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

Molecular Survey and Genetic Characteristics of Vector-Borne Pathogens in Domestic Dogs from Four Regions of China

Canine vector-borne diseases are widely distributed around the world. They are transmitted by arthropods, and many seriously threaten the health of animals and humans. In China, our knowledge of Ehrlichia, Hepatozoon, and Mycoplasma species circulating in dogs is still poorly understood. Therefore, the aim of this study was to understand the prevalence and genetic characteristics of canine Ehrlichia spp., Hepatozoon spp., and Mycoplasma spp. in Chongqing (southwest), Fujian (southeast), Shandong (southeast), and Hubei (central) Provinces of China. Blood samples from healthy pet dogs were processed to detect Ehrlichia, Hepatozoon, and Mycoplasma DNA with PCR. Haplotype and phylogenetic analyses were performed on 18S rRNA sequences. Among 306 dogs, no Ehrlichia spp. or Mycoplasma spp. were detected, whereas one Hepatozoon sp. was detected in 10 (3.27%) of the animals. Only Hepatozoon canis was identified and was endemic to Chongqing (2.46%) and Hubei (8.77%). A haplotype analysis identified eight haplotypes among the H. canis isolates. A phylogenetic analysis showed that the H. canis isolates in this study clustered into four clades, together with isolates from different countries and hosts, forming a large group that was clearly separate from other Hepatozoon species. These findings provided new information on the epidemiological characteristics of canine vector-borne diseases in China and will be helpful in the development of efficient measures to safeguard the health and well-being of companion animals and their owners.

Advanced approaches for the diagnosis and chemoprevention of canine vector-borne pathogens and parasites-Implications for the Asia-Pacific region and beyond

Vector-borne pathogens (VBPs) of canines are a diverse range of infectious agents, including viruses, bacteria, protozoa and multicellular parasites, that are pernicious and potentially lethal to their hosts. Dogs across the globe are afflicted by canine VBPs, but the range of different ectoparasites and the VBPs that they transmit predominate in tropical regions. Countries within the Asia-Pacific have had limited prior research dedicated to exploring the epidemiology of canine VBPs, whilst the few studies that have been conducted show VBP prevalence to be high, with significant impacts on dog health. Moreover, such impacts are not restricted to dogs, as some canine VBPs are zoonotic. We reviewed the status of canine VBPs in the Asia-Pacific, with particular focus on nations in the tropics, whilst also investigating the history of VBP diagnosis and examining recent progress in the field, including advanced molecular methods, such as next-generation sequencing (NGS). These tools are rapidly changing the way parasites are detected and discovered, demonstrating a sensitivity equal to, or exceeding that of, conventional molecular diagnostics. We also provide a background to the armoury of chemopreventive products available for protecting dogs from VBP. Here, field-based research within high VBP pressure environments has underscored the importance of ectoparasiticide mode of action on their overall efficacy. The future of canine VBP diagnosis and prevention at a global level is also explored, highlighting how evolving portable sequencing technologies may permit diagnosis at point-of-care, whilst further research into chemopreventives will be essential if VBP transmission is to be effectively controlled.

Molecular detection of haemophilic pathogens reveals evidence of Candidatus Mycoplasma haemobos in dogs and parasitic ticks in central China

Background

In addition to Mycoplasma haemocanis and Candidatus Mycoplasma haematoparvum, a few hemoplasma species that mainly infect other livestock have been detected in dogs. ‘Candidatus Mycoplasma haemobos’ (Ca. M. haemobos) has been found in a variety of animals in China. The present study was aimed to investigate the occurrence of ‘Ca. M. haemobos’ infections in dogs and ticks collected from the Henan province, China.

Results

Overall, 55 dog blood samples and 378 ticks on skins were collected from anemic and healthy dogs, and these samples were subjected to PCR, sequence analysis, and identification. The results showed that Haemaphysalis longicornis (266) and Rhipicephalus (Boophilus) microplus (112) were the only two parasitic ticks on dogs. Molecular detection revealed that 163 M. haemocanis, 88 ‘Ca. M. haemobos’ and 32 Anaplasma platys positive amplicons could be amplified from dogs, H. longicornis and R. (B.) microplus. In addition, co-infections (M. haemocanis + A. platys and ‘Ca. M. haemobos’+ A. platys) could be also detected.

Conclusions

To the best of our knowledge, this is the first molecular evidence of ‘Ca. M. haemobos’ natural infection in dogs and tick species identified as H. longicornis and R. (B.) microplus from China.

Hemotropic Mycoplasma and Bartonella Species Diversity in Free-Roaming Canine and Feline from Luanda, Angola

Free-roaming dogs and cats represent potential reservoirs for zoonotic vector-borne pathogens shedding to the human population. Given the health impact of these pathogens, we searched free-roaming dogs and cats included in an animal population control program from Luanda, Angola, for Bartonella and hemotropic mycoplasma infection. We report the detection of Bartonella henselae (2/66; 3%), Candidatus Mycoplasma haemominutum (5/66; 7.5%) and Mycoplasma haemofelis (1/66; 1.5%) in cats. One dog was found positive for Mycoplasma haemocanis (1/20; 5%). This is the first report of Bartonella henselae infections in stray cats and of hemotropic mycoplasmas in cats and dogs from Angola. Despite the relatively small sample size, our results sustain the hypothesis of uncontrolled circulation of these agents in highly mobile synanthropic animal populations of Luanda. Population and vector control could contribute to reducing the likelihood for animal-to-animal and animal-to-human transmission.

Widespread Infection with Hemotropic Mycoplasmas in Free-Ranging Dogs and Wild Foxes Across Six Bioclimatic Regions of Chile

Blood samples of 626 rural dogs, 140 Andean foxes (Lycalopex culpaeus), and 83 South American grey foxes (L. griseus) from six bioregions of Chile spanning 3000 km were screened for Mycoplasma DNA by conventional PCR and sequencing. Risk factors of infection were inferred using Generalized Linear Mixed Models and genetic structure by network analyses. Overall, Mycoplasma haemocanis/Mycoplasma haemofelis (Mhc/Mhf) and Candidatus Mycoplasma haematoparvum (CMhp) observed prevalence was 23.8% and 12.8% in dogs, 20.1% and 7.2% in Andean foxes, and 26.5% and 8.4% in grey foxes, respectively. Both hemoplasmas were confirmed in all the bioregions, with higher prevalence in those where ticks from the Rhipicephalus sanguineus species group were absent. Candidatus M. haematominutum and a Mycoplasma sp. previously found in South American carnivores were detected in one fox each. Although the most prevalent Mhc/Mhf and CMhp sequence types were shared between dogs and foxes, network analysis revealed genetic structure of Mhc/Mhf between hosts in some regions. Male sex was associated with a higher risk of Mhc/Mhf and CMhp infection in dogs, and adult age with CMhp infection, suggesting that direct transmission is relevant. No risk factor was identified in foxes. Our study provides novel information about canine hemoplasmas with relevance in distribution, transmission routes, and cross-species transmission.

Spatial distribution and molecular epidemiology of hemotropic Mycoplasma spp. and Mycoplasma haemocanis infection in dogs from Rio de Janeiro, Brazil

This cross-sectional study aims to investigate the epidemiology and spatial distribution of hemotropic Mycoplasma spp. and Mycoplasma haemocanis in dogs from Rio de Janeiro, Brazil. Blood samples were collected at random from 437 household dogs. An epidemiological questionnaire was completed concerning the host characteristics as well as the environments in which they lived. A positivity frequency of 17.84% (78/437) was found for Mycoplasma spp. and 2% (9/437) for M. haemocanis in Rio de Janeiro, Brazil, through molecular detection based on the 16S rRNA sequence. According to the present study, dogs that live in households with the presence of rodents (odds ratio [OR] = 9.93; p-value = 0.02; confidence interval [CI]: 1.34-73.66) and wild animals (OR = 1.91; p-value = 0.03; CI: 1.06-3.42) are more likely to be infected with Mycoplasma spp.. Also, dogs with tick infestation (OR = 6.47; p-value = 0.007; CI: 1.63-25.60) have more chances to become infected with M. haemocanis. The spatial analysis disclosed a positive correlation between the Mycoplasma presence and tick infestation (global Moran index = 0.82; pseudo-p-value =0.001). The epidemiological findings support the hypothesis of Rhipicephalus sanguineus s.l. as the vector of M. haemocanis in the studied region and provide insightful information to prevent the Mycoplasma spp. infection in dogs from Rio de Janeiro.

Distribution and risk factors of canine haemotropic mycoplasmas in hunting dogs from southern Italy

Mycoplasma haemocanis (Mhc) and "Candidatus Mycoplasma haematoparvum" (CMhp) are the main haemoplasma species known to infect dogs. The aim of this study was to determine the prevalence of haemoplasma species infections in hunting dogs from southern Italy and assess related risk factors. 1,433 hunting dogs living in Campania region were tested by qPCR assay. The prevalence was 19.9 %; 13.1 % for Mhc and 11.4 % for CMhp; 4.6 % showed a coinfection with both haemoplasma species. Statistical analysis revealed living in Salerno province (Mhc: OR 3.72; CMhp: OR 2.74), hound (Mhc: OR 5.26; CMhp: OR 8.46) and mixed breed (Mhc: OR 3.38; CMhp: OR 2.80), rural environment (Mhc: OR 12.58; CMhp: OR 10.38), wild mammal hunting (Mhc: OR 8.73; CMhp: OR 8.32), cohabitation with other animals (Mhc: OR 2.82; CMhp: OR 2.78) and large pack size (Mhc: OR 2.96; CMhp: OR 1.61) as risk factors for haemoplasmas. Male gender (OR 1.44) and tick infestation history (OR 1.40) represented risk factors only for Mhc, while adult age (2-7 years - OR 2.01; > 7 years - OR 1.84) and large body size (OR 1.48) were associated only to CMhp. Mhc infection was significantly associated to Babesia vogeli (p < 0.05) and Hepatozoon canis (p < 0.001), while CMhp with H. canis (p < 0.001). This study adds information on haemoplasma species distribution in hunting dogs in southern Italy. Outdoor lifestyle and contact with wild fauna, through greater exposure to tick infestation, or possibly wounds acquired during hunting or fighting, could be factors contributing to haemoplasma infections.

Molecular Survey and Genetic Diversity of Hemoplasmas in Rodents from Chile

Even though hemotrophic mycoplasma (hemoplasma) infections are well documented in a wide variety of hosts worldwide, there is a gap in the knowledge aobut hemoplasmas in rodents. This study aimed to molecularly survey and investigate the genetic diversity of hemoplasmas in rodents from Chile. Synanthropic and wild rodents (n = 74) were captured in the southern province of Valdivia (Corral, Valdivia, Riñihue, and Reumén localities). Spleen samples were submitted to a conventional PCR for hemotrophic Mycoplasma spp. targeting the 16S rRNA gene (800 bp), followed by sequencing, phylogenetic, and genetic diversity analyses. The overall occurrence of hemotrophic mycoplasmas in rodents from Valdivia was 24.5% (18/74) [95% CI (14.5; 34.1)]. Hemoplasmas were detected in Mus musculus (1/4), Rattus norvegicus (1/16), Abrothrix longipilis (7/13), A. olivaceo (6/8), and Oligoryzomys longicaudatus (3/10). The nucleotide polymorphism analysis of the targeted 16S rRNA region showed low diversity, with two genotypes and a high identity to the variants detected in wild rodents from Brazil. Hemoplasmas are described for the first time in rodents from Chile with a moderate occurrence and low 16S rDNA genetic diversity within the sampled rodent population. The detected hemoplasma genotypes were specific to rodents and were not shared with other mammals.

Prevalence and molecular characterization of canine and feline hemotropic mycoplasmas (hemoplasmas) in northern Italy

BACKGROUND

Hemotropic mycoplasmas (hemoplasmas), the agents of infectious anemia, have been reported in dogs and cats. Little data are available on hemoplasma infections in Italy. The aim of this study was to evaluate the species of hemoplasmas and their prevalence in dogs and cats of northern Italy.

METHODS

Blood samples were obtained from 117 candidate blood donor dogs, 278 free-roaming dogs and 227 free-roaming cats in 2014 and 2015. Samples were first screened for hemoplasmas with a SYBR green real time PCR. The positive samples were confirmed by a second SYBR green real time PCR and sequencing. Co-infections were detected using species-specific SYBR green real time PCR.

RESULTS

The overall prevalence in dogs was 4.5% (18/395). Among the donors only one dog was positive for Mycoplasma haemocanis (0.8%). The overall prevalence of infection in free-roaming dogs was 6.1% (17/278), which was significantly higher than in candidate donors (P < 0.05). Both M. haemocanis (13/278; 4.7%) and "Candidatus M. haematoparvum" (4/278; 1.4%) were identified. In dogs, no significant association was found between hemoplasma infection and gender, age or origin. The overall prevalence in cats was 13.2% (30/227). All three feline hemoplasma species were detected, i.e. "Candidatus Mycoplasma haemominutum" (28; 12.3%), "Candidatus Mycoplasma turicensis" (11; 4.8%) and Mycoplasma haemofelis (9; 4.0%). Half of the infected cats were co-infected (15; 6.6%) with different species of hemoplasmas. Risk factor analysis confirmed that older age, male gender and FIV positivity are predisposing factors for hemoplasma infection in cats.

CONCLUSION

This study found that candidate blood donor dogs in northern Italy show a negligible risk for hemoplasma infection, confirming the appropriateness of the candidate selection criteria and the low prevalence in the study area. Accordingly, testing for hemoplasma should be considered optional for canine blood donor screening. Hemoplasma infection was instead common in free-roaming cats, and is expected to be non-negligible in owned cats with outdoor access. Feline candidates for blood donation will therefore need to be carefully selected.

Update on Canine and Feline Blood Donor Screening for Blood-Borne Pathogens

An update on the 2005 American College of Veterinary Internal Medicine (ACVIM) Consensus Statement on blood donor infectious disease screening was presented at the 2015 ACVIM Forum in Indianapolis, Indiana, followed by panel and audience discussion. The updated consensus statement is presented below. The consensus statement aims to provide guidance on appropriate blood‐borne pathogen testing for canine and feline blood donors in North America.

Occurrence and identification of hemotropic mycoplasmas (Hemoplasmas) in free ranging and laboratory rats (Rattus norvegicus) from two Brazilian zoos

BACKGROUND

Hemotropic mycoplasmas (hemoplasmas), bacteria belonging to the class Mollicutes, are obligatory red blood cell pathogens of a variety of animal species. They may cause acute anemia that is life-threatening or chronic disease that is clinically silent, but may interfere with results of experimental studies when using infected animals. Since these bacteria cannot be cultivated, molecular techniques are the gold standard for diagnosing an infection, investigating its prevalence, and describing new species. Mycoplasma coccoides and M. haemomuris are the most commonly recognized hemoplasmas in the blood of wild and laboratory rodents. Neither the epidemiology nor clinical and molecular characterization of hemoplasma infection in free-ranging rodents in Brazil has been previously reported. The aims of this study were to investigate the occurrence of hemoplasmas in free-ranging rats (Rattus norvegicus) captured in the Passeio Público and Curitiba Zoo and compare hematologic parameters of infected and non-infected animals.

RESULTS

Anti-coagulated blood samples collected from 43 free-ranging and 20 nursery rats were included in the study. Overall 63.5% were positive using SYBR® Green quantitative PCR (qPCR) of the 16S rRNA gene to screen for hemoplasma infection (72% among free-ranging rats; 45% among laboratory-raised rats). Sequencing of the qPCR products showed that all but one sample had >98% identity to M. haemomuris. Phylogenetic analysis based on a fragment of approximately 1300 bp of the 16S rRNA gene showed 99% identity to a new hemoplasma from European rats and 98% identity to a hemotropic mycoplasma described infecting a European harvest mouse (Micromys minutus). No statistically significant changes in hematologic parameters between infected and non-infected rats were found, confirming the low pathogenicity and/or silent characteristics of the infection.

CONCLUSIONS

Our findings suggest that hemoplasmas are likely endemic in rodent species in this region. The epidemiology, especially as it relates to the mode of transmission, needs to be further investigated as well as the possibility that other animal species, including humans, might become infected.

Prevalence of haemoplasma infections in stray cats in northern Italy

This study investigated the prevalence of feline haemoplasma infections in a number of stray cat colonies in Milan, Northern Italy. Blood samples from 260 stray cats were evaluated, with conventional PCR, for the presence of DNA associated with Mycoplasma haemofelis (Mhf) and "Candidatus Mycoplasma haemominutum" (CMhm). Odd ratios (OR) were calculated to identify risk factors for haemoplasma infections. PCR was positive in 86 out of 260 subjects (33.1%), with a prevalence of 10.8% (28/260 cats) for Mhf and 22.3% (58/260 cats) for CMhm. No coinfections were registered. There were significant associations between infections and season of sampling, that is, a negative association between winter sampling and a haemoplasma positive status (OR = 0.29, P = 0.001), or CMhm positive status (OR = 0.29, P = 0.01). Haemoplasma infections are common in stray cats in Milan. Thus, domestic cats with outdoor access should be routinely monitored and treated for ectoparasites to minimize risks of disease acquisition. Moreover, as these infections are transmitted via blood, feline blood donors from this area should be screened by PCR and preferably be drawn from a population of indoor cats regularly treated for fleas.