Haemofelis Infection Research Articles

Mycoplasma haemofelis infection and its correlation with feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) in cats in Southern Brazil

A cross-sectional study was conducted on 274 cats in Southern Brazil to estimate the prevalence of Mycoplasma haemofelis PCR, associated factors, and its correlation with ELISA for FeLV and FIV. The apparent prevalence of M. haemofelis was 6.6% (18/274) (95% CI: 3.6–9.5%), of which 33.3% (6/18) had co-infection with FeLV, 5.6% (1/18) with FIV, and 5.6% (1/18) with both. Male cats were more likely to be positive for M. haemofelis [OR: 7.07 (1.97–25.34)]. Only three M. haemofelis-positive cats showed related clinical changes, such as mucosal pallor. A statistically significant difference was observed between M. haemofelis-positive cats and the negative control group for age, hemoglobin concentration, packed cell volume, and rod neutrophil counts. Mycoplasma haemofelis is prevalent in southern Brazil, with a higher risk in male cats. Most cats could be classified as asymptomatic carriers since they were healthy.

Evaluating the association between blood genotype or phenotype and haemoplasma infection in UK and Italian cats.

In humans, blood groups are associated with varying prevalence of infections. The aim of this study was to determine if associations exist between the feline AB blood group system and haemoplasma infection. Data from two studies were combined. In the first study, DNA samples from 131 haemoplasma-infected and 132 haemoplasma-uninfected UK cats underwent pyrosequencing to determine their blood genotype as AA, Ab or bb. In the second study, blood samples from 160 Italian cats of known blood phenotype A, B or AB underwent PCR testing for feline haemoplasma species DNA. Haemoplasma infection was demonstrated in cats of all phenotypes and genotypes. A significantly higher number of Ab genotype cats tested positive for overall haemoplasma infection status (p = 0.04) and for Mycoplasma haemofelis infection (p = 0.03). Haemoplasma-infected Italian cats were few, possibly increasing the chance of type II error, and the presence of purebred cats in the sample population may have had a confounding effect. Feline haemoplasmas do not appear to preferentially use either blood type A or B antigens as attachment sites for erythrocyte colonisation. Further investigations in a larger number of haemoplasma-infected cats of known blood phenotype are warranted to explain the association between genotype Ab and haemoplasma infection.

Retrospective prevalence and associated risk factors of Mycoplasma haemofelis infection in owned cats.

Data on the prevalence and associated risk factors of naturally occurring haemoplasmosis in owned cats in Malaysia is limited. Being the most pathogenic of the three known feline haemoplasma species, Mycoplasma haemofelis (Mhf) infection was analysed from 2016 to 2019 to determine the periodical prevalence and associated risk factors in Northeastern Malaysia - Kelantan. Archived patient data of 77 clinically ill cats suspected of having M. haemofelis infection were reviewed in this study. Out of the 77 suspected cases, 53 (68.8%) were clinically diagnosed with haemoplasmosis amongst which 46 (59.7%) of the subpopulation were further confirmed with polymerase chain reaction (PCR). Risk factors for M. haemofelis infection (age, breed, ectoparasitism, household condition, roaming status, and sex) were analysed. There was no significant association of breed, ectoparasitism, household condition (number of cats) and occurrence of clinical signs with feline mycoplasmosis. Young, male and roamer cats were more likely to be diagnosed of mycoplasmosis than other categories of cats in this study. There was also a significant association between cats infected with 'Candidatus Mycoplasma haemominutum' with M. haemofelis. Thus, the coinfection of these two haemoplasma species is not uncommon. This study indicates that infection by M. haemofelis in anaemic cats is a common find in client-owned cats from Northeastern Malaysia. As the natural mode of transmission of haemoplasma infection remain unestablished, information in this study may highlight the importance of this disease and contribute to effective prevention and control strategies to minimize feline infectious anaemia (FIA) caused by M. haemofelis.

Haemotropic Mycoplasma species in pet cats in Latvia: a study, phylogenetic analysis and clinical case report.

ObjectivesThe aim of this study was to evaluate whether haemotropic Mycoplasma species are detected in pet cats in Latvia, to perform a phylogenetic analysis of the detected pathogens and to report a clinical case of feline infectious anaemia.MethodsPeripheral blood samples (n = 125) from pet cats were submitted; 99 samples were adequate to test for the presence of Mycoplasma species DNA by nested PCR. A clinical case was added in the later stages of the study. Positive isolates were subjected to phylogenetic analysis.ResultsThe prevalence of ‘Candidatus Mycoplasma haemominutum’ was 15% (n = 15/99), that of Mycoplasma haemofelis was 5% (5/99) and that of ‘Candidatus Mycoplasma turicensis’ was 2% (n = 2/99). Cases of coinfection included ‘Candidatus M haemominutum’ + M haemofelis (4%; n = 4/99) and ‘Candidatus M haemominutum’ + ‘Candidatus M turicensis’ (1%; n = 1/99). This is the first published report of M haemofelis infection in the Baltic states. Two different ‘Candidatus M turicensis’ isolates were discovered after phylogenetic analysis.Conclusions and relevanceThis report is the first of an autochthonous feline infectious anaemia case in the Baltic region. The prevalence of Mycoplasma species was similar to that in other northern European countries. Phylogenetic analysis revealed variability of the isolates; one of the ‘Candidatus M turicensis’ genotypes was detected for the first time in Europe.

Consecutive antibiotic treatment with doxycycline and marbofloxacin clears bacteremia in Mycoplasma haemofelis-infected cats

Mycoplasma haemofelis is the most pathogenic feline hemoplasma species and a causative agent of infectious hemolytic anemia in cats. Current treatment protocols are effective in reducing M. haemofelis blood loads and clinical signs but consistent bacteremia clearance is rarely achieved. The aim of this study was to develop an antibiotic treatment protocol capable of clearing M. haemofelis bacteremia. Doxycycline and marbofloxacin treatment protocols were evaluated in chronically M. haemofelis infected cats in two pre-experiments and a controlled treatment study (main experiment) using five treated and four untreated cats. The blood bacterial loads in the main experiment were monitored weekly by real-time PCR for 203 days. Cats were treated with doxycycline (5 mg/kg bid orally) for 28 days. Cats that remained M. haemofelis PCR-positive or became positive again (all 5 cats in the main experiment) were switched to marbofloxacin treatment (2 mg/kg sid orally) for 14 days; then, all cats were PCR-negative. Immunosuppression after the antibiotic treatment did not lead to reactivation of bacteremia. Fine needle aspirates of different organs and bone marrow collected before and after immunosuppression were PCR-negative. Overall, 5 cats cleared bacteremia with doxycycline alone (showing lower bacterial loads at the treatment start), while 10 cats needed to be switched to marbofloxacin. Based on our results, we recommend doxycycline treatment (10 mg/kg up to 28 days) for clearance of M. haemofelis infection and monitoring bacterial loads by real-time PCR. Only if bacteremia persists or reoccurs, antibiotic treatment should be switched to marbofloxacin (2 mg/kg sid for 14 days).

Lack of cross-protection against Mycoplasma haemofelis infection and signs of enhancement in "Candidatus Mycoplasma turicensis"-recovered cats.

“Mycoplasma haemofelis” and “Candidatus Mycoplasma turicensis” are feline hemoplasmas that induce hemolytic anemia. Protection from homologous re-challenge was recently demonstrated in cats recovered from primary infection. Here, we determined if cats recovered from “Cand. M. turicensis” infection were protected against infections with the more pathogenic M. haemofelis. Ten specified pathogen-free cats were exposed to M. haemofelis. Five of the ten cats had recovered from “Cand. M. turicensis” bacteremia (group A), and five cats were naïve controls (group B). No cross-protection was observed. By contrast, the “Cand. M. turicensis”-recovered cats displayed faster M. haemofelis infection onset (earlier PCR-positive and anemic) than the controls. No “Cand. M. turicensis” was detected in any cat. M. haemofelis shedding was observed in saliva, feces and urine. In both groups, evidence of a Th1 response was observed (high IFN-γ, low IL-4), but IL-10 levels were also high. In group A, total, CD4+ and CD8+ T cells increased within days after M. haemofelis exposure. At times of maximal bacteremia, macrocytic hypochromic anemia, neutropenia, monocytosis and a decrease in leukocyte, eosinophil, and lymphocyte counts and subsets thereof (B- and T-cells, CD4+, CD8+ and CD4+CD25+ cells) were particularly significant in group A. Moreover, an increase in protein concentrations, hypoalbuminemia and a polyclonal hypergammaglobulinemia were observed. Five of ten M. haemofelis-infected cats subsequently cleared bacteremia without antibiotic treatment. In conclusion, the study suggests that a previous hemoplasma infection, even when the cat has ostensibly recovered, may influence subsequent infections, lead to an enhancement phenomenon and other differences in infection kinetics.Electronic supplementary materialThe online version of this article (doi:10.1186/s13567-015-0240-x) contains supplementary material, which is available to authorized users.

Bir Kedide Mycoplasma haemofelis Enfeksiyonu ve Etkenin Taramalı Elektron Mikroskopi ile Görüntülenmesi

In this case report was aimed to the evaluation of Mycoplasma haemofelis infection and electron microscopic imaging in a cat. The material of present case was included a cat, three years old, male, referred to a history of anorexia, lethargy and dehydration. Clinically were defined dehydration, apathy, tachypnea, 38.2oC body temperature, murmur and tachycardia at the auscultation of heart. Mycoplasma haemofelis was detected at the peripheral smear and using PCR assay, and viewed with scanning electron microscopy. The patient was treated with doxycycline (Tetradox kapsul, Fako®) at a dose of 10 mg/kg/day orally for 14 days. The clinical condition of the cat was improved after treatment, which reduced the number of Mycoplasma haemofelis in blood smears, hematological and serum biochemical values were determined to be normal. To the best of authors’ knowledge, this case reports the first imaging of scanning electron microscopy of Mycoplasma haemofelis in cats that are naturally infected in Turkey.

A Case of Mycoplasma haemofelis Infection in a Korean Domestic Shorthair Cat

A six-months-old male Korean domestic shorthair cat was presented with fever, tachypnea, anorexia, and weight loss and admitted to Lee Seung Jin Animal Medical Center. During the routine physical examination, clinical signs such as mild dehydration and jaundice in the sclera were present. The complete blood count (CBC) and serum chemistry result showed anemia, thrombocytopenia, neutrophilia, and hyperbilirubinemia. Radiography revealed hepatomegaly and splenomegaly. Blood smear and microscopic examination showed severe hemolysis and anisocytosis. We sent the blood sample to the Neodin Veterinary Laboratory for PCR analysis to conduct a test to find out Ehlichia, feline hemoplasmas (haemobartonella), feline leukemia virus (FeLV), feline immunodeficiency virus (FIV) and anaplasma infection. According to PCR examination, the blood of this cat was positive for feline hemoplasmas (Mycoplasma haemofelis), but negative for other pathogens. The patient was prescribed doxycycline for 4 weeks and prednisolone for 1 week. The free of feline hemoplasmas infection was confirmed by PCR recheck after six months.

Establishment and characterization of a low-dose Mycoplasma haemofelis infection model

Hemotropic mycoplasma are small, cell-wall-free bacteria that can infect various mammalian species, including humans. They cannot be cultured in vitro; therefore, animal models play an important role, e.g. for pathogenesis studies. Mycoplasma haemofelis (Mhf) is the most pathogenic of the three feline hemotropic mycoplasma species; it is known to induce severe hemolytic anemia in infected cats. The aims of this study were to establish and characterize a low-dose Mhf transmission model. Five specified pathogen-free cats were subcutaneously exposed to 1000 copies of Mhf per cat corresponding to 0.05μL of infectious blood with 2×107 copies/mL as determined by real-time PCR. All cats became PCR-positive within 34 days post-exposure and reached a maximum blood Mhf load of 109 copies/mL, similar to previously reported high-dose infections. In a selected sample of modified Wright-stained blood smears, small epicellular coccoid structures on the surface of the red blood cells were identified by light microscopy. Additionally, using an Mhf rDnaK ELISA, seroconversion was demonstrated in all cats within 4–5 weeks after Mhf exposure. Four out of five cats developed anemia. While three cats showed only mild clinical signs of hemoplasmosis, one cat developed severe anemia and required antibiotic treatment. Our study demonstrated that minimal contact with Mhf infectious blood was sufficient for transmission of the infection and the induction of hemoplasmosis. This low-dose Mhf infection might more accurately mirror the natural route of infection, i.e., by arthropod vectors or aggressive interaction among cats. We therefore recommend this protocol for use in future animal model studies.

Genome of Mycoplasma haemofelis, unraveling its strategies for survival and persistence

Mycoplasma haemofelis is a mycoplasmal pathogen (hemoplasma) that attaches to the host's erythrocytes. Distributed worldwide, it has a significant impact on the health of cats causing acute disease and, despite treatment, establishing chronic infection. It might also have a role as a zoonotic agent, especially in immunocompromised patients. Whole genome sequencing and analyses of M. haemofelis strain Ohio2 was undertaken as a step toward understanding its survival and persistence. Metabolic pathways are reduced, relying on the host to supply many of the nutrients and metabolites needed for survival. M. haemofelis must import glucose for ATP generation and ribose derivates for RNA/DNA synthesis. Hypoxanthine, adenine, guanine, uracil and CMP are scavenged from the environment to support purine and pyrimidine synthesis. In addition, nicotinamide, amino acids and any vitamins needed for growth, must be acquired from its environment. The core proteome of M. haemofelis contains an abundance of paralogous gene families, corresponding to 70.6% of all the CDSs. This "paralog pool" is a rich source of different antigenic epitopes that can be varied to elude the host's immune system and establish chronic infection. M. haemofelis also appears to be capable of phase variation, which is particularly relevant to the cyclic bacteremia and persistence, characteristics of the infection in the cat. The data generated herein should be of great use for understanding the mechanisms of M. haemofelis infection. Further, it will provide new insights into its pathogenicity and clues needed to formulate media to support the in vitro cultivation of M. haemofelis.

Polymerase chain reaction survey of feline haemoplasma infections in Greece.

The aim of this study was to use real-time polymerase chain reaction assays to determine the prevalence of three haemoplasma species in cats from Greece and to evaluate possible associations between haemoplasma infection and age, gender, feline immunodeficiency virus/feline leukaemia virus (FIV/FeLV) status and packed cell volume (PCV). Ninety-seven cats (24 ill anaemic, 55 ill non-anaemic, 18 healthy non-anaemic) were included in the study. Twenty cats (20.6%) were haemoplasma positive; seven cats were infected only with Mycoplasma haemofelis, 10 were infected only with 'Candidatus Mycoplasma haemominutum' and three were co-infected with M haemofelis and 'Candidatus M haemominutum'. 'Candidatus Mycoplasma turicensis' was not detected. Haemoplasma infection was associated with older age (P=0.019). M haemofelis infection tended to be more common in anaemic cats (P=0.058). No association between gender and haemoplasma infection, or haemoplasma relative copy number and PCV, was detected. Retroviral infection rates were very low with only one FeLV proviral positive cat found.

Distribution of Mycoplasma haemofelis in blood and tissues following experimental infection

The aim of the study was to describe blood and tissue copy number distribution during Mycoplasma haemofelis infection and determine if sequestration of organisms in body tissues could explain blood copy number cycling in infected cats. Thirteen domestic–shorthaired cats were used. Blood samples were regularly collected, and at a differing time point post-infection for each cat, tissue samples also collected, for quantitative PCR (qPCR). Absolute haemoplasma copy numbers were calculated for all blood and tissue samples, as well as an estimation of the ratio of tissue haemoplasma copy number to that expected in the tissue if a positive qPCR result arose due to tissue blood supply alone. Cats with high or moderate M. haemofelis blood copy numbers at the time of tissue collection had fewer M. haemofelis copies in most tissues than expected due to the tissue blood supply alone; only splenic and lung tissues consistently contained more M. haemofelis. However tissues collected from cats at a time of very low M. haemofelis blood copy numbers, when putative copy number cycling nadirs were occurring, were usually qPCR negative. Hence no evidence of significant tissue M. haemofelis sequestration was found in this study to explain the copy number cycling reported with this feline haemoplasma species.

Description of outcomes of experimental infection with feline haemoplasmas: Copy numbers, haematology, Coombs’ testing and blood glucose concentrations

The aim of this study was to compare blood copy, haematological and glucose values between cats experimentally infected with either Mycoplasma haemofelis (Group HF: 10 cats), ‘Candidatus M. haemominutum’ (Group HM: 3 cats) or ‘Candidatus M. turicensis’ (Group TU: 3 cats). Blood samples were collected regularly up to 85 days post-infection (DPI) for haemoplasma real-time quantitative PCR, haematology, Coombs’ testing and blood glucose measurement. Statistical analysis was performed using a general linear model (ANOVA) appropriate for a repeated measures experiment with significance set as P<0.05. Cats in Group TU had significantly lower blood copy numbers than cats in Group HF (P<0.001) and HM (P<0.001). All Group HF cats developed anaemia (often severe), macrocytosis and evidence of erythrocyte-bound antibodies whereas Groups HM and TU cats did not. Group HF had significantly lower PCVs, haemoglobin concentrations and red blood cell counts, and significantly higher mean cell volumes, than Groups HM and TU. In Group HF, erythrocyte-bound antibodies reactive at 4°C (both IgM and IgG) appeared between 8 and 22 DPI and persisted for two to four weeks, whereas those reactive at 37°C (primarily IgG) appeared between 22 and 29 DPI and persisted for one to five weeks. In most cats antibodies appeared after the fall in haemoglobin started. Although Group TU had significantly lower glucose concentrations than Groups HF (P=0.006) and HM (P=0.027), mean blood glucose concentrations remained within the reference range in all groups. This study demonstrates that M. haemofelis infection, in contrast to ‘Candidatus M. haemominutum’ and ‘Candidatus M. turicensis’ infection, can result in a severe macrocytic anaemia and the development of cold and warm reactive erythrocyte-bound antibodies.

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.

The use of real-time PCR in the diagnosis and monitoring of Mycoplasma haemofelis copy number in a naturally infected cat

A 5-year-old male neutered cat was diagnosed with severe anaemia due to acute Mycoplasma haemofelis infection. Inflammatory respiratory disease was present concurrently. The cat was treated successfully using a fresh transfusion of whole blood and a 6 week course of doxycycline. The patient made a rapid recovery although the allergic airway disease subsequently required specific therapy consisting of inhaled fluticasone and salbutamol. Real-time quantitative PCR assays confirmed the presence of M. haemofelis DNA copies in the blood at presentation. Repeat PCR assays showed a reduction in copy number during treatment and negative PCR results were obtained both 91 and 425 days after presentation. The report describes, for the first time, the use of real-time PCR in the diagnosis and monitoring of natural M. haemofelis copy number, as well as the induction of long-term negative PCR status.

Use of a Taqman PCR to determine the response of Mycoplasma haemofelis infection to antibiotic treatment

A quantitative Taqman polymerase chain reaction (PCR) assay was used to evaluate the response of Mycoplasma haemofelis experimentally infected cats to three antibiotic treatment regimes. Sixteen cats were intravenously inoculated with M. haemofelis from a chronically infected donor. The cats were randomly assigned to one of four treatment groups each containing four cats: oral doxycycline at 10 mg/kg/day for 14 days, oral enrofloxacin at 5 mg/kg/day for 14 days, oral enrofloxacin at 10 mg/kg/day for 14 days, and an untreated control group. DNA, extracted from blood samples collected on days 0, 7, 14, 21, 25, 28, 32, 35, 42 and 54 post-inoculation (PI), was subjected to quantitative Taqman PCR. The M. haemofelis copy number was significantly lower in the doxycycline group ( P=0.008), the 5 mg/kg/day enrofloxacin group ( P=0.006) and the 10 mg/kg/day enrofloxacin group ( P=0.005) compared to the untreated control group. No significant differences were found between any of the three antibiotic treated treatment groups. All three antibiotic treatment regimes evaluated in this study were effective at reducing M. haemofelis copy number.

Use of a PCR assay to assess the prevalence and risk factors for Mycoplasma haemofelis and ‘Candidatus Mycoplasma haemominutum’ in cats in the United Kingdom

Blood samples from 426 healthy and sick cats in the UK were tested in a PCR assay for ‘Candidatus Mycoplasma haemominutum’ and Mycoplasma haemofelis (basonym Haemobartonella felis). Seventy-two of the...