First Molecular Evidence of Pathogens in Fleas Collected from Dogs in Northern Vietnam

Fleas are considered as hosts for a wide range of pathogens that cause emerging and re-emerging zoonotic diseases worldwide. Data on fleas and flea-borne pathogens (FBPs) in the international literature are limited in Vietnam. This study aimed to investigate the species of fleas and the presence of pathogens of interest in fleas in northern Vietnam using PCR and sequence analysis. Out of 200 dogs enrolled in this study, 20% were infested by the flea species Ctenocephalides felis felis. In total, 62 fleas (35 females and 27 males) collected from domestic dogs were molecularly screened for the detection of pathogens. Out of the screened fleas, 39 were positive for Rickettsia felis (62.9%), 9 for Candidatus Mycoplasma hemobos (14.52%), and 6 for Mycoplasma wenyonii (9.68%). This study shows the first molecular detection of the above-mentioned pathogens in fleas collected from the studied areas and the potential risk of infection with examined FBPs in northern Vietnam.

DETECÇÃO MOLECULAR DE HEMOPLASMAS EM BOVINOS E OVINOS EM SISTEMA DE CRIAÇÃO CONSORCIADA DO NORDESTE DO BRASIL – DADOS PRELIMINARES

Micoplasmas hemotrópicos (hemoplasmas) são microrganismos gram-negativos e que ficam aderidos aos eritrócitos de diversas espécies de mamíferos. Em pequenos ruminantes, Mycoplasma ovis, e em bovinos, Mycoplasma wenyonii e ‘Candidatus Mycoplasma haemobos’ são as espécies já descritas. Nessas espécies animais a transmissão dos hemoplasmas pode estar relacionada à infestação por carrapatos ou picadas de moscas hematófagas. A infecção por hemoplasmas pode causar anemia hemolítica aguda, porém os sinais clínicos diferem de acordo com a espécie de hemoplasma envolvido, do animal parasitado, idade e sistema de produção em que é criado. Embora a hemoplasmose tenha sido relatada causando perdas econômicas significativas na criação de ruminantes em todo o mundo, dados de hemoplasmas em sistema de criação consorciada são inexistentes. Assim, o objetivo deste estudo é determinar a prevalência de hemoplasmas em bovinos e pequenos ruminantes provenientes de um sistema de criação consorciada no nordeste do Brasil. Até o momento, um total de 15 amostras (10 ovinos e cinco bovinos) foram triadas utilizando um protocolo de PCR para o gene 16S rRNA de hemoplasmas. As amostras positivas foram submetidas a uma PCR para o gene 23S rRNA de hemoplasmas. Todas as amostras foram positivas para o gene endógeno gliceraldeído 3-fosfato desidrogenase (gapdh). Todos as amostras de ovinos foram negativas para hemoplasmas. Três de cinco (60%) bovinos foram positivos para Mycoplasma spp. O estudo envolverá a triagem das amostras por PCR em tempo real.

Bovines Harbor a Diverse Array of Vector-Borne Pathogens in Northeast Algeria

Arthropod-borne hemoparasites represent a serious health problem in livestock, causing significant production losses. Currently, the evidence of Anaplasma spp., Theileria spp., Babesia spp., and hemotropic Mycoplasma spp. in Algeria remains limited to a few scattered geographical regions. In this work, our objectives were to study the prevalence of these vector-borne pathogens and to search other agents not yet described in Algeria as well as the identification of statistical associations with various risk factors in cattle in the northeast of Algeria. Among the 205 cattle blood samples tested by PCR analysis, 42.4% positive results were obtained for at least one pathogen. The overall rates of Anaplasma spp., Theileria/Babesia spp., and Mycoplasma spp. in the cattle sampled were respectively 30.7%, 18.5%, and 2.9%; co-infections with multiple species was also detected. Anaplasma spp. and Theileria/Babesia spp. were detected at a higher rate in cattle under 3 years old, according to univariate analysis. Anaplasma spp. DNA was detected more frequently in our sample in cattle living in semi extensive farming. Our study provides additional data about Anaplasma spp., Theileria/Babesia spp. and reveals for the first time that Mycoplasma wenyonii and ‘Candidatus Mycoplasma hemobos are present in cattle in Northeast Algeria.

A comparative genomics and immunoinformatics approach to identify epitope-based peptide vaccine candidates against bovine hemoplasmosis

Mycoplasma wenyonii and ‘Candidatus Mycoplasma haemobos’ have been described as major hemoplasmas that infect cattle worldwide. Currently, three bovine hemoplasma genomes are known. The aim of this work was to know the main genomic characteristics and the evolutionary relationships between hemoplasmas, as well as to provide a list of epitopes identified by immunoinformatics that could be used as vaccine candidates against bovine hemoplasmosis. So far, there is not a vaccine to prevent this disease that impact economically in cattle production around the world.In this work, we used comparative genomics to analyze the genomes of the hemoplasmas so far reported. As a result, we confirm that ‘Ca. M haemobos’ INIFAP01 is a divergent species from M. wenyonii INIFAP02 and M. wenyonii Massachusetts. Although both strains of M. wenyonii have genomes with similar characteristics (length, G+C content, tRNAs and position of rRNAs) they have different structures (alignment coverage and identity of 51.58 and 79.37%, respectively).The correct genomic characterization of bovine hemoplasmas, never studied before, will allow to develop better molecular detection methods, to understand the possible pathogenic mechanisms of these bacteria and to identify epitopes sequences that could be used in the vaccine design.

First Molecular Detection and Characterization of Hemotropic Mycoplasma Species in Cattle and Goats from Uganda

Hemoplasmas (hemotropic mycoplasmas) are small pleomorphic bacteria that parasitize the surface of red blood cells of several mammalian species including cattle, goats, and humans, causing infectious anemia. However, studies on hemoplasmas have been neglected and to date, there are no studies on bovine and caprine hemoplasmas in Uganda or the entire East African region. In this study, a polymerase chain reaction (PCR) assay targeting the 16S rRNA gene was used to investigate the presence of hemoplasma in 409 samples (cattle = 208; goats = 201) collected from Kasese district, western Uganda. Results showed that 32.2% (67/208) of cattle samples and 43.8% (88/201) of goat samples were positive for hemoplasmas. Sequencing analysis identified Candidatus Mycoplasma haemobos and Mycoplasma wenyonii in cattle, while Candidatus Mycoplasma erythrocervae and Mycoplasma ovis were identified in goats. Statistical analysis showed that goats were at a higher risk of infection with hemoplasmas compared with cattle. To the best of our knowledge, this is the first molecular evidence of hemoplasmas in bovine and caprine animals in Uganda and the entire east African region.

Molecular detection of bovine hemotrophic mycoplasmas in Mexico

The presence of hemoplasmas Candidatus Mycoplasma haemobos and Mycoplasma wenyonii that infect bovine cattle has been reported during the last years. Hemoplasmas may affect animal health either alone or in coinfections with other microorganisms, resulting in anemia and other clinical signs. In Mexico, only Ca. M. haemobos has been detected in cattle; in this work, we report for the first time in our country the presence of M. wenyonii in animals from different geographical sources amd we detected both hemoplasmas by duplex PCR. Also, by single end-point PCR, we found Ca. M. haemobos and M. wenyonii in 96% and 96.29% of the blood samples, respectively. Both hemoplasmas were detected in 50% of the samples analyzed, which suggest that the duplex PCR developed in this work might improve if some modifications are performed. This molecular detection method will provide valuable information to know the health condition of national cattle to prevent pathogen dispersion.