within the cytoplasm of leukocytes in cats. The purpose of this report was to provide molecular evidence supporting E cams‐like infection in 3 cats that had clinical manifestations consistent with canine ehrlichiosis but lacked antibodies to E canis antigens. Serum from all 3 cats contained antinuclear antibodies (ANAs). The predominant disease manifestation was polyarthritis in 1 cat and bone marrow hypoplasia or dysplasia, accompanied by pancytopenia or anemia and thrombocytopenia, in 1 cat each. The alignment of E canis partial 16S ribosomal DNA (rDNA; 382 nucleotide positions), amplified from EDTA blood samples from each cat, was identical to each other and was identical to a canine isolate of E canis (GenBank accession number AF373613). In 1 cat, concurrent treatment with corticosteroids may have interfered with the therapeutic effectiveness of doxycycline for the elimination of E canis‐like infection. To further define the spectrum of ehrlichiosis in cats, polymerase chain reaction (PCR) testing may be necessary until serologic testing is thoroughly validated in experimentally or naturally infected cats. In addition, until E canis has been isolated from cats and several tissue culture isolates are available from disparate geographic regions for detailed comparative genetic study, the molecular evidence presented in this study supporting E canis‐like infection in cats must be interpreted with caution.

Three Pathogens in Sympatric Populations of Pumas, Bobcats, and Domestic Cats: Implications for Infectious Disease Transmission

Anthropogenic landscape change can lead to increased opportunities for pathogen transmission between domestic and non-domestic animals. Pumas, bobcats, and domestic cats are sympatric in many areas of North America and share many of the same pathogens, some of which are zoonotic. We analyzed bobcat, puma, and feral domestic cat samples collected from targeted geographic areas. We examined exposure to three pathogens that are taxonomically diverse (bacterial, protozoal, viral), that incorporate multiple transmission strategies (vector-borne, environmental exposure/ingestion, and direct contact), and that vary in species-specificity. Bartonella spp., Feline Immunodeficiency Virus (FIV), and Toxoplasma gondii IgG were detected in all three species with mean respective prevalence as follows: puma 16%, 41% and 75%; bobcat 31%, 22% and 43%; domestic cat 45%, 10% and 1%. Bartonella spp. were highly prevalent among domestic cats in Southern California compared to other cohort groups. Feline Immunodeficiency Virus exposure was primarily associated with species and age, and was not influenced by geographic location. Pumas were more likely to be infected with FIV than bobcats, with domestic cats having the lowest infection rate. Toxoplasma gondii seroprevalence was high in both pumas and bobcats across all sites; in contrast, few domestic cats were seropositive, despite the fact that feral, free ranging domestic cats were targeted in this study. Interestingly, a directly transmitted species-specific disease (FIV) was not associated with geographic location, while exposure to indirectly transmitted diseases – vector-borne for Bartonella spp. and ingestion of oocysts via infected prey or environmental exposure for T. gondii – varied significantly by site. Pathogens transmitted by direct contact may be more dependent upon individual behaviors and intra-specific encounters. Future studies will integrate host density, as well as landscape features, to better understand the mechanisms driving disease exposure and to predict zones of cross-species pathogen transmission among wild and domestic felids.

Effect of topical ophthalmic application of cidofovir on experimentally induced primary ocular feline herpesvirus-1 infection in cats

OBJECTIVE To evaluate the efficacy of twice-daily ophthalmic application of 0.5% cidofovir solution in cats with experimentally induced primary ocular feline herpesvirus-1 (FHV-1) infection. ANIMALS Twelve 6-month-old sexually intact male cats. PROCEDURES Cats were randomly assigned to either a treatment or control group. Ocular infection with FHV-1 was induced (day 0) in all cats via inoculation of both eyes with 10(4) plaque-forming units of a plaque-purified FHV-1 field strain. Twice daily for 10 days beginning on day 4 after virus inoculation, the treatment group received 1 drop of 0.5% cidofovir in 1% carboxymethylcellulose in both eyes, and the control group received 1 drop of 1% carboxymethylcellulose in both eyes. A standardized scoring method was used to evaluate clinical signs of FHV-1 infection in each cat once daily for 24 days. The amount of ocular viral shedding was assessed by use of a quantitative real-time PCR procedure every 3 days during the study period. Clinical scores and viral quantification were averaged over the pretreatment (days 0 to 3), treatment (days 4 to 14), and posttreatment (days 15 to 24) periods for each cat. RESULTS During the treatment period, clinical scores and amount of viral ocular shedding were significantly lower in the treatment group, compared with findings in the control group. CONCLUSIONS AND CLINICAL RELEVANCE Twice-daily application of 0.5% cidofovir solution in both eyes significantly decreased the amount of viral shedding and the severity of clinical disease in cats with experimentally induced ocular FHV-1 infection.

Toxoplasmosis and other intestinal coccidial infections in cats and dogs.

Toxoplasma gondii and related coccidians are intracellular protozoan parasites. Coccidia are obligate intracellular parasites normally found in the intestinal tract. Virtually all warm blooded animals, including humans are commonly infected with coccidians. This article reviews the diagnosis, treatment, and prevention of infections in cats and dogs related to Isospora spp, Toxoplasma gondii, and Neospora caninum. Much remains to be learned concerning the pathogenesis of clinical coccidiosis.

Effect of the Probiotic Enterococcus faecium SF68 on Presence of Diarrhea in Cats and Dogs Housed in an Animal Shelter

Background: Beneficial effects of probiotics have never been analyzed in an animal shelter. Hypothesis: Dogs and cats housed in an animal shelter and administered a probiotic are less likely to have diarrhea of ≥2 days duration than untreated controls. Animals: Two hundred and seventeen cats and 182 dogs. Methods: Double blinded and placebo controlled. Shelter dogs and cats were housed in 2 separate rooms for each species. For 4 weeks, animals in 1 room for each species was fed Enterococcus faecium SF68 while animals in the other room were fed a placebo. After a 1‐week washout period, the treatments by room were switched and the study continued an additional 4 weeks. A standardized fecal score system was applied to feces from each animal every day by a blinded individual. Feces of animals with and without diarrhea were evaluated for enteric parasites. Data were analyzed by a generalized linear mixed model using a binomial distribution with treatment being a fixed effect and the room being a random effect. Results: The percentage of cats with diarrhea ≥2 days was significantly lower (P= .0297) in the probiotic group (7.4%) when compared with the placebo group (20.7%). Statistical differences between groups of dogs were not detected but diarrhea was uncommon in both groups of dogs during the study. Conclusion and Clinical Importance: Cats fed SF68 had fewer episodes of diarrhea of ≥2 days when compared with controls suggests the probiotic may have beneficial effects on the gastrointestinal tract.