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.     

Occurrence of 'Candidatus Mycoplasma turicensis' infection in domestic cats in Japan

We have examined the presence of hemoplasmas, hemotropic mycoplasmas, among domestic cats (Felis catus) in Japan by using a species specific PCR, and found 'Candidatus Mycoplasma turicensis', a recently recognized hemoplasma species. A total of 60 feline blood samples collected in 2004 and 2005 were subjected to PCR amplification for the detection of Mycoplasma haemofelis, 'Candidatus Mycoplasma haemominutum' and 'Candidatus Mycoplasma turicensis'. Six blood samples collected from domestic cats were found infected with the 'Candidatus M. turicensis'. All of them are also infected with other species of hemoplasmas, M. haemofelis and/or 'Candidatus M. haemominutum'. This is the first to demonstrate 'Candidatus M. turicensis' infections among cat population in Japan.     

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 cats (16.9 per cent) were positive for 'Candidatus M. haemominutum' alone, six (1.4 per cent) were positive for M. haemofelis alone and one (0.2 per cent) was positive for both. Logistic regression analysis indicated that older male cats were significantly more likely to be infected with 'Candidatus M. haemominutum', but there was no significant association between it and any of the haematological variables measured. M. haemofelis infection was uncommon in the anaemic cats sampled, and there were too few positive cases for multivariable analysis to be performed for M. haemofelis-positive status.     

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.     

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

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

Diagnosis of feline haemoplasma infection using a real-time PCR assay

Haemobartonella felis has been reclassified within the genus Mycoplasma as Mycoplasma haemofelis and 'Candidatus Mycoplasma haemominutum', collectively referred to as the feline haemoplasmas. A total of 78 cats from the Johannesburg area that had blood samples submitted to a private veterinary laboratory were tested using a real-time polymerase chain reaction (PCR) assay able to detect and distinguish the two feline haemoplasma (basonym Haemobartonella) species. All samples had been diagnosed with haemoplasma infection by cytological examination of blood smears. Statistical analysis was performed to evaluate associations between haemoplasma status, age, and haematological and biochemical parameters. On PCR assay 43 cats (55%) were haemoplasma negative, 25 (32.1%) positive for 'Candidatus Mycoplasma haemominutum', 5 (6.4%) positive for Mycoplasma haemofelis and 5 (6.4%) positive for both species. Significant inverse correlation was found between the amount of M. haemofelis DNA present in the blood and the haematocrit value. Cats that were positive for M. haemofelis showed macrocytic regenerative anaemia, monocytosis and thrombocytopaenia. This report documents the existence of both haemoplasma species in cats in South Africa.     

Prevalence of DNA of Mycoplasma haemofelis, 'Candidatus Mycoplasma haemominutum,' Anaplasma phagocytophilum, and species of Bartonella, Neorickettsia, and Ehrlichia in cats used as blood donors in the United States

OBJECTIVE: To identify the prevalence of DNA of Mycoplasma haemofelis; 'Candidatus Mycoplasma haemominutum'; Anaplasma phagocytophilum; and species of Bartonella, Neorickettsia, and Ehrlichia in blood of cats used as blood donors in the United States. DESIGN: Prospective study. ANIMALS: 146 cats that were active blood donors. PROCEDURES: Environmental history was requested for each blood-donor cat from which a blood sample (mixed with EDTA) was available. Polymerase chain reaction assays capable of amplifying the DNA of the microorganisms of interest following DNA extraction from blood were performed. RESULTS: Overall, DNA of one or more of the infectious agents was detected in blood samples from 16 of 146 (11%) feline blood donors. Twenty-eight laboratory-reared cats housed in a teaching hospital had negative results for DNA of all organisms investigated. The DNA of at least 1 infectious agent was amplified from blood samples collected from 16 of 118 (13.6%) community-source cats; assay results were positive for 'Candidatus M haemominutum,' M haemofelis, or Bartonella henselae alone or in various combinations. Of the community-source cats allowed outdoors (n = 61) or with known flea exposure (44), DNA for a hemoplasma or B henselae was detected in 21.3% and 22.7%, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: When community-source cats, cats allowed outdoors, or cats exposed to fleas are to be used as blood donors, they should be regularly assessed for infection with M haemofelis, 'Candidatus M haemominutum,' and Bartonella spp, and flea-control treatment should be regularly provided.     

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.     

Use of real-time PCR to detect Mycoplasma haemofelis and 'Candidatus Mycoplasma haemominutum' in the saliva and salivary glands of haemoplasma-infected cats

Feline haemoplasma infection can cause haemolytic anaemia. The natural method of transmission of haemoplasmas between cats is currently unknown but the nature of some of the risk factors for infection suggests that saliva may act as a mode of transmission. The aim of this study was to determine if Mycoplasma haemofelis (Mhf) and 'Candidatus Mycoplasma haemominutum' (CMhm) DNAs could be amplified from saliva and salivary gland samples collected from haemoplasma-infected cats.     

Prevalence of Mycoplasma haemofelis, 'Candidatus Mycoplasma haemominutum', Bartonella species, Ehrlichia species, and Anaplasma phagocytophilum DNA in the blood of cats with anemia

Hemoplasmas are known causes of anemia in some cats and some Bartonella species have been associated with anemia in people and in dogs. In this retrospective study, we used polymerase chain reaction (PCR) assays to determine the prevalence rates of Mycoplasma haemofelis, 'Candidatus M haemominutum', A phagocytophilum, Ehrlichia species, and Bartonella species DNA in the blood of cats with anemia and a control group of healthy cats. DNA of the organisms was amplified from 22 of 89 cats with anemia (24.7%) and 20 of 87 healthy cats (23.0%). DNA of a hemoplasma was amplified from 18 of 89 cats with anemia (20.2%) and 13 of 87 healthy cats (14.9%); DNA of a Bartonella species was amplified from five of 89 cats with anemia (5.6%) and seven of 87 healthy cats (8.0%). There were no statistically significant differences detected between groups.     

Diagnosis of feline haemoplasma infection in Australian cats using a real-time PCR assay

A total of 147 cats from the Sydney area of Australia that had blood samples submitted to veterinary laboratories were tested using a real-time polymerase chain reaction (PCR) assay able to detect and distinguish the two feline haemoplasma species. This sample number included two cats diagnosed with feline haemoplasma infection by routine blood smear examination. Statistical analysis was performed to evaluate associations between haemoplasma infection, age, sex, breed, haematocrit (HCT) values and anaemia status. One hundred and six cats (72.1%) were negative. Thirty-four cats (23.1%) were positive for 'Candidatus M. haemominutum', six cats (4.1%) were positive for M. haemofelis and one cat (0.7%) was positive for both species. Older, male, non-pedigree cats, with lower HCT values were more likely to be infected with 'Candidatus M. haemominutum'. Significant inverse correlation was found between the amount of M. haemofelis DNA present in the blood and the HCT value. This report documents the existence of, and prevalence of, both haemoplasma species in a sample of cats in Australia and is the first to use quantitative real-time PCR in a prevalence study for haemoplasma infection.     

First morphological characterization of 'Candidatus Mycoplasma turicensis' using electron microscopy

At least three haemotropic mycoplasmas have been recognized in cats: Mycoplasma haemofelis (Mhf), 'Candidatus Mycoplasma haemominutum' (CMhm) and 'Candidatus M. turicensis' (CMt). The latter was originally identified in a Swiss pet cat with haemolytic anaemia and shown to be prevalent in domestic cats and wild felids worldwide using molecular methods. So far, there has been no confirmatory morphological evidence of the existence of CMt presumably due to low blood loads during infection while CMhm has only been characterized by light microscopy with discrepant results. This study aimed to provide for the first time electron microscopic characteristics of CMt and CMhm and to compare them to Mhf. Blood samples from cats experimentally infected with CMt, CMhm and Mhf were used to determine copy numbers in blood by real-time PCR and for transmission and scanning electron microscopy. High resolution scanning electron microscopy revealed CMt and CMhm to be discoid-shaped organisms of 0.3 μm in diameter attached to red blood cells (RBCs). In transmission electron microscopy of CMt, an oval organism of about 0.25 μm with several intracellular electron dense structures was identified close to the surface of a RBC. CMhm and CMt exhibited similar morphology to Mhf but had a smaller diameter. This is the first study to provide morphological evidence of CMt thereby confirming its status as a distinct haemoplasma species, and to present electron microscopic features of CMhm.     

Survival of Mycoplasma haemofelis and 'Candidatus Mycoplasma haemominutum' in blood of cats used for transfusions

Blood transfusions are commonly administered to cats; associated risks include the transmission of various infectious diseases including Mycoplasma haemofelis (Mhf) and 'Candidatus Mycoplasma haemominutum' (Mhm). Blood transfusions in citrate-phosphate-dextrose-adenine (CPDA-1) solution are commonly administered immediately or stored for up to 1 month prior to administration. It is unknown whether Mhf or Mhm survive in this solution or temperature. The purpose of this study was to determine if Mhf or Mhm remain viable after storage in CPDA-1 for varying periods of time. The results provide evidence that transmission of hemoplasmas to na?ve cats occurs after administration of infected feline blood that has been stored in CPDA-1 solution for 1h (Mhf) and 1 week (Mhm). These findings support the recommendation that cats used as blood donors be screened for Mhf and Mhm infections by polymerase chain reaction (PCR) assay prior to use.     

Molecular detection of Mycoplasma haemofelis and 'Candidatus Mycoplasma haemominutum' Infection in cats by direct PCR using whole blood without DNA extraction

Detection of hemotropic Mycoplasma spp. infection was attempted in cats by PCR using whole blood without DNA extraction. A total 46 of 54 (85%) cats with suspected Mycoplasma spp. infection showed a positive reaction, corresponding completely with the results of standard PCR testing. The direct PCR assay was sensitive enough to detect more than 0.0061% parasitemia for ;C. M. haemominutum' and 0.0075% parasitemia for M. haemofelis. These data indicate that the direct PCR assay might be sufficient for use as a tool in clinical examinations.     

Feline hemoplasmas in Switzerland: identification of a novel species, diagnosis, prevalence, and clinical importance

Two feline hemotropic mycoplasma spp. (aka hemoplasma) have previously been recognized. We recently discovered a third novel species in a cat with hemolytic anemia, designated 'Candidatus Mycoplasma turicensis', which is closely related to rodent haemoplasmas. This novel species induced anemia after experimental transmission to two SPF cats. Three quantitative real-time PCR assays were newly designed and applied to an epidemiological study surveying the Swiss pet cat population. Blood samples from 713 healthy and ill cats were analyzed. Up to 104 parameters per cat (detailed questionnaire, case history, laboratory parameters and retroviral infections) were evaluated. 'Candidatus Mycoplasma haemominutum' infection was more prevalent (8.5%) than Mycoplasma haemofelis (0.5%) and 'Candidatus Mycoplasma turicensis' (1%). Hemoplasma infections were associated with male gender, outdoor access, and old age, but not with disease or anemia. Infections were more frequently found in the South and West of Switzerland. Several hemoplasma infected cats, some acutely infected, others co-infected with FIV or FeLV, showed hemolytic anemia indicating that additional factors might play a role in the pathogenesis of the disease.     

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.     

A feline hemoplasma, 'Candidatus Mycoplasma haemominutum', detected in dog in Japan

We examined for 'Candidatus Mycoplasma haemominutum' infection in 167 blood samples collected from domestic dogs between 2008 and 2009 in the Tohoku area, Japan, and found 5 (3.0%) were positive by PCR assay. This is the first demonstration of 'Candidatus Mycoplasma haemominutum', a feline haemotropic mycoplasma, in the dogs raised in Japan.     

Use of combined conventional and real-time PCR to determine the epidemiology of feline haemoplasma infections in northern Italy

Although knowledge of feline haemotropic mycoplasmas (haemoplasmas) has dramatically improved in recent years, some issues still remain to be elucidated. The aim of the current study was to evaluate the prevalence of feline haemoplasma infections in blood samples collected from cats in northern Italy. A convenience-sample of 307 cats (40 anaemic; 258 non-anaemic; nine with unknown haematocrit [HCT]) was investigated using polymerase chain reaction assays. Furthermore, the date of blood collection, signalment and clinicopathological data were retrospectively evaluated to assess predictors and risk factors for infection. Haemoplasma infections were highly prevalent in the sample investigated with an overall prevalence of 18.9% (95% confidence interval: 14.5-23.3%). The prevalence for the three feline haemoplasmas was 17.3% for 'Candidatus Mycoplasma haemominutum' (CMhm), 5.9% for Mycoplasma haemofelis (Mhf) and 1.3% for 'Candidatus Mycoplasma turicensis' (CMt). Feline immunodeficiency virus-positive status represented a risk factor for infection with an odds ratio of 4.19 (P=0.02). Moreover, a higher prevalence was observed in summer (odds ratio 1.78; P=0.04) which may be consistent with arthropod-borne disease transmission. Cats infected with Mhf showed significantly lower HCT (P=0.03), haemoglobin values (P=0.02) and red blood cell counts (P=0.04), lower mean corpuscular haemoglobin concentration (P<0.01) and higher white blood cell counts (P<0.01) when compared with non-infected cats.     

Bartonella henselae infection in splenectomized domestic cats previously infected with hemotropic Mycoplasma species

Cat scratch disease is caused by Bartonella henselae and the domestic cat represents its main reservoir. In immunocompromised patients, infection with B. henselae is characterized by more severe clinical forms than in non-immunocompromised individuals. The objective of the present study was to investigate the characteristics of B. henselae (Houston-I strain) infection in four splenectomized and three non-splenectomized cats, five of which were chronically infected with 'Candidatus Mycoplasma haemominutum'. No major clinical signs were observed in either group of cats. Cats in both splenectomized and non-splenectomized groups became bacteremic within a week post-inoculation. Although bacteremia was on average 10 days longer in the splenectomized cats, that difference was not statistically significant (P=0.72). In both groups, the level of bacteremia peaked within the same time frame; however, the level of bacteremia was about 10-fold higher in the splenectomized cats (P=0.007). Such a difference could be associated with a reduced immune response to the infection, especially a reduced ability to phagocytize Bartonella organisms in the splenectomized cats. Concurrent infection with 'Candidatus M. haemominutum' did not appear to alter the course of infection.     

Anemia associated with 'Candidatus Mycoplasma haemominutum' in a feline leukemia virus-negative cat with lymphoma

'Candidatus Mycoplasma haemominutum,' previously known as the small form of Haemobartonella felis (California species), is a hemotrophic parasite found on erythrocytes of infected cats. Although fleas are potential vectors, confirmatory studies are lacking. Healthy cats infected with 'Candidatus Mycoplasma haemominutum' generally do not have clinically significant anemia, but concurrent disease or immune suppression may predispose a cat to develop a life-threatening anemia, such as in the case reported here.