Effect of chronic FIV infection, and efficacy of marbofloxacin treatment, on Mycoplasma haemofelis infection

The purpose of this study was to investigate the effect of chronic feline immunodeficiency virus (FIV) infection, and efficacy of marbofloxacin treatment, on Mycoplasma haemofelis infection. Six cats chronically infected with FIV-Glasgow8 (Group X) and six FIV-free cats (Group Y) were infected with M. haemofelis on Day 0 by intravenous blood inoculation. From Day 0 until Day 86 post-infection (pi), blood samples were collected for M. haemofelis and FIV provirus quantitative real-time PCR and haematology. Three of the six cats in each of Groups X and Y were randomly selected to receive marbofloxacin treatment (2 mg/kg PO q24 h) from Day 16 to 43 pi, with the remaining cats being untreated controls with no antibiotic treatment. The M. haemofelis copy numbers and haematological data were compared between Groups X and Y, and between marbofloxacin-treated and control cats using a Mann-Whitney U-test. M. haemofelis infection was associated with development of macrocytic hypochromic anaemia. In some cats, marked variation in M. haemofelis copy number over time (>100,000-fold difference within 48 h in some cats) and/or cycling of copy number was seen. No correlation was found between FIV provirus copy number and M. haemofelis copy number or haematological variables. No significant effect of chronic FIV infection on M. haemofelis copy number kinetics or haematological changes due to M. haemofelis infection was found, other than MCHC (P=0.03). Marbofloxacin treatment was associated with a significant decrease in M. haemofelis copy number (P=0.002), although consistent clearance of infection was not demonstrated. This study reveals the presence of marked fluctuations in M. haemofelis copy number kinetics in vivo and a significant response to marbofloxacin antibiotic treatment.     

Prevalence of feline immunodeficiency virus infection in domesticated and feral cats in eastern Australia

Serum samples from 340 pet cats presented to three inner city clinics in Sydney Australia, 68 feral cats from two separate colonies in Sydney, and 329 cattery-confined pedigree and domestic cats in eastern Australia, were collected over a 2-year period and tested for antibodies directed against feline immunodeficiency virus (FIV) using immunomigration (Agen FIV Rapid Immunomigration test) and enzyme-linked immunosorbent assay methods (Snap Combo feline leukaemia virus antigen/FIV antibody test kit, IDEXX Laboratories). Western blot analysis was performed on samples in which there was discrepancy between the results. Information regarding breed, age, gender, housing arrangement and health status were recorded for all pet and cattery-confined cats, while the estimated age and current physical condition were recorded for feral cats. The FIV prevalence in the two feral cat populations was 21% and 25%. The majority of FIV-positive cats were male (60-80%). The FIV prevalence in cattery-confined cats was nil. The prevalence of FIV in the pet cat sample population was 8% (27/340) with almost equal prevalence in 'healthy' (13/170) and 'systemically unwell' (14/170) cats. The age of FIV-positive pet cats ranged from 3 to 19 years; all FIV-positive cats were domestic shorthairs with outside access. The median age of FIV-positive pet cats (11 years) was significantly greater than the median age of FIV-negative pet cats (7.5 years: P<0.05). The prevalence of FIV infection in male pet cats (21/172; 12%) was three times that in female pet cats (6/168; 4%; P<0.05). With over 80% of this pet cat population given outside access and continued FIV infection present in the feral population, this study highlights the need to develop rapid, accurate and cost-effective diagnostic methods that are not subject to false positives created by concurrent vaccination against FIV. This is especially important in re-homing stray cats within animal shelters and monitoring the efficacy of the new vaccine, which has not been challenged against Australian strains. The absence of FIV within cattery-confined cats highlights the value in routine screening and indoor lifestyles. This study provides cogent baseline FIV prevalences in three cat subpopulations which can be used for appraising potential disease associations with FIV in Australia.     

Prevalence of selected infectious disease agents in cats from Arizona

The objective of this study was to use polymerase chain reaction (PCR) assays to determine the prevalence of Ehrlichia species, Anaplasma phagocytophilum, Mycoplasma haemofelis, 'Candidatus Mycoplasma haemominutum' and Bartonella species from feral and relinquished cats in Phoenix and Nogales, Arizona. DNA from one or more of the organisms was amplified from 31 of 112 blood samples (27.7%). DNA consistent with Bartonella clarridgeiae 15 (13.4%), Bartonella henselae 14 (12.5%), 'Candidatus M haemominutum' 9 (8.0%), and M haemofelis 5 (4.5%) were detected. DNA of Ehrlichia species, Neorickettsia risticii, or A phagocytophilum was not amplified. Failure to amplify DNA of A phagocytophilum may relate to the absence of appropriate tick vectors. Failure to amplify Ehrlichia species DNA suggests that cats were not exposed, exposed but not infected, or infected but the DNA was not detected by the PCR assay used in this study. The Bartonella species and hemoplasma results suggest flea control should be maintained.     

Prevalence and risk factors for hemoplasmas in domestic cats naturally infected with feline immunodeficiency virus and/or feline leukemia virus in Rio de Janeiro--Brazil

The aim of this study was to determine the prevalence and risk factors for Mycoplasma haemofelis (Mhf) and 'Candidatus Mycoplasma haemominutum' (Mhm) infections in domestic cats tested for feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) with a commercial enzyme-linked immunosorbent assay (ELISA) kit. Based on serological testing, cats were grouped as i) FIV-positive (n=25); ii) FeLV-positive (n=39); iii) FIV/FeLV-positive (n=8); and iv) FIV/FeLV-negative (n=77). Complete blood counts were followed by DNA extraction, species-specific polymerase chain reaction (16S rRNA gene) for Mhf and Mhm and Southern blotting for all animals. Mhf DNA was found in 4.0, 2.6, 12.5 and 7.8% of the cats from groups i, ii, iii and iv, respectively, while 32, 5.1, 50 and 5.2% of these animals had an Mhm infection. Cats with FIV (OR=4.25, P=0.009) and both FIV and FeLV (OR=7.56, P=0.014) were at greater risk of being hemoplasma infected than retroviral-negative cats, mainly due to Mhm infection (OR=8.59, P=0.001 and OR=18.25, P=0.001, respectively). Among pure-breed cats, FIV-positive status was associated with hemoplasma infection (OR 45.0, P=0.001).     

Molecular detection of feline hemoplasmas in feral cats in Korea

The purpose of this study was to determine if Mycoplasma haemofelis, 'Candidatus Mycoplasma haemominutum' exist in Korea. Three hundreds and thirty one feral cats were evaluated by using PCR assay targeting 16S rRNA gene sequence. Fourteen cats (4.2%) were positive for M. haemofelis, 34 cats (10.3%) were positive for 'Candidatus M. haemominutum' and 18 cats (5.4%) were positive for both species. Partial 16S rRNA gene sequences were closely (>98%) related to those from other countries. This is the first molecular detection of feline hemoplasmas in Korea.     

Seroprevalence of feline immunodeficiency virus, feline leukaemia virus and Toxoplasma gondii in stray cat colonies in northern Italy and correlation with clinical and laboratory data

Stray cat colonies in urban and rural areas of Lombardy, northern Italy, were surveyed for seroprevalence of feline immunodeficiency virus (FIV) antibodies, feline leukaemia virus (FeLV) antigen and Toxoplasma gondii IgG. Of 316 cats tested, 6.6% were positive for FIV and 3.8% were positive for FeLV infection; 203 cats were tested for T gondii IgG antibodies and a prevalence of 30.5% was detected. Statistical analysis tested the influence of provenience, age, gender, health status and laboratory results on seroprevalence and found male gender and adult age were risk factors for FIV infection. FIV-infected cats were more likely to have a decreased red blood cell count than FIV seronegative cats. No predictors were significantly associated with FeLV and T gondii seropositivity. Colony cats in this study posed a limited risk for retrovirus infection to pet cats allowed outdoors, whereas toxoplasmosis exposure was comparable with the worldwide data.     

A comparison of serum vitamin A and vitamin E concentrations in shelter, feral, and pet cats

Upper respiratory infection (URI) is an important cause of morbidity and mortality in shelter cats. Malnutrition, specifically vitamin A deficiency, has been associated with respiratory tract infections in humans in developing countries. The purpose of this study was to determine whether feral cats and cats in shelters have lower serum vitamin A concentrations than pet cats, because it was surmised that a vitamin A deficiency may predispose these cats to develop URI. This was a cross-sectional study in which serum retinol, α-tocopherol, γ-tocopherol and beta carotene concentrations were measured from 48 shelter cats, 56 feral cats, and 42 pet cats, using HPLC. Retinol, α-tocopherol, and γ-tocopherol concentrations were found to be significantly lower in the shelter and feral cat populations than in pet cats (p ≤ 0.0001). There was no evidence of an effect of sex or neuter status on vitamin concentrations. Sick feral cats had a higher beta carotene level than did healthy feral cats. Within shelter and feral populations, no other effect of health status was found. The lower mean serum retinol and tocopherol concentrations in the feral and shelter cat groups could be due to oxidative or other forms of stress, the amount of vitamin consumed, or combinations of these. Further studies are needed to determine whether supplementation of fat-soluble vitamins improves the health status of feral or shelter cats.     

Prevalence of feline haemotropic mycoplasmas in convenience samples of cats in Germany

The aim of this prospective study was to evaluate the prevalence of feline haemotropic mycoplasmas in Germany, to determine probable risk factors for these infections and to compare the diagnostic value of microscopic examination of blood smears to polymerase chain reaction (PCR). For the prevalence study, convenience samples (Ethylene diamine-tetraacetic acid (EDTA) blood) from 262 (64.5% male and 35.5% female) cats were included. A PCR for the detection of Mycoplasma haemofelis (MHF) and 'Candidatus Mycoplasma haemominutum' (CMH) as well as a feline leukaemia virus (FeLV)/feline immunodeficiency virus (FIV) enzyme-linked immunoassay was performed. Blood smears from 224 cats were examined and the sensitivity and specificity of the microscopic diagnosis were determined. The prevalence of CMH, MHF, and CMH/MHF co-infection was 22.5%, 4.5%, and 0.8%, respectively. CMH was significantly associated with male gender (P=0.047), older age (P=0.0015) and both FeLV (P=0.002) and FIV infections (P<0.0001). However, there was no association between the presence of anaemia and CMH/MHF infection. The respective sensitivity and specificity of the microscopic diagnosis were 10.3% and 87.1% for a CMH infection and 0.0% and 98.0% for MHF infection.     

Seroprevalences of antibodies against Bartonella henselae and Toxoplasma gondii and fecal shedding of Cryptosporidium spp, Giardia spp, and Toxocara cati in feral and pet domestic cats

OBJECTIVE: To compare seroprevalences of antibodies against Bartonella henselae and Toxoplasma gondii and fecal shedding of Cryptosporidium spp, Giardia spp, and Toxocara cati in feral and pet domestic cats. DESIGN: Prospective cross-sectional serologic and coprologic survey. ANIMALS: 100 feral cats and 76 pet domestic cats from Randolph County, NC. PROCEDURE: Blood and fecal samples were collected and tested. RESULTS: Percentages of feral cats seropositive for antibodies against B. henselae and T. gondii (93% and 63%, respectively) were significantly higher than percentages of pet cats (75% and 34%). Percentages of feral and pet cats with Cryptosporidium spp (7% of feral cats; 6% of pet cats), Giardia spp (6% of feral cats; 5% of pet cats), and T. cati ova (21% of feral cats; 18% of pet cats) in their feces were not significantly different between populations. Results of CBCs and serum biochemical analyses were not significantly different between feral and pet cats, except that feral cats had a significantly lower median PCV and significantly higher median neutrophil count. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that feral and pet cats had similar baseline health status, as reflected by results of hematologic and serum biochemical testing and similar prevalences of infection with Cryptosporidium spp, Giardia spp, and T. cati. Feral cats did have higher seroprevalences of antibodies against B. henselae and T. gondii than did pet cats, but this likely was related to greater exposure to vectors of these organisms.     

Molecular survey of Mycoplasma haemofelis and 'Candidatus mycoplasma haemominutum' infection in cats in Yamaguchi and surrounding areas

A molecular survey of hemoplasma (Mycoplasma haemofelis and 'Candidatus Mycoplasma haemominutum') in Yamaguchi Prefecture and surrounding areas was performed by using molecular methods. PCR-RFLP with HindIII revealed that 2 cats were infected with M. haemofelis, and 16 with 'C. Mycoplasma haemominutum' among 102 randomly selected cats. Partial 16S rRNA gene sequences of M. haemofelis and 'C. Mycoplasma haemominutum' determined in this study showed percent similarities of 98.3-99.8% and 96.4-100%, respectively, with those from other countries. Hemoplasma infections were more frequently detected in free-roaming cats than inside cats. Also, the status of FeLV infection was another significant risk factor for hemoplasma infection.     

Mycoplasma haemofelis and Mycoplasma haemominutum detection by polymerase chain reaction in cats from Saskatchewan and Alberta

Hemobartonellosis is caused by Mycoplasma haemofelis, previously known as Haemobartonella felis. Cats infected with this organism typically develop regenerative anemia. The related species Mycoplasma haemominutum may also cause anemia. The purposes of this study were to use polymerase chain reaction technology to determine if both organisms exist in naturally infected cats from Saskatchewan and Alberta, and to determine if disease manifestation corresponds to mycoplasma species. Thirteen of 18 cats with regenerative anemia were infected, 12 with M. haemofelis and 1 with M. haemominutum. Eight of 22 cats with nonregenerative anemia were infected, 4 with M. haemofelis and 4 with M. haemominutum. Two of 20 cats with normal complete blood (cell) counts were infected with M. haemominutum. Although both mycoplasma species were identified, ill cats were more often infected with M. haemofelis.     

Acute phase response to Mycoplasma haemofelis and 'Candidatus Mycoplasma haemominutum' infection in FIV-infected and non-FIV-infected cats

The pathogenicity of Haemoplasma spp. in cats varies with 'Candidatus Mycoplasma haemominutum' (CMhm) causing subclinical infection while Mycoplasma haemofelis (Mhf) often induces haemolytic anaemia. The aims of this study were to characterise the acute phase response (APR) of the cat to experimental infection with Mhf or CMhm, and to determine whether chronic feline immunodeficiency virus (FIV) infection influences this response. The acute phase proteins serum amyloid A (SAA), haptoglobin (Hp) and α-1-acid glycoprotein (AGP) concentrations were measured pre-infection and every 7-14days up to day 100 post-infection (pi) in cats infected with either Mhf or CMhm. Half of each group of cats (6/12) were chronically and subclinically infected with FIV. Marbofloxacin treatment was given on days 16-44 pi to half of the Mhf-infected cats, and on days 49-77 pi to half of the CMhm-infected cats. FIV-infected animals had significantly lower AGP concentrations, and significantly greater Hp concentrations than non-FIV-infected cats when infected with CMhm and Mhf, respectively. Both CMhm and Mhf infection were associated with significant increases in SAA concentrations, while AGP concentrations were only significantly increased by Mhf infection. Mhf-infected cats had significantly greater SAA concentrations than CMhm-infected animals. Both Mhf and CMhm infections were associated with an APR, with Mhf infection inducing a greater response. Chronic FIV infection appeared to modify the APR, which varied with the infecting Haemoplasma species.     

Co-infection with Mycoplasma haemofelis and 'Candidatus Mycoplasma haemominutum' in three cats from Brazil

The two most common haemotropic Mycoplasma of cats, Mycoplasma haemofelis and 'Candidatus Mycoplasma haemominutum' have been identified using molecular techniques in all continents, except Antarctica. We report the first molecular characterization in South America of a dual infection with M haemofelis and 'Candidatus Mycoplasma haemominutum' in three domestic cats. The 16S ribosomal RNA gene was amplified in three anaemic cats in which haemoplasma organisms were seen attached to the erythrocytes in the peripheral blood smear. Bands of the expected size for M haemofelis and 'Candidatus Mycoplasma haemominutum' were observed in all three cats. The 393 bp segment of one of the amplicons had a similarity value of 100% to M haemofelis, whereas the other amplicon, a 192 bp segment, was 100% similar to 'Candidatus Mycoplasma haemominutum'. After diagnosis, two cats received blood transfusion and they were all treated with doxycycline. All three cats recovered uneventfully.     

Infectious disease prevalence in a feral cat population on Prince Edward Island, Canada

Ninety-six feral cats from Prince Edward Island were used to determine the prevalence of selected infectious agents. The prevalence rates were 5.2% for feline immunodeficiency virus, 3.1% for feline leukemia virus, 3.1% for Mycoplasma haemofelis, 8.4% for Candidatus Mycoplasma haemominutum, 2.1% for Bartonella spp. and 29.8% for exposure to Toxoplasma gondii. Oocysts of T. gondii were detected in 1.3% of the fecal samples that were collected. Gender and retroviral status of the cats were significantly correlated with hemoplasma infections. Use of a flea comb showed that 9.6% of the cats had fleas; however, flea infestation was not associated with any of the infectious agents.     

High rate of feline immunodeficiency virus infection in cats in the Brazilian semiarid region: Occurrence,associated factors and coinfection with Toxoplasma gondii and feline leukemia virus

To evaluate the occurrence of feline immunodeficiency virus (FIV) and factors associated with this and to demonstrate occurrences of coinfection with Toxoplasma gondii and feline leukemia virus (FeLV) in cats, a total of 103 blood samples were collected from owned cats, during home visits. To diagnose FIV and FeLV, immunochromatographic kit was used and serological diagnoses of T. gondii, the indirect immunofluorescence test was performed. The occurrence of FIV-seropositive cats was 23.3% (24/103) and the factor associated with infection was male sex. T. gondii seropositivity of 53.4% (55/103) was observed and 75% of FIV cases (18/24) were positive for T. gondii coinfection. Only 0.9% (1/103) was positive for FeLV. It can be concluded that the seroprevalence of FIV in cats in the Brazilian semiarid region is high and that FIV positive cats were also likely to be T. gondii seropositive, while FeLV had very low occurrence in the study region.     

Prevalences of various hemoplasma species among cats in the United States with possible hemoplasmosis

OBJECTIVE: To determine prevalences of various hemoplasma species among cats in the United States with possible hemoplasmosis and identify risk factors for and clinicopathologic abnormalities associated with infection with each species. DESIGN: Cross-sectional study. Animals-310 cats with cytologic evidence of hemoplasmosis (n = 9) or acute or regenerative anemia (309). PROCEDURES: Blood samples were tested by means of a broad-spectrum conventional PCR assay for hemoplasma DNA and by means of 3 separate species-specific real-time PCR assays for DNA from "Candidatus Mycoplasma haemominutum" (Mhm), Mycoplasma haemofelis (Mhf), and "Candidatus Mycoplasma turicensis" (Mtc). RESULTS: Overall prevalences of Mhm, Mhf, and Mtc infection were 23.2% (72/310), 4.8% (15/310), and 6.5% (20/310), respectively. Mixed infections were detected in 20 (6.5%) cats. Cats infected with hemoplasmas were more likely to be male than were uninfected cats. Infection with FeLV or FIV was significantly associated with infection with Mhf. Compared with uninfected cats, cats infected with Mhf had higher reticulocyte counts, nucleated RBC counts, and mean corpuscular volume; cats infected with Mhm had higher mean corpuscular volume; and cats infected with Mtc had higher monocyte counts. CONCLUSIONS AND CLINICAL RELEVANCE: Results supported the suggestion that these 3 hemoplasma species commonly occur among cats in the United States and that pathogenicity of the 3 species varies.     

Prevalence and risk factors for heartworm infection in cats from northern Florida

Necropsies were performed on 630 adult cats in northern Florida to determine the prevalence and risk factors for heartworm infection in cats of this region. Heartworms were identified in 4.9% of cats, and serological evidence of heartworm exposure was present in 17% of cats. Not all cats from which heartworms were recovered were seropositive for heartworm antigen or antibody. There was no association between heartworm infection and co-infection with feline leukemia virus (FeLV) or feline immunodeficiency virus (FIV). Male cats were at higher risk of infection with heartworm, FeLV, or FIV than were females. Because even a single heartworm can cause clinical disease or death in cats, the authors conclude that cats in this region should receive heartworm prophylaxis to prevent heartworm infection.     

Prevalence of feline leukaemia virus and antibodies to feline immunodeficiency virus and feline coronavirus in stray cats sent to an RSPCA hospital

A total of 517 stray cats at an RSPCA veterinary hospital were tested for feline leukaemia virus (FeLV), feline coronavirus (FCoV) and feline immunodeficiency virus (FIV). The prevalence of FeLV was 3.5 per cent in all the cats, 1.4 per cent in healthy cats and 6.9 per cent in sick cats. FeLV positivity was associated only with disease of non-traumatic origin. Antibodies to FCoV were present in 22.4 per cent of the cats, and their prevalence was significantly higher in cats over two years old and in feral/semiferal cats. The prevalence of antibodies to FIV was 10.4 per cent in all the cats, 4.9 per cent in healthy cats and 16.7 per cent in sick cats. The prevalence of FIV antibodies was significantly higher in entire males and neutered males than in females, in cats over two years old compared with younger cats, and in cats suffering disease of non-traumatic origin rather than in healthy cats or cats suffering only from trauma. Sex, age and health status were each independently highly associated with FIV antibodies.     

Coinfection of Leishmania chagasi with Toxoplasma gondii, Feline Immunodeficiency Virus (FIV) and Feline Leukemia Virus (FeLV) in cats from an endemic area of zoonotic visceral leishmaniasis

The aim of the present study was to determine the coinfection of Leishmania sp. with Toxoplasma gondii, Feline Immunodeficiency Virus (FIV) and Feline Leukemia Virus (FeLV) in a population of cats from an endemic area for zoonotic visceral leishmaniasis. An overall 66/302 (21.85%) cats were found positive for Leishmania sp., with infection determined by direct parasitological examination in 30/302 (9.93%), by serology in 46/302 (15.23%) and by both in 10/302 (3.31%) cats. Real time PCR followed by amplicon sequencing successfully confirmed Leishmania infantum (syn Leishmania chagasi) infection. Out of the Leishmania infected cats, coinfection with FIV was observed in 12/66 (18.18%), with T. gondii in 17/66 (25.75%) and with both agents in 5/66 (7.58%) cats. FeLV was found only in a single adult cat with no Leishmania infection. A positive association was observed in coinfection of Leishmania and FIV (p<0.0001), but not with T. gondii (p>0.05). In conclusion, cats living in endemic areas of visceral leishmaniasis are significantly more likely to be coinfected with FIV, which may present confounding clinical signs and therefore cats in such areas should be always carefully screened for coinfections.