Prevalence of Bartonella species antibodies and Bartonella species DNA in the blood of cats with and without fever

Pradofloxacin for Treatment of Bartonella henselae in Experimentally Inoculated Cats

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

Treatment of a cat with presumed Bartonella henselae-associated immune-mediated hemolytic anemia, fever, and lymphadenitis

A 2.5‐year‐old castrated male cat presented with fever and marked generalized lymphadenopathy of 4‐months duration, despite treatment with amoxicillin‐clavulanate/marbofloxacin. Abnormalities were not detected on complete blood count, serum chemistry, and FIV/FeLV test apart from a borderline, non‐regenerative anemia. Peripheral lymph node fine needle aspirations revealed a marked increase in the percentage of intermediate‐ and lymphoblastic‐lymphocytes in addition to reactive macrophages. Three weeks after presentation, the cat developed a severe, regenerative, immune‐mediated hemolytic anemia (IMHA) which responded to immunosuppressive therapy. Fever and lymphadenopathy persisted. Peripheral lymph nodes tested positive for Bartonella henselae DNA in real‐time PCR assay and sequencing. Treatment with pradofloxacin and doxycycline resulted in resolution of clinical signs, and negative PCR tests. Despite its reported low pathogenicity, B. henselae infection should also be considered in cats with protracted unexplained fever, lymphadenitis, and IMHA. Furthermore, a combination of pradofloxacin and doxycycline might be considered in cats with bartonellosis given its apparent clinical efficacy.

Associations between presence of Bartonella species deoxyribonucleic acid and complete blood cell count and serum biochemical changes in client-owned cats

Background

Infection with Bartonella species is common in cats but reported effects of bacteremia on laboratory variables differ.

Objectives

Evaluate for associations between Bartonella bacteremia and CBC and serum biochemical changes in sick and healthy cats throughout the United States.

Animals

A total of 3964 client‐owned cats.

Methods

Retrospective cohort study using submissions to a commercial laboratory between 2011 and 2017. Serum biochemistry and CBC abnormalities (categorized as above or below reference intervals), age, and location (high‐ or low‐risk state for Ctenocephalides felis) in presumed healthy and sick cats were evaluated for associations with presence of Bartonella spp. DNA, detected by PCR. Univariate and multivariable logistic regression analyses were performed.

Results

Bartonella spp. DNA was amplified from 127 (3.2%) of 3964 cats; 126 (99.2%) of 127 were from high flea risk states and 121 (95.3%) of 127 were presumed sick. Fever of unknown origin was the most common PCR panel requested. In the multivariable analysis, neutrophilia, decreased ALP activity, clinical status (presumed sick), and young age (≤2 years) each were positively associated whereas neutropenia and hyperproteinemia both were negatively associated with Bartonella spp. bacteremia. Presence of Bartonella spp. DNA had no association with test results for other infectious disease agents.

Conclusions and Clinical Importance

In both healthy and sick cats, active Bartonella infections had minimal association with clinically relevant laboratory abnormalities. However, based on these results, in areas considered high risk for C. felis, active infection with Bartonella spp. is a reasonable differential diagnosis for cats presented with unexplained fever and neutrophilia, particularly if the cat is young.

Prospective serological and molecular cross-sectional study focusing on Bartonella and other blood-borne organisms in cats from Catalonia (Spain)

Background

There is limited clinical or epidemiological knowledge regarding Bartonella infection in cats, and no serological studies have compared the presence of antibodies against different Bartonella species. Moreover, there are limited feline Bartonella studies investigating co-infections with other vector-borne pathogens and the associated risk factors. Therefore, the objective of this study was to investigate Bartonella spp. infections and co-infections with other pathogens in cats from Barcelona (Spain) based on serological and/or molecular techniques and to determine associated risk factors.

Methods

We studied colony and owned cats (n = 135). Sera were tested for Bartonella henselae-, Bartonella quintana-, and Bartonella koehlerae-specific antibodies using endpoint in-house immunofluorescence antibody assays. Bartonella real-time PCR (qPCR) and conventional PCR (cPCR) were performed. In addition, cPCR followed by DNA sequencing was performed for other pathogenic organisms (Anaplasma, Babesia, Cytauxzoon, Ehrlichia, Hepatozoon, hemotropic Mycoplasma, and Theileria spp.).

Results

From 135 cats studied, 80.7% were seroreactive against at least one Bartonella species. Bartonella quintana, B. koehlerae, and B. henselae seroreactivity was 67.4, 77.0, and 80.7%, respectively. Substantial to almost perfect serological agreement was found between the three Bartonella species. Colony cats were more likely to be Bartonella spp.-seroreactive than owned cats. Moreover, cats aged ≤ 2 years were more likely to be Bartonella spp.-seroreactive. Bartonella spp. DNA was detected in the blood of 11.9% (n = 16) of cats. Cats were infected with B. henselae (n = 12), B. clarridgeiae (n = 3), and B. koehlerae (n = 1). Mycoplasma spp. DNA was amplified from 14% (n = 19) of cat blood specimens. Cats were infected with Mycoplasma haemofelis (n = 8), Candidatus M. haemominutum (n = 6), Candidatus Mycoplasma turicensis (n = 4), and Mycoplasma wenyonii (n = 1). Anaplasma, Babesia, Cytauxzoon, Ehrlichia spp., Hepatozoon, and Theileria spp. DNA was not amplified from any blood sample. Of the 16 Bartonella spp.-infected cats based on PCR results, six (37%) were co-infected with Mycoplasma spp.

Conclusions

Bartonella spp. and hemoplasma infections are prevalent in cats from the Barcelona area, whereas infection with Anaplasma spp., Babesia, Cytauxzoon, Ehrlichia spp., Hepatozoon, and Theileria infections were not detected. Co-infection with hemotropic Mycoplasma appears to be common in Bartonella-infected cats. To our knowledge, this study is the first to document M. wenyonii is infection in cats.

Graphical Abstract

Molecular Detection of Bartonella spp. and Hematological Evaluation in Domestic Cats and Dogs from Bangkok, Thailand

(1) Background: Bartonella spp. are Gram-negative, facultative, intracellular bacteria transmitted by hematophagous insects. Several species cause zoonotic diseases such as cat-scratch disease. Bartonella henselae and Bartonella clarridgeiae are the main species found in Thailand, however, there have been few studies on Bartonella spp. In addition, the hematological evaluation of Bartonella-infected animals is limited in Thailand. The aims of this study were prevalence investigation and hematological evaluation of Bartonella-infected dogs and cats residing in Bangkok, Thailand. (2) Methods: In total, 295 dogs and 513 cats were molecularly evaluated to detect Bartonella spp. using PCR with primers targeting the partial gltA, rpoB, ftsZ, ribC, and groEL genes. In total, 651 domestic animals were evaluated for hematological parameters compared between Bartonella-positive and Bartonella-negative animals. (3) Results: Overall, the prevalence of Bartonella spp. was 1.61% which was found only in free-ranging cats (2.83%). Bartonella henselae and B. clarridgeiae were confirmed from a concatenated phylogenetic tree of partial gltA and ribC genes, with 100% bootstrapping replication. For other housekeeping gene sequences, mixed infection was expected from the amplicons of rpoB, ftsZ, and groEL. Importantly, the mean corpuscular volume (MCV) was significantly increased in Bartonella-positive cats. (4) Conclusions: We suggest that B. henselae and B. clarridgeiae are important species and are still circulating in domestic animals, especially cats. The evaluation of blood parameters, especially a raised MCV, should be of concern in Bartonella infection in asymptomatic cats. Additionally, the knowledge of how to prevent Bartonella-related diseases should be promoted with people in at-risk situations.

Validation of Bartonella henselae Western Immunoblotting for Serodiagnosis of Bartonelloses in Dogs

Bartonella spp. are etiological agents of life-threatening zoonotic diseases in dogs worldwide. Due to the poor sensitivity of immunofluorescent-antibody assays (IFAs), a reliable serodiagnostic test for canine bartonelloses is of clinical importance. The utility of Western blotting (WB) for the serodiagnosis of canine bartonelloses has not been critically investigated. The objective of this study was to characterize WB immunodominant proteins that could be used to confirm a serodiagnosis of bartonelloses. Using agar-grown Bartonella henselae San Antonio type 2 (SA2) whole-cell proteins, sera derived from four dog groups were tested by WB to assess immunodominant protein recognition patterns: group I consisted of 92 serum samples (10 preexposure and 82 postexposure serum samples) from 10 adult beagles experimentally inoculated with Bartonella spp., group II consisted of 36 serum samples from Bartonella PCR-positive naturally infected dogs, group III consisted of 26 serum samples from Bartonella PCR-negative and IFA-negative dogs, and group IV consisted of serum samples from 8 Brucella canis IFA-positive and 10 Rickettsia rickettsii IFA-positive dogs. Following experimental inoculation, 9 (90%) group I dogs were variably seroreactive to one or more of six specific immunodominant proteins (13, 17, 29, 50, 56, and 150 kDa). There was a strong but variable recognition of these proteins among 81% of group II dogs. In contrast, 24/26 group III dogs were not reactive to any immunodominant protein. In this study, the sensitivity and diagnostic accuracy of B. henselae SA2 WB were higher than those of B. henselae SA2 IFA testing. Some B. henselae SA2 immunodominant proteins were recognized by dogs experimentally and naturally infected with Bartonella spp. other than B. henselae Additional research is necessary to more fully define the utility of WB for the serodiagnosis of canine bartonelloses.

Molecular Survey of Bartonella Species in Shelter Cats in Rio De Janeiro: Clinical, Hematological, and Risk Factors

The present study aimed to detect Bartonella DNA in cats belonging to shelters, and to evaluate risk factors, clinical signs, and hematological abnormalities associated with infection. Complete blood counts and screening for the presence of Bartonella DNA were performed on cats' ethylenediamine tetraacetic acid anticoagulant-blood samples. Eighty-three cats (39.9%) were positive for Bartonella species. Bartonella DNA was also detected in fleas and in the blood of cats infested by positive flea. Cats that had not been sterilized, had outdoor access, had histories of fights, and had concurrent flea infestation were more likely to be infected by Bartonella species (P < 0.05). Age and sex were not associated with infection. Fifty-one (38.6%) symptomatic cats were positive to Bartonella species (P > 0.05). Clinical conditions most commonly observed were signs of respiratory abnormality and Sporothrix species coinfection (P > 0.05). Regarding hematological changes, eosinophilia was associated with infection (P < 0.05). A high frequency of Bartonella species infection was found in shelter cats and highlights the importance of adequate flea-control programs to prevent infection in cats and consequently in adopters and other animals.

Role of vector-borne pathogens in the development of fever in cats: 1. Flea-associated diseases

PRACTICAL RELEVANCE

There has been increasing identification of vector-borne pathogens in cats presented to veterinary clinics around the world for evaluation of fever and the associated secondary effects, such as signs of depression and loss of appetite.

AIM

The aim of this article is to summarize the clinically relevant information concerning fever in cats that is associated with pathogens known or suspected to be vectored by fleas, with an emphasis on presenting clinical abnormalities and optimal diagnostic, treatment and prevention strategies. Fever in cats that is associated with pathogens vectored by ticks or sandflies is discussed in Part 2 of this article series.

Feline Vector-Borne Diseases in North America

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

Prevalence of Selected Zoonotic and Vector-Borne Agents in Dogs and Cats on the Pine Ridge Reservation

The prevalence of intestinal parasites and vector-borne agents of dogs and cats in the Pine Ridge Reservation, South Dakota were determined. Fecal samples (84 dogs, 9 cats) were examined by centrifugal floatation and by immunofluorescence assay (FA) for Giardia and Cryptosporidium. PCR was performed on Giardia [beta-giardin (bg), triose phosphate isomerase (tpi), glutamate dehydrogenase genes (gdh)] and Cryptosporidium [heat shock protein-70 gene (hsp)] FA positive samples. Cat sera (n = 32) were tested for antibodies against Bartonella spp., Toxoplasma gondii, and FIV, and antigens of FeLV and Dirofilaria immitis. Dog sera (n = 82) were tested for antibodies against T. gondii, Borrelia burgdorferi, Ehrlichia canis, and Anaplasma phagocytophilum and D. immitis antigen. Blood samples (92 dogs, 39 cats) were assessed by PCR for amplification of DNA of Bartonella spp., Ehrlichia spp., Anaplasma spp., haemoplasmas, and Babesia spp. (dogs only). The most significant results were Giardia spp. (32% by FA), Taenia spp. (17.8%) and Cryptosporidium spp. (7.1%). The Giardia isolates typed as the dog-specific assemblages C or D and four Cryptosporidium isolates typed as C. canis. Antibodies against T. gondii were detected in 15% of the dogs. Antibodies against Bartonella spp. and against T. gondii were detected in 37.5% and 6% of the cats respectively. FeLV antigen was detected in 10% of the cats.

Prevalence of selected infectious disease agents in stray cats in Catalonia, Spain

Objectives

The objective of the current study was to investigate the prevalence rates of the following infectious agents in 116 stray cats in the Barcelona area of Spain: Anaplasma phagocytophilum, Bartonella species, Borrelia burgdorferi, Chlamydia felis, Dirofilaria immitis, Ehrlichia species, feline calicivirus (FCV), feline herpesvirus-1 (FHV-1), feline leukaemia virus (FeLV), feline immunodeficiency virus (FIV), haemoplasmas, Mycoplasma species and Rickettsia species.

Methods

Serum antibodies were used to estimate the prevalence of exposure to A phagocytophilum, Bartonella species, B burgdorferi, Ehrlichia species and FIV; serum antigens were used to assess for infection by D immitis and FeLV; and molecular assays were used to amplify nucleic acids of Anaplasma species, Bartonella species, C felis, D immitis, Ehrlichia species, FCV, FHV-1, haemoplasmas, Mycoplasma species and Rickettsia species from blood and nasal or oral swabs.

Results

Of the 116 cats, 63 (54.3%) had evidence of infection by Bartonella species, FeLV, FIV or a haemoplasma. Anaplasma species, Ehrlichia species or Rickettsia species DNA was not amplified from these cats. A total of 18/116 cats (15.5%) were positive for FCV RNA (six cats), Mycoplasma species DNA (six cats), FHV-1 DNA (three cats) or C felis DNA (three cats).

Conclusions and relevance

This study documents that shelter cats in Catalonia are exposed to many infectious agents with clinical and zoonotic significance, and that flea control is indicated for cats in the region.

Bartonella henselae as a cause of acute-onset febrile illness in cats

Case series summary

At different time points spanning 6 months, three adopted feral flea-infested cats, residing in the household of a veterinary technician, became acutely anorexic, lethargic and febrile. Enrichment blood culture/PCR using Bartonella alpha Proteobacteria growth medium (BAPGM) confirmed initial infection with the same Bartonella henselae genotype in all three cases. With the exception of anemia and neutropenia, complete blood counts, serum biochemical profiles and urinalysis results were within reference intervals. Also, tests for feline leukemia virus, feline immunodeficiency virus, Toxoplasma gondii and feline coronavirus antibodies were negative. Serial daily temperature monitoring in one case confirmed a cyclic, relapsing febrile temperature pattern during 1 month, with resolution during and after treatment with azithromycin. Bartonella henselae Western immunoblot (WB) results did not consistently correlate with BAPGM enrichment blood culture/PCR results or B henselae indirect fluorescent antibody (IFA) titers, and WB titration results were not informative for establishing antibiotic treatment failure. During the respective follow-up periods, no illnesses or additional febrile episodes were reported, despite repeat documentation of B henselae bacteremia in two cats available for follow-up (one with the same genotype and the other with a different B henselae genotype); one cat was, unfortunately, killed by dogs before follow-up testing.

Relevance and novel information

We conclude that microbiological diagnosis and treatment of B henselae infection in cats can be challenging, that antibody titration results and resolution of clinical abnormalities may not correlate with a therapeutic cure, and that fever and potentially neutropenia should be differential diagnostic considerations for young cats with suspected bartonellosis.

Felis catus gammaherpesvirus 1; a widely endemic potential pathogen of domestic cats

Felis catus gammaherpesvirus 1 (FcaGHV1), recently discovered in the USA, was detected in domestic cats in Australia (11.4%, 95% confidence interval 5.9-19.1, n=110) and Singapore (9.6%, 95% confidence interval 5.9-14.6, n=176) using qPCR. FcaGHV1 qPCR positive cats were 2.8 times more likely to be sick than healthy. Risk factors for FcaGHV1 detection included being male, increasing age and coinfection with pathogenic retroviruses, feline immunodeficiency virus (FIV) or feline leukaemia virus. FcaGHV1 DNA was detected in multiple tissues from infected cats with consistently high virus loads in the small intestine. FcaGHV1 viral load was significantly higher in FIV-infected cats compared with matched controls, mimicking increased Epstein-Barr virus loads in human immunodeficiency virus-infected humans. FcaGHV1 is endemic in distant geographic regions and is associated with being sick and with coinfections. Horizontal transmission of FcaGHV1 is supported, with biting being a plausible route. A pathogenic role for FcaGHV1 in domestic cats is supported.

Bartonella species infection in cats: ABCD guidelines on prevention and management

OVERVIEW

Over 22 Bartonella species have been described in mammals, and Bartonella henselae is most common worldwide. Cats are the main reservoir for this bacterium. B henselae is the causative agent of cat scratch disease in man, a self-limiting regional lymphadenopathy, but also of other potentially fatal disorders in immunocompromised people.

INFECTION

B henselae is naturally transmitted among cats by the flea Ctenocephalides felis felis, or by flea faeces. A cat scratch is the common mode of transmission of the organism to other animals, including humans. Blood transfusion also represents a risk.

DISEASE SIGNS

Most cats naturally infected by B henselae do not show clinical signs but cardiac (endocarditis, myocarditis) or ocular (uveitis) signs may be found in sporadic cases. B vinsonii subspecies berkhoffii infection has reportedly caused lameness in a cat affected by recurrent osteomyelitis and polyarthritis.

DIAGNOSIS

Isolation of the bacterium is the gold standard, but because of the high prevalence of infection in healthy cats in endemic areas, a positive culture (or polymerase chain reaction) is not confirmatory. Other compatible diagnoses must be ruled out and response to therapy gives a definitive diagnosis. Serology (IFAT or ELISA) is more useful for exclusion of the infection because of the low positive predictive value (39-46%) compared with the good negative predictive value (87-97%). Laboratory testing is required for blood donors.

DISEASE MANAGEMENT

Treatment is recommended in the rare cases where Bartonella actually causes disease.

A flea and tick collar containing 10% imidacloprid and 4.5% flumethrin prevents flea transmission of Bartonella henselae in cats

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.

Prevalence of Toxoplasma gondii, Bartonella species and haemoplasma infection in cats in South Africa

Vector-borne agents and Toxoplasma gondii are common in cats, with many being zoonotic. The current study investigated the prevalence of selected infectious agents in cats from Johannesburg, South Africa, for which no published data exists. Whole blood and sera were obtained from 102 cats with a variety of disease conditions. Total DNA was extracted from the blood and assayed using PCR techniques for Mycoplasma haemofelis, Candidatus M haemominutum, Candidatus M turicensis, Bartonella species, Ehrlichia species and Anaplasma species. Enzyme-linked immunosorbent assays were used to detect IgG and IgM serum antibodies to T gondii and IgG serum antibodies to Bartonella species. Associations between test results, patient characteristics and haematological values were also evaluated. Overall, 56 cats (55%) were positive in one or more of the assays. Haemoplasma DNA was amplified from 26 cats [M haemofelis: four cats (3.9%); Candidatus M haemominutum from 22 cats (21.6%)] and Bartonella species DNA was amplified from eight cats [Bartonella henselae: five cats (4.9%); Bartonella clarridgeieae: three cats (2.9%)]; DNA of Ehrlichia species or Anaplasma species were not amplified. Of the cats, 24 (23.5%) were seropositive for Bartonella IgG and 18 (17.6%) were positive for T gondii IgM (12 cats), IgG (eight cats), or both (two cats). The study concluded that Bartonella species haemoplasmas and T gondii are common in client-owned cats in the region and the diagnosis of feline vector-borne agents and T gondii is difficult without the use of specific diagnostic tests, as there are minimal patient characteristics or haematological changes that indicate infection.

An investigation into the seroprevalence of Toxoplasma gondii, Bartonella spp., feline immunodeficiency virus (FIV), and feline leukaemia virus (FeLV) in cats in Addis Ababa, Ethiopia

Toxoplasma gondii and Bartonella spp. are zoonotic pathogens of cats. Feline immunodeficiency virus (FIV), and feline leukaemia virus (FeLV) are immunosuppressive viruses of cats that can affect T. gondii oocyst shedding. In this study, the prevalence of antibodies to T. gondii, Bartonella spp., FIV, as well as FeLV antigens were determined in sera from feral cats (Felis catus) from Addis Ababa, Ethiopia. Using the modified agglutination test, IgG antibodies to T. gondii were found in 41 (85·4%) of the 48 cats with titres of 1:25 in one, 1:50 in one, 1:200 in six, 1:400 in six, 1:800 in six, 1:1600 in eight, and 1:3200 in 13 cats. Toxoplasma gondii IgM antibodies were found in 11/46 cats tested by ELISA, suggesting recent infection. Antibodies to Bartonella spp. were found in five (11%) of 46 cats tested. Antibodies to FIV or FeLV antigen were not detected in any of the 41 cats tested. The results indicate a high prevalence of T. gondii and a low prevalence of Bartonella spp. infection in cats in Ethiopia.

Prevalence of Bartonella species, hemoplasmas, and Rickettsia felis DNA in blood and fleas of cats in Bangkok, Thailand

Flea infestations are common in Thailand, but little is known about the flea-borne infections. Fifty flea pools and 153 blood samples were collected from client-owned cats between June and August 2009 from veterinary hospitals in Bangkok, Thailand. Total DNA was extracted from all samples, and then assessed by conventional PCR assays. The prevalence rates of Bartonella spp. in blood and flea samples were 17% and 32%, respectively, with DNA of Bartonella henselae and Bartonella clarridgeiae being amplified most commonly. Bartonella koehlerae DNA was amplified for the first time in Thailand. Hemoplasma DNA was amplified from 23% and 34% of blood samples and flea pools, respectively, with 'Candidatus Mycoplasma haemominutum' and Mycoplasma haemofelis being detected most frequently. All samples were negative for Rickettsia felis. Prevalence rate of B. henselae DNA was increased 6.9 times in cats with flea infestation. Cats administered flea control products were 4.2 times less likely to be Bartonella-infected.

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.

Detection of Bartonella henselae IgM in serum of experimentally infected and naturally exposed cats

BACKGROUND

Results of Bartonella henselae blood culture, polymerase chain reaction (PCR) assay on blood, or IgG antibody assays do not always correlate with the presence or absence of clinical disease in cats, and B. henselae IgG antibodies in serum do not always correlate with bacteremia. However, little is known concerning Bartonella spp. IgM antibodies in naturally exposed cats.

HYPOTHESIS

Bartonella spp. IgM antibodies in serum are associated with fever, stomatitis, and bacteremia based on PCR assay results in experimentally infected or client-owned cats.

ANIMALS

Stored sera from cats experimentally infected with B. henselae by exposure to Ctenocephalides felis, client-owned cats with and without fever, and client-owned cats with and without stomatitis were studied.

METHODS

A Bartonella spp. IgM ELISA was titrated with samples from experimentally infected cats and then test sera from client-owned cats were assayed. Associations among IgM ELISA results, clinical findings, and bacteremia as defined by Bartonella spp. PCR assay were assessed.

RESULTS

All experimentally infected cats developed Bartonella spp. IgM antibodies. Bartonella spp. IgM antibody assay results were not always in agreement with PCR assay results in client-owned cats (60%). Bartonella spp. DNA in blood, IgM antibodies, and IgG antibodies were not associated with the presence of fever or stomatitis.

CONCLUSIONS AND CLINICAL IMPORTANCE

Because Bartonella spp. IgM antibodies as measured by this assay were not associated with fever or stomatitis and were not always in agreement with PCR assay results, there appears to be little need for assessing individual client-owned cats for this antibody class alone.

Prevalence of Bartonella species, haemoplasmas and Toxoplasma gondii in cats in Scotland

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.

Feline bartonellosis

Bartonella infection is common among domestic cats, but the role of Bartonella species as feline pathogens requires further study. Most Bartonella species that infect cats are zoonotic. Cats are the mammalian reservoir and vector for Bartonella henselae, an important zoonotic agent. Cat fleas transmit Bartonella among cats, and cats with fleas are an important source of human B henselae infections. New information about Bartonella as feline pathogens has recently been published, and this article summarizes much of that information. Issues surrounding diagnosis and treatment of feline Bartonella infections are described, and prevention of zoonotic transmission of Bartonella is discussed.

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

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.

Association between Bartonella species infection and disease in pet cats as determined using serology and culture

This study's objective was to determine whether a relationship exists between infection or seropositivity to Bartonella species and clinical illness in cats. Blood samples were obtained for Bartonella species isolation and immunofluorescent antibody serology from 298 cats presenting to a tertiary referral hospital. Medical records were searched and the history, physical examination findings and the results of diagnostic testing relating to the visit at which Bartonella species testing was performed were recorded. Fifty-two (17%) samples were seropositive for Bartonella henselae, four (1%) for Bartonella clarridgeiae, and 57 (19%) for both organisms. Nineteen (6.4%) samples were culture positive, 17 for B henselae and two for B clarridgeiae. Gingivostomatitis was associated with Bartonella species isolation (P=0.001), but not seropositivity. There was no association with uveitis, neurologic signs, or chronic kidney disease, and a weak association between seropositivity and idiopathic lower urinary tract disease (feline interstitial cystitis) (P=0.05).

Prevalence of selected infectious agents in cats in Ireland

Vector-borne bacterial and rickettsial agents and Toxoplasma gondii, are common organisms in cats. Some are potentially zoonotic or may be transmitted via blood transfusion. The current study investigated the prevalence of these agents in cats from Dublin, Ireland, for which no published data exists. Whole blood (n=116) and sera (n=83) samples were obtained from 121 cats. DNA was extracted from blood and assayed using polymerase chain reaction techniques for Anaplasma species, Bartonella species, Ehrlichia species, Mycoplasma haemofelis, 'Candidatus Mycoplasma haemominutum', 'Candidatus Mycoplasma turicensis' and Rickettsia species. IgG and T gondii IgG and IgM serum antibodies were detected by enzyme-linked immunosorbent assay. DNA consistent with B henselae (3.4%), B clarridgeiae (0.8%), both Bartonella species (0.8%), C M haemominutum (12.9%), or M haemofelis (2.5%) was amplified from 24/116 blood samples (20.6%). Antibodies to T gondii and Bartonella species were detected in 28 (33.7%) and 22 (26.5%) of 83 sera, respectively.

Association of Bartonella species, feline calicivirus, and feline herpesvirus 1 infection with gingivostomatitis in cats

Feline gingivostomatitis (FGS) is a common syndrome in cats; feline calicivirus (FCV), feline herpesvirus 1 (FHV-1), and Bartonella species are common differential diagnoses. In this study, blood from 70 cats with FGS and 61 healthy control cats was tested for Bartonella species antibodies in serum by enzyme-linked immunosorbent assay and Western blot immunoassay and DNA in blood using a conventional polymerase chain reaction assay. Additionally, fresh oral biopsies from cats with FGS (n=42) and 19 healthy controls were tested for FCV RNA, FHV-1 DNA and Bartonella species DNA. The prevalence rates for Bartonella species antibodies and DNA in the blood and the tissues did not differ between the two groups. FHV-1 DNA was also not significantly different between groups. Only FCV RNA was present in significantly more cats with FGS (40.5%) than control cats (0%). The results suggest that FCV was associated with FGS in some of the cats.

Seroprevalence of Toxoplasma gondii and Bartonella spp. antibodies in cats from Pennsylvania

Toxoplasma gondii and Bartonella spp. are zoonotic pathogens of cats. In the present study, the prevalence of antibodies to T. gondii and Bartonella spp. were determined in sera from 210 domestic cats from Bensalem, Pennsylvania. Using a modified agglutination test, antibodies to T. gondii were found in 41 (19.5%) of the 210 cats with titers of 1:25 in 4, 1:50 in 9, 1:100 in 7, 1:200 in 3, 1:400 in 3, 1:800 in 5, 1:1,600 in 4, and 1:3,200 or higher in 6. For T. gondii, seroprevalence increased with age of the cat: 15 of 113 (13.2 %) were seropositive compared with 26 of 97 (26.7%) older than 11 mo. Of these 210 cats, 54 (25.7%) were positive for Bartonella spp. antibodies, with titers of 1:64 in 20, 1:128 in 21, 1:256 in 9, and 1:512 in 4. Seventeen cats had antibodies to both organisms. There was no correlation between T. gondii and Bartonella spp. seropositivity. Overall the seroprevalence of T. gondii antibodies in cats in this population is much lower compared with those reported in other localities in the United States and other countries.

Infectious disease diagnostic assays

Dogs and cats are commonly exposed to infectious disease agents. The following article is an update on the most common infectious disease assays used in small animal practice. In some situations, results of pathogen-specific molecular diagnostic assays can be used to assist the practicing veterinarian in the management of patients with infectious diseases. However, with some infectious disease agents, the assays are positive in healthy and ill animals and can be falsely negative and so the predictive values of the assays vary.

Prevalence of Rickettsia species antibodies and Rickettsia species DNA in the blood of cats with and without fever

Rickettsia species antibodies have been detected in some cats but it is unknown whether infected cats develop clinical signs. The prevalence of Rickettsia species deoxyribonucleic acid (DNA) in blood from clinically ill cats has not been determined. The objective of this study was to determine if cats with fever (body temperature >or=102.5 degrees F [39.2 degrees C]) were more likely to have evidence of rickettsial infection than healthy, age-matched, control cats with a body temperature<102.5 degrees F. Rickettsia species polymerase chain reaction (PCR) assays were performed to detect rickettsial DNA extracted from blood (71 paired samples), indirect immunofluorescence assays (IFA) were performed to detect serum antibodies against Rickettsia felis (90 paired samples) and Rickettsia rickettsii (91 paired samples), and the results between pairs were compared. All samples were negative for Rickettsia species DNA. More cats with fever were seropositive for R felis or R rickettsii than control cats, but results were not statistically significant. Results of this pilot study failed to show an association between Rickettsia species DNA or Rickettsia species antibodies and fever.