Risk factors associated with Mycoplasma capricolum subspecies capripneumoniae and morbillivirus infection in small ruminants in Tanzania.

Mortality of domestic small ruminants caused by contagious caprine pleuropneumonia (CCPP) and Peste des petits ruminants (PPR) is frequently reported in Tanzania. A cross-sectional survey was conducted between June, 2016 and July, 2017 to identify risk factors for small ruminants exposure to Mycoplasma capricolum subsp. capripneumoniae (M. capripneumoniae), the causative agent of CCPP, and small ruminant morbillivirus (SRMV), the causative agent of PPR. Antibody detection was done using competitive enzyme-linked immunosorbent assays (cELISA); similarly, a semi-structured questionnaire was administered in flocks where serum samples were collected. Individual seropositivity for M. capripneumoniae was 6.5% (n = 676) and 4.2% (n = 285) in goats and sheep respectively, whereas SRMV was 28.6% in goats (n = 676) and 31.9% in sheep (n = 285). Multivariable analysis indicated that mixing of flocks was a risk factor for exposure to M. capripneumoniae (χ2 = 3.9, df = 1, p = 0.05) and SRMV (χ2 = 6.3, df = 1, p = 0.01) in goats. Age was a protective factor for SRMV seropositivity in both goats (χ2 = 7.4, df = 1, p = 0.006) and sheep (χ2 = 10.2, df = 1, p = 0.006). SRMV seropositivity in goats was also influenced by grazing in contact with wild animals (χ2 = 5.9, df = 1, p = 0.02) and taking animals to the animal markets (χ2 = 8.2, df = 1, p = 0.004). M. capripneumoniae and SRMV are influenced by several risk factors and their control needs concerted efforts between stakeholders, which may include community involvement in mandatory vaccination and animals' movement control.

Contagious caprine pleuropneumonia - a comprehensive review.

Contagious caprine pleuropneumonia (CCPP) is a serious disease of goats, occasionally sheep and wild ruminants, caused by Mycoplasma capricolum subspecies capripneumoniae (Mccp). The disease is characterized by severe serofibrinous pleuropneumonia, very high morbidity (∼100%), and mortality (80-100%). CCPP affects goats in more than 40 countries of the world thereby posing a serious threat to goat farming around the globe. The characteristic clinical signs of CCPP are severe respiratory distress associated with sero-mucoid nasal discharge, coughing, dyspnea, pyrexia, pleurodynia, and general malaise. In later stages, severe lobar fibrinous pleuropneumonia, profuse fluid accumulation in pleural cavity, severe congestion of lungs and adhesion formation is observed. Mycoplasmal antigen interactions with host immune system and its role in CCPP pathogenesis are not clearly understood. CCPP is not a zoonotic disease. Diagnosis has overcome cumbersome and lengthy conventional tests involving culture, isolation, and identification by advanced serological (LAT, cELISA) or gene-based amplification of DNA (PCR, RFLP, and hybridization) and sequencing. The latex agglutination test (LAT) is rapid, simple, and better test for field and real-time diagnosis applicable to whole blood or serum and is more sensitive than the CFT and easier than the cELISA. Moreover, the studies on antibiotic sensitivity and exploration of novel antibiotics (fluoroquinolones, macrolides) can help in better therapeutic management besides preventing menace of antibiotic resistance. Re-visiting conventional prophylactic measures focussing on developing novel strain-based or recombinant vaccines using specific antigens (capsular or cellular) should be the most important strategy for controlling the disease worldwide.

Reproduction of contagious caprine pleuropneumonia reveals the ability of convalescent sera to reduce hydrogen peroxide production in vitro.

Contagious caprine pleuropneumonia (CCPP), caused by Mycoplasma capricolum subsp. capripneumoniae is a severe disease widespread in Africa and Asia. Limited knowledge is available on the pathogenesis of this organism, mainly due to the lack of a robust in vivo challenge model and the means to do site-directed mutagenesis. This work describes the establishment of a novel caprine challenge model for CCPP that resulted in 100% morbidity using a combination of repeated intranasal spray infection followed by a single transtracheal infection employing the recent Kenyan outbreak strain ILRI181. Diseased animals displayed CCPP-related pathology and the bacteria could subsequently be isolated from pleural exudates and lung tissues in concentrations of up to 109 bacteria per mL as well as in the trachea using immunohistochemistry. Reannotation of the genome sequence of ILRI181 and F38T revealed the existence of genes encoding the complete glycerol uptake and metabolic pathways involved in hydrogen peroxide (H2O2) production in the phylogenetically related pathogen M. mycoides subsp. mycoides. Furthermore, the expression of L-α-glycerophosphate oxidase (GlpO) in vivo was confirmed. In addition, the function of the glycerol metabolism was verified by measurement of production of H2O2 in medium containing physiological serum concentrations of glycerol. Peroxide production could be inhibited with serum from convalescent animals. These results will pave the way for a better understanding of host-pathogen interactions during CCPP and subsequent vaccine development.

Comparative RNomics and modomics in Mollicutes: prediction of gene function and evolutionary implications.

Stable RNAs are central to protein synthesis. Ribosomal RNAs make the core of the ribosome and provide the scaffold for accurate translation of mRNAs by a set of tRNA molecules each carrying an activated amino acid. To fulfill these important cellular functions, both rRNA and tRNA molecules require more than the four canonical bases and have recruited enzymes that introduce numerous modifications on nucleosides. Mollicutes are parasitic unicellular bacteria that originated from gram-positive bacteria by considerably reducing their genome, reaching a minimal size of 480 kb in Mycoplasma genitalium. By analyzing the complete set of tRNA isoacceptors (tRNomics) and predicting the tRNA/rRNA modification enzymes (Modomics) among all sequenced Mollicutes (15 in all), our goal is to predict the minimal set of RNA modifications needed to sustain accurate translation of the cell's genetic information. Building on the known phylogenetic relationship of the 15 Mollicutes analyzed, we demonstrate that the solutions to reducing the RNA component of the translation apparatus vary from one Mollicute to the other and often rely on co-evolution of specific tRNA isoacceptors and RNA modification enzymes. This analysis also reveals that only a few modification enzymes acting on nucleotides of the anticodon loop in tRNA (the wobble position 34 as well as in position 37, 3'-adjacent to anticodon) and of the peptidyltransferase center of 23S rRNA appear to be absolutely essential and resistant to gene loss during the evolutionary process of genome reduction.