Contagious caprine pleuropneumonia - a comprehensive review

A molecular epidemiological investigation of contagious caprine pleuropneumonia in goats and captive Arabian sand gazelle (Gazella marica) in Oman

BACKGROUND

Contagious caprine pleuropneumonia (CCPP) is a fatal WOAH-listed, respiratory disease in small ruminants with goats as primary hosts that is caused by Mycoplasma capricolum subspecies capripneumoniae (Mccp). Twelve CCPP outbreaks were investigated in 11 goat herds and a herd of captive Arabian sand gazelle (Gazella marica) in four Omani governorates by clinical pathological and molecular analysis to compare disease manifestation and Mccp genetic profiles in goats and wild ungulates.

RESULTS

The CCPP forms in diseased and necropsied goats varied from peracute (5.8%), acute (79.2%) and chronic (4.5%) while all of the five necropsied gazelles showed the acute form based on the clinical picture, gross and histopathological evaluation. Colonies of Mccp were recovered from cultured pleural fluid, but not from lung tissue samples of one gazelle and nine goats and all the isolates were confirmed by Mccp-specific real time PCR. Whole genome-single nucleotide polymorphism (SNP) analysis was performed on the ten isolates sequenced in this study and twenty sequences retrieved from the Genbank database. The Mccp strains from Oman clustered all in phylogroup A together with strains from East Africa and one strain from Qatar. A low variability of around 125 SNPs was seen in the investigated Omani isolates from both goats and gazelles indicating mutual transmission of the pathogen between wildlife and goats.

CONCLUSION

Recent outbreaks of CCPP in Northern Oman are caused by Mccp strains of the East African Phylogroup A which can infect goats and captive gazelles likewise. Therefore, wild and captive ungulates should be considered as reservoirs and included in CCPP surveillance measures.

An update on novel taxa and revised taxonomic status of bacteria isolated from non-domestic animals described in 2022

Numbers of new and revised microbial taxa are continuously expanding, and the rapid accumulation of novel bacterial species is challenging to keep up with in the best of circumstances. With that in mind, following the template of reports on prokaryotic species isolated from humans, this is now the second publication summarizing new and revised taxa in non-domestic animal species in the Journal of Clinical Microbiology. The majority of new taxa were obtained as part of programs to identify bacteria from mucosal surfaces and the gastrointestinal tract from healthy wildlife. A few notable bacteria included new Erysipelothrix spp. from mammalian and aquatic sources and a novel Bartonella spp. isolated from a rodent, both of which could be considered members of emerging and re-emerging genera with pathogenic potential in humans and animals.

Comparative untargeted and targeted metabonomics reveal discriminations in metabolite profiles between Mycoplasma capricolum subsp. capripneumoniae and Mycoplasma capricolum subsp. capricolum

Background

Mycoplasmas are among the smallest prokaryotic microbes that can grow and proliferate on non-living media. They have reduced genomes, which may be associated with a concomitant reduction in their metabolic capacity. Mycoplasma capricolum subsp. capripneumoniae (Mccp) and Mycoplasma capricolum subsp. capricolum (Mcc), both belong to the Mycoplasma mycoides cluster, are significant important pathogenic Mycoplasma species in veterinary research field. They share high degree of genome homology but Mcc grows markedly faster and has higher growth titer than Mccp.

Methods

This study investigated the metabolites of these two pathogenic bacteria from the middle and late stages of the logarithmic growth phase through liquid chromatography-mass spectrometry-based metabolomics and targeted energy metabolomics. The multivariate analysis was conducted to identify significant differences between the two important Mycoplasma species.

Results

A total of 173 metabolites were identified. Of them, 33 and 34 metabolites involved in purine and pyrimidine, pyruvate metabolism, and amino acid synthesis were found to significantly differ in the middle and late stages, respectively. The abundance of fructose 1,6-bisphosphate, ADP, and pyruvate was higher in Mcc than in Mccp during the whole logarithmic period. Lactate was upregulated in slow-growing Mccp. The pH buffering agent N-[2-hydroxyethyl]piperazine-N'-[2-ethanesulfonic acid] added to media effectively prevented pH reduction and increase bacterial viability and protein biomass. The multivariate analysis revealed that the two Mycoplasma species significantly differed in glucose metabolism, growth factor transport and metabolism, cholesterol utilization, and environmental regulation.

Conclusion

The study data are beneficial for understanding the metabolomic characteristics of these two crucial Mycoplasma species and shedding more light on mycoplasma metabolism, and serve as a resource for the pathogenesis and development of related vaccines.

Risk factors associated with contagious caprine pleuropneumonia in goats of Amhara region, Ethiopia

Contagious caprine pleuropneumonia (CCPP) is a serious contagious disease of goats, sheep and wild ruminants caused by Mycoplasma capricolum subspecies capripneumoniae. The disease is known for its high mortality, morbidity and economic losses. A cross-sectional study using multistage cluster sampling technique was conducted in Amhara region from January 2019 to July 2019 to estimate seroprevalence and identify risk factors of CCPP occurrence in the region. A total of 2080 goats from 61 villages and 12 districts of the region were tested for CCPP serostatus using Competitive Enzyme-Linked Immunosorbent Assay (C-ELISA). A multilevel mixed-effect logistic regression model was used to identify risk factors of CCPP seropositivity at animal and flock-level. The serum sample results revealed an overall animal level seroprevalence of 5.1% (95% CI: 3.8-6.6) and flock-level prevalence of 26.0% (95% CI: 19.7-33.4). At individual animal level, presence of other health problems (OR = 45.9 (95% CI: 25.3-83.4)), age (adult age (OR = 6.2 (95% CI:3.4-11.4)) and old age (OR = 13.1 (95% CI: 6.2-27.8))), and breed type (Afar (OR= 32.3 (95% CI: 2.9-366.1)), Central highland (OR=13.7 (95% CI: 1.3-140.6)), and western highland (OR=16.2 (95% CI: 1.4-185.7))) were identified as risk factors for CCPP seropositivity. In contrast, contact with other flocks (OR = 59.9 (95% CI: 6.1-585.6)), presence of trade route (OR = 3.1 (95% CI: 1.0-9.1)) and presence of sheep (OR = 2.6 (95% CI: 1.2-5.7)) were flock-level risk factors for CCPP seropositivity. Generally, CCPP appears to be common among goats of Amhara region. Goat flocks dominated with older age animals; breeds of Afar, central highland, and western highland; raise with sheep; have contact with other flocks; and kept along trade routes are more at risk for CCPP. Hence, awareness creation to the producers, movement control, and regular prophylactic vaccination should be considered to control CCPP in Amhara region.

First identification of Mycoplasma capricolum subspecies capripneumoniae in goats in Iran

Mycoplasma capricolum subspecies capripneumoniae (Mccp) is the etiological agent of caprine contagious pleuropneumonia (CCPP) disease. The CCPP is one of the most severe diseases of goats. A herd of 2,000 goats located in the countryside of Tehran city, Iran, was examined for the study in August 2021. In history taking, observation, inspection and clinical examination, high case fatality rate (46.00%) due to respiratory distress and high morbidity of pleuropneumonia (15.00%) syndrome were recorded. Accordingly, ten carcasses of goats were dissected. The epidemiological pattern of the disease, clinical examination findings and the signs of necropsy of dead patients were suspected to CCPP. Four lung samples of necropsied goats were sent to the laboratory for PCR test and in all of them, Mccp was detected and CCPP was also confirmed. The disease was controlled by two measures: (a) the whole herd was first treated with antibiotics (florfenicol and tylosin) and (b) then the Pulmovac-In vaccine was then administered. This study is the first documented report of CCPP occurrence caused by Mccp in Iran and shows the importance of availability of effective vaccines to control and prevention of CCPP.

Immune and Oxidative Response against Sonicated Antigen of Mycoplasma capricolum subspecies capripneumonia-A Causative Agent of Contagious Caprine Pleuropneumonia

Vaccines are vital for prevention and control of mycoplasma diseases. The exploration of a vaccine candidate for the development of a vaccine is imperative. The present study envisages the evaluation of immune and oxidative response against an adjuvanted, sonicated antigen of Mycoplasma capricolum subsp. capripneumonia in male Angora rabbits (1 year old, 2 kg) divided in four groups, each having six animals. Group 1 was the healthy control and received 1 mL PBS via subcutaneous route. Group 2 was administered 1 mL of saponin-adjuvanted and -sonicated antigen, Group 3 was given 1 mL of montanide ISA 50-adjuvanted and-sonicated antigen, and Group 4 was given 1 mL of standard vaccine via subcutaneous route. Animals were evaluated for cellular and humoral immune response and oxidative parameters at 0, 7, 14, 21, and 28 days of the study. Total leukocytic, neutrophilic, and basophilic counts showed a significant (p < 0.05) increase in vaccinated groups compared to the healthy group on most of the intervals. TNF-α levels were significantly (p < 0.05) higher in the Group 2 than the Group 1 at all the time intervals and more comparable to Group 4 than Group 3. IL-10 levels were significantly (p < 0.05) higher in vaccinated groups compared to the healthy group on days 14, 21, and 28, but were lower in Group 3 than in Group 2 and Group 4. More hypersensitivity as inflammation and histopathological cellular infiltration in the ear was produced in Group 2 and Group 4 than in Group 3. IgG levels were significantly (p < 0.05) higher in Group 2 and Group 4 than in Group 3 on days 14 and 21. Antibody titers were comparatively higher in Group 4, followed by Group 2 and 3, than Group 1. Significantly (p < 0.05) higher oxidant and lower antioxidant values were noted in Group 2 and 4 compared to Group 3 and Group 1 on most of the intervals. The TLC and antibody titer showed increasing trend throughout the trial, whereas TNF-α, IgG, L, M and E started decreasing from day 14, and IL-10, N and B started decreasing from day 21. This study concludes that the saponin-adjuvanted and-sonicated antigen induces comparatively higher immune response than montanide but is associated with oxidative and inflammatory reactions.

Seroepidemiology of selected transboundary animal diseases in goats in Zambia

Transboundary pathogens of goats present significant constraints to the livelihoods of millions of farmers in countries such as Zambia. Consequently, this study aimed to investigate the seroprevalence of Mycoplasma capricolum subsp. capripneumoniae (Mccp), foot and mouth disease virus (FMDV), Brucella spp., Crimean Congo haemorrhagic fever virus (CCHFV), and Rift Valley fever virus (RVFV) in Zambian goats. Another aim was to identify associations between seroprevalence and different predictor variables, such as trade and border proximity. From September to October 2019, 962 serum samples were collected from goats in seven Zambian districts, four of which have an international border while the remaining three do not. A questionnaire survey was conducted with each household, focusing on trade routines, management strategies and herd disease history. Animal-level seroprevalence adjusted for herd-level clustering was 8.2 % (95 % confidence interval [CI] 7.5-9.0) for Mccp, 12.9% (95% CI 12.0-13.7) for FMDV, 13.0 % (95% CI 12.1-13.9) for Brucella spp., 3.3 % (95% CI 2.8-3.7) for CCHFV, and 0.4 % (95 % CI 0.3-0.7) for RVFV. The association between herd-level seroprevalence and border proximity and trade appeared negligible, with the exception of selling goats at least twice a year which was identified as a potential risk factor for Brucella spp. (OR 4.1, 95 % CI 1.1-16.0, p = 0.040). In addition, a positive association between herd-level seroprevalence of FMDV and a herd size of 21 goats or more (OR 3.3, 95 % CI 1.0-11.1, p = 0.049) was detected. Also, positive associations between animal-level seroprevalence of Brucella spp. and increasing age (OR 7.7, 95 % CI 1.5-40.7, p = 0.016), and CCHFV and keeping pigs in the household (OR 2.7, 95 % CI 1.0-7.1, p = 0.044), were found. For FMDV (OR 3.8, 95 % CI 1.4-10.9, p = 0.011) and Brucella spp. (OR 4.5, 95 % CI 1.2-17.3, p = 0.031) on the other hand, animal-level seroprevalence was significantly higher in households without pigs. To the best of the authors' knowledge, this is the first study to describe the presence of antibodies for CCPP and CCHF in the Zambian goat population. While the association between seroprevalence and trade and border proximity generally appeared negligible, it is recommended that their influence is further evaluated in future studies, preferably through in-depth longitudinal studies incorporating impacts of different biosecurity measures and trade variations, linked to for example seasonality and trade peaks.

Development of Immunochromatographic Assay for the Rapid Detection of Mycoplasma capricolum subsp. capripneumoniae Antibodies

Mycoplasma capricolum subsp. capripneumoniae (Mccp) is the cause of contagious caprine pleuropneumonia (CCPP), which is a highly significant respiratory disease in goats leading to significant economic losses in Africa and Asia. Currently available procedures for the diagnosis of CCPP have some limitations in sensitivity, specificity, operation time, requirement of sophisticated equipment or skilled personnel, and cost. In this study, we developed a rapid, sensitive, and specific colloidal gold-based immunochromatographic assay (GICA) strip for the efficient on-site detection of antibodies against Mccp in the serum within 10 min. For the preparation of this colloidal GICA strip, recombinant P20 protein, the membrane protein of Mccp, was expressed by Escherichia coli prokaryotic expression system after purification was used as the binding antigen in the test. The rabbit anti-goat immunoglobulin G labeled with the colloidal gold was used as the detection probe, whereas the goat anti-rabbit immunoglobulin G was coated on the nitrocellulose membrane as the control line. The concentration of the coating antibody was optimized, and the effectiveness of this colloidal GICA strip was evaluated. Our results proved that the detection limit of the test strip was up to 1:64 dilutions for the Mccp antibody-positive serum samples with no cross-reactivity with other pathogens commonly infecting small ruminants,including goat pox virus, peste des petits ruminants virus, foot-and-mouth disease virus type A, or other mycoplasmas. Moreover, the colloidal GICA strip was more sensitive and specific than the indirect hemagglutination assay for the detection of Mccp antibodies. The 106 clinical serum samples were detected by the colloidal GICA strip compared with the complement fixation test, demonstrating an 87.74% concordance with the complement fixation test. This novel colloidal GICA strip would be an effective tool for the cost-effective and rapid diagnosis of CCPP in the field.

Minimalistic mycoplasmas harbor different functional toxin-antitoxin systems

Mycoplasmas are minute bacteria controlled by very small genomes ranging from 0.6 to 1.4 Mbp. They encompass several important medical and veterinary pathogens that are often associated with a wide range of chronic diseases. The long persistence of mycoplasma cells in their hosts can exacerbate the spread of antimicrobial resistance observed for many species. However, the nature of the virulence factors driving this phenomenon in mycoplasmas is still unclear. Toxin-antitoxin systems (TA systems) are genetic elements widespread in many bacteria that were historically associated with bacterial persistence. Their presence on mycoplasma genomes has never been carefully assessed, especially for pathogenic species. Here we investigated three candidate TA systems in M. mycoides subsp. capri encoding a (i) novel AAA-ATPase/subtilisin-like serine protease module, (ii) a putative AbiEii/AbiEi pair and (iii) a putative Fic/RelB pair. We sequence analyzed fourteen genomes of M. mycoides subsp. capri and confirmed the presence of at least one TA module in each of them. Interestingly, horizontal gene transfer signatures were also found in several genomic loci containing TA systems for several mycoplasma species. Transcriptomic and proteomic data confirmed differential expression profiles of these TA systems during mycoplasma growth in vitro. While the use of heterologous expression systems based on E. coli and B. subtilis showed clear limitations, the functionality and neutralization capacities of all three candidate TA systems were successfully confirmed using M. capricolum subsp. capricolum as a host. Additionally, M. capricolum subsp. capricolum was used to confirm the presence of functional TA system homologs in mycoplasmas of the Hominis and Pneumoniae phylogenetic groups. Finally, we showed that several of these M. mycoides subsp. capri toxins tested in this study, and particularly the subtilisin-like serine protease, could be used to establish a kill switch in mycoplasmas for industrial applications.

A mini-review on diagnosis of contagious caprine pleuropneumonia

Diagnosis of contagious caprine pleuropneumonia is imperative for timely detection and devising interventions that prevent disease spread and loss to farmers. Diagnosis of contagious caprine pleuropneumonia involves clinical signs, gross morphological lesions on postmortem, histopathology, culture and isolation, hematological, biochemical, serological and molecular diagnostic tests. Culture and isolation confirms the disease however it has been costly, cumbersome and difficult owing to the requirements of specific media, slow and difficult growth of causative agent Mycoplasma capricolum subsp. capripneumoniae. With the recent developments, diagnosis has comparatively eased by novel readymade media, advanced serological latex agglutination test (LAT), competitive enzyme linked immunosorbent assay (cELISA) or gene-based amplification of DNA, viz. polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), hybridization and sequencing than the cumbersome and lengthy conventional tests; however they have financial implications and require sophisticated laboratory infrastructure and technical manpower. 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 compliment fixation test (CFT) and easier than the cELISA. PCR and monoclonal antibody based ELISA being specific aid to confirmation of CCPP. Future thrust is on developing rapid, sensitive, and specific tests that are cheap and convenient for field application.

Alterations in acid-base balance, blood gases, and hematobiochemical profiles of whole-blood and thoracic fluid in goats with contagious caprine pleuropneumonia

Background and Aim:

Contagious caprine pleuropneumonia (CCPP) is a highly contagious and fatal disease affecting goats and some wild ruminants. It is a cause of major economic losses in the goat industry in Africa, Asia, and the Middle East. This study aimed to investigate the acid-base balance, blood gases, and hematobiochemical profiles of whole-blood and fluid collected from the thoracic cavity in goats with CCPP.

Materials and Methods:

Fifty-five goats suffering from weight loss, anorexia, dyspnea, polypnea, cough, and nasal discharges due to CCPP were studied. Twenty-five healthy goats were used as controls. Diseased animals were enrolled in this study based on a positive serological latex agglutination test (LAT) that confirmed the detection of Mycoplasma capricolum subsp. capripneumoniae. The control goats were enrolled based on a negative result of the LAT.

Results:

Compared with a mean value of 7.38±0.04 in controls, the pH in the diseased group was 7.41±0.05. The blood pressure of carbon dioxide (PCO₂), pressure of oxygen (PO₂), base excess (BE), bicarbonate (HCO₃), total carbon dioxide (TCO₂), and saturation of oxygen (SO₂) were lower in goats with CCPP than in controls. However, the anion gap (AnGap) was higher in the diseased goats than in the healthy ones. Compared with the levels in blood samples, the thoracic fluid PCO₂, PO₂, BE, and SO₂ were higher while pH, HCO₃, TCO₂, and AnGap were lower. Compared with the findings in healthy goats, hematological alterations included significant increases in white blood cells and neutrophils, and a significant decrease in the red blood cell count. In the thoracic fluid, neutrophilic leukocytosis was a remarkable finding. The serum concentrations of globulin, blood urea nitrogen, and glucose, and the activities of aspartate aminotransferase (AST) and g-glutamyl transpeptidase (GGT) increased significantly compared with those in controls. In contrast, serum concentrations of albumin, calcium, and magnesium, and the activity of alkaline phosphatase (ALP) decreased significantly compared with those of healthy animals. The activities of ALP, AST, GGT, and creatine kinase and the concentration of phosphorus were higher in thoracic fluid than the serum values in the diseased group.

Conclusion:

When compared with the healthy controls, goats with CCPP have metabolic acidosis. Compared with the levels in healthy goats, the blood PCO₂, PO₂, BE, HCO₃, TCO₂, and SO₂ are low in goats with CCPP; however, the AnGap is higher in diseased goats.

Critical Systematic Review of Zoonoses and Transboundary Animal Diseases' Prioritization in Africa

Background: Disease prioritization aims to enhance resource use efficiency concerning human and animal health systems’ preparedness and response to the most important problems for the optimization of beneficial outcomes. In sub-Sahara Africa (SSA), several prioritizations of zoonoses and transboundary animal diseases (TADs) have been implemented at different scales to characterize potential disease impacts. Method and principal findings: In this systematic review, we analyze the methodologies used, outcomes, and their relevance by discussing criteria required to align decision-makers’ perceptions of impacts to those of other stakeholders for different prioritization in SSA. In general, the sectorial representativeness of stakeholders for processes implemented with the support of international partners showed slight differences with the absence of local stakeholders. Whatever the tool prioritized, zoonoses were similar in general because of the structured nature of those tools in assessing decision-makers’ preferences through value trade-offs between criteria while ensuring transparency and reproducibility. However, by involving field practitioners and farmers, there were different outcomes with processes concerning only decision makers and experts who were more sensitive to infectious TADs, while the former raised parasitic disease constraints. In this context, multicriteria decision analysis-based zoonoses and TADs prioritizations involving a balanced participation of stakeholders might contribute to bridging these divergences, whatever the scale. Conclusion and significance: Prioritization processes were important steps toward building and harmonizing technical laboratory and surveillance networks to coordinate projects to address priority zoonoses and TADs at the country and/or sub-regional level. Those processes should be enhanced.

Determination of Seroprevalence of Contagious Caprine Pleuropneumonia and Associated Risk Factors in Goats and Sheep Using Classification and Regression Tree

Simple Summary

The seroprevalence of contagious caprine pleuropneumonia in goats and sheep was determined and the associated risk factors were identified using the Classification and Regression Tree (CART) data mining model. The disease is more prevalent in older animals raised in a flock size ≥200 and that have communal feeding and watering. The CART model showed that the flock size >100 animals is the most important risk factor (importance score = 8.9), followed by age >4 y (5.3) and communal feeding and watering (3.1). The CART model showed more accuracy (area under the curve, AUC = 0.92 than the traditional logistic regression (AUC = 0.89).

Abstract

Classification and Regression Tree (CART) analysis is a potentially powerful tool for identifying risk factors associated with contagious caprine pleuropneumonia (CCPP) and the important interactions between them. Our objective was therefore to determine the seroprevalence and identify the risk factors associated with CCPP using CART data mining modeling in the most densely sheep- and goat-populated governorates. A cross-sectional study was conducted on 620 animals (390 sheep, 230 goats) distributed over four governorates in the Nile Delta of Egypt in 2019. The randomly selected sheep and goats from different geographical study areas were serologically tested for CCPP, and the animals’ information was obtained from flock men and farm owners. Six variables (geographic location, species, flock size, age, gender, and communal feeding and watering) were used for risk analysis. Multiple stepwise logistic regression and CART modeling were used for data analysis. A total of 124 (20%) serum samples were serologically positive for CCPP. The highest prevalence of CCPP was between aged animals (>4 y; 48.7%) raised in a flock size ≥200 (100%) having communal feeding and watering (28.2%). Based on logistic regression modeling (area under the curve, AUC = 0.89; 95% CI 0.86 to 0.91), communal feeding and watering showed the highest prevalence odds ratios (POR) of CCPP (POR = 3.7, 95% CI 1.9 to 7.3), followed by age (POR = 2.1, 95% CI 1.6 to 2.8) and flock size (POR = 1.1, 95% CI 1.0 to 1.2). However, higher-accuracy CART modeling (AUC = 0.92, 95% CI 0.90 to 0.95) showed that a flock size >100 animals is the most important risk factor (importance score = 8.9), followed by age >4 y (5.3) followed by communal feeding and watering (3.1). Our results strongly suggest that the CCPP is most likely to be found in animals raised in a flock size >100 animals and with age >4 y having communal feeding and watering. Additionally, sheep seem to have an important role in the CCPP epidemiology. The CART data mining modeling showed better accuracy than the traditional logistic regression.

Prioritizing smallholder animal health needs in East Africa, West Africa, and South Asia using three approaches: Literature review, expert workshops, and practitioner surveys

Managing the health needs of livestock contributes to reducing poverty and improving the livelihoods of smallholder and pastoralist livestock keepers globally. Animal health practitioners, producers, policymakers, and researchers all must prioritize how to mobilize limited resources. This study employed three approaches to prioritize animal health needs in East and West Africa and South Asia to identify diseases and syndromes that impact livestock keepers. The approaches were a) systematic literature review, b) a series of expert workshops, and c) a practitioner survey of veterinarians and para-veterinary professionals. The top constraints that emerged from all three approaches include endo/ ectoparasites, foot and mouth disease, brucellosis, peste des petits ruminants, Newcastle disease, and avian influenza. Expert workshops additionally identified contagious caprine pleuropneumonia, contagious bovine pleuropneumonia, mastitis, and reproductive disorders as constraints not emphasized in the literature review. Practitioner survey results additionally identified nutrition as a constraint for smallholder dairy and pastoralist small ruminant production. Experts attending the workshops agreed most constraints can be managed using existing veterinary technologies and best husbandry practices, which supports a shift away from focusing on individual diseases and new technologies towards addressing systemic challenges that limit access to veterinary services and inputs. Few research studies focused on incidence/ prevalence of disease and impact, suggesting better incorporation of socio-economic impact measures in future research would better represent the interests of livestock keepers.

Infection strategies of mycoplasmas: Unraveling the panoply of virulence factors

Mycoplasmas, the smallest bacteria lacking a cell wall, can cause various diseases in both humans and animals. Mycoplasmas harbor a variety of virulence factors that enable them to overcome numerous barriers of entry into the host; using accessory proteins, mycoplasma adhesins can bind to the receptors or extracellular matrix of the host cell. Although the host immune system can eradicate the invading mycoplasma in most cases, a few sagacious mycoplasmas employ a series of invasion and immune escape strategies to ensure their continued survival within their hosts. For instance, capsular polysaccharides are crucial for anti-phagocytosis and immunomodulation. Invasive enzymes degrade reactive oxygen species, neutrophil extracellular traps, and immunoglobulins. Biofilm formation is important for establishing a persistent infection. During proliferation, successfully surviving mycoplasmas generate numerous metabolites, including hydrogen peroxide, ammonia and hydrogen sulfide; or secrete various exotoxins, such as community-acquired respiratory distress syndrome toxin, and hemolysins; and express various pathogenic enzymes, all of which have potent toxic effects on host cells. Furthermore, some inherent components of mycoplasmas, such as lipids, membrane lipoproteins, and even mycoplasma-generated superantigens, can exert a significant pathogenic impact on the host cells or the immune system. In this review, we describe the proposed virulence factors in the toolkit of notorious mycoplasmas to better understand the pathogenic features of these bacteria, along with their pathogenic mechanisms.

"FastCheckFLI PPR-like"-A Molecular Tool for the Fast Genome Detection of PPRV and Differential Diagnostic Pathogens

To assist the global eradication of peste des petits ruminants virus (PPRV), a molecular test for the rapid and reliable detection of PPRV was developed which additionally enables the detection of pathogens relevant for differential diagnostics. For this purpose, the necessary time frame of a magnetic bead-based nucleic acid extraction protocol was markedly shortened to 7 min and 13 s. The optimized extraction was run on a BioSprint 15 platform. Furthermore, a high-speed multi-well RT-qPCR for the genome detection of PPRV and additional important pathogens such as Foot-and-mouth disease virus, Parapoxvirus ovis, Goatpox virus, and Mycoplasma capricolum subsp. capripneumoniae was established and combined with suitable internal control assays. The here-described qPCR is based on a lyophilized master mix and takes only around 30 to 40 min. Several qPCR cyclers were evaluated regarding their suitability for fast-cycling approaches and for their diagnostic performance in a high-speed RT-qPCR. The final evaluation was conducted on the BioRad CFX96 and also on a portable Liberty16 qPCR cycler. The new molecular test designated as "FastCheck^FLI PPR-like", which is based on rapid nucleic acid extraction and high-speed RT-qPCR, delivered reliable results in less than one hour, allowing its use also in a pen-side scenario.

Contagious caprine pleuropneumonia (CCPP): A systematic review and meta-analysis of the prevalence in sheep and goats

Contagious caprine pleuropneumonia (CCPP) is a highly contagious respiratory disease of small ruminants that is caused by the bacterium Mycoplasma capricolum subsp. capripneumoniae. Sheep and goats are two of the species of small ruminants most at risk of CCPP. Outbreaks of CCPP cause significant economic and trade disturbances in several parts of the world. However, the extent and magnitude of CCPP in a particular geographical region is still not well known due to lack of comprehensive data on its occurrence. The present study aimed to investigate the prevalence of CCPP in sheep and goats raised in different geographical regions as well as the factors contributing to the spread of the disease. Searches were done in five online repositories: PubMed, Web of Science, Scopus, CAB Direct and Google Scholar using pre-selected key terms. Data were retrieved from the 41 articles that met the study's inclusion criteria. The pooled prevalences were determined using a random effect meta-analysis model. Prevalence of CCPP was 23.19% (95% CI: 11.90-34.47%) in sheep and 24.91% (95% CI: 20.99-28.84%) in goats. Overall, the regional level pooled prevalence estimates ranged from 8.0% (95% CI: 6.91-9.09%) to 28.70% (22.02-35.38%), depending on species and world region. Substantial heterogeneity (I²  > 75%) was observed in most pooled prevalence estimates. The results indicate high prevalences of CCPP in sheep and goats across the regions, particularly in Africa and Asia, and highlights the need to institute appropriate control measures. Active surveillance and research on risk factors are recommended.

Using local knowledge in emerging infectious disease research

Emerging infectious diseases (EIDs) are a growing global health threat. The Stockholm Paradigm suggests that their toll will grow tragically in the face of climate change, in particular. The best research protocol for predicting and preventing infectious disease emergence states that an urgent search must commence to identify unknown human and animal pathogens. This short communication proposes that the ethnobiological knowledge of indigenous and impoverished communities can be a source of information about some of those unknown pathogens. I present the ecological and anthropological theory behind this proposal, followed by a few case studies that serve as a limited proof of concept. This paper also serves as a call to action for the medical anthropology community. It gives a brief primer on the EID crisis and how anthropology research may be vital to limiting its havoc on global health. Local knowledge is not likely to play a major role in EID research initiatives, but the incorporation of an awareness of EIDs into standard medical anthropological practice would have myriad other benefits.

Persistence in Livestock Mycoplasmas—a Key Role in Infection and Pathogenesis

Purpose of Review

Mycoplasma, economically important pathogens in livestock, often establishes immunologically complex persistent infections that drive their pathogenesis and complicate prophylaxis and therapy of the caused diseases. In this review, we summarize some of the recent findings concerning cellular and molecular persistence mechanisms related to the pathogenesis of mycoplasma infections in livestock.

Recent Findings

Data from recent studies prove several mechanisms including intracellular lifestyle, immune dysregulation, and autoimmunity as well as microcolony and biofilm formation and apoptosis of different host cell types as important persistence mechanisms in several clinically significant Mycoplasma species, i.e., M. bovis, M. gallisepticum, M. hyopneumoniae, and M. suis.

Summary

Evasion of the immune system and the establishment of persistent infections are key features in the pathogenesis of livestock mycoplasmas. In-depth knowledge of the underlying mechanisms will provide the basis for the development of therapy and prophylaxis strategies against mycoplasma infections.

Interleukin-17 mediates lung injury by promoting neutrophil accumulation during the development of contagious caprine pleuropneumonia

Contagious caprine pleuropneumonia (CCPP) is a highly contagious infectious disease of goats caused by Mycoplasma capricolum subspecies capripneumoniae (Mccp). CCPP outbreaks usually result in high morbidity and mortality of the affected goats, making this disease a major cause of economic losses to goat producers globally. However, the pathogenesis of CCPP remains unclear. Here, we show that IL-17-driven neutrophil accumulation is involved in the lung damage in CCPP goats. During CCPP development, intense inflammatory infiltrates could be observed in the injured lungs. Specifically, neutrophils were observed to be present within the alveoli. Increased IL-17 release drove the excessive influx of neutrophils into the lung, as IL-17 effectively stimulated the production of neutrophil chemoattractants from lung epithelial cells following Mccp infection. Our data highlight a critical role of IL-17-driven neutrophil accumulation in the pathogenesis of CCPP and suggest that IL-17 may potentially be a useful immunotherapeutic target for the treatment of CCPP.

The first identification of contagious caprine pleuropneumonia (CCPP) in sheep and goats in Egypt: molecular and pathological characterization

Contagious caprine pleuropneumonia (CCPP) is one of the most fatal and contagious diseases of goats. To date, the occurrence of CCPP in Egypt has not been reported. During the period from 2017 to 2018, 200 goats and 400 sheep from Matrouh Governorate (Al Alamein and El Hammam cities) were suspected to have CCPP; animals were examined to confirm the presence of CCPP infection as well as the epidemiological status, clinical features, and molecular and histopathologic characteristics of lung tissues. Additionally, a treatment trial was performed to assess the efficacy of anti-mycoplasma therapy in the treatment of clinical cases of this disease. The occurrence of CCPP was 32.5% and 5% in goats and sheep, respectively, while case fatality was 30% and 8% in goats and sheep, respectively. The clinical forms of CCPP in both sheep and goats varied from per-acute to acute or chronic cases. Histopathological analysis of lung tissues from dead cases (either sheep or goats) revealed different stages of broncho- and pleuropneumonia ranging from per-acute to acute or chronic stages. Lung tissues showed severe congestion of interalveolar capillaries, flooding of alveoli and bronchi with a fibrinous exudate, a high degree of pleural thickening, and multifocal areas of necrosis that were sometimes sequestered in the fibrous capsule. Isolation of Mycoplasma capricolum subspecies capripneumoniae (Mccp) was confirmed in all dead cases by agar and broth culture methods and polymerase chain reaction. The treatment trial revealed that the marbofloxacin and spiramycin groups had a higher cure rate (70%) than the oxytetracycline group (40%) and a lower fatality rate (30%) than the oxytetracycline group (60%). Conclusively, infection with CCPP in goats and sheep is considered to be novel for Mccp in Egypt, where this species is considered to be the main pathogen in goats, not in sheep. Additionally, it could be concluded that treatment may be effective only if given early. Further comprehensive surveys are required to investigate the risk of CCPP in goats and sheep in all Egyptian governorates.

Development and Evaluation of Epitope-Blocking ELISA for Detection of Antibodies against Contagious Caprine Pleuropneumonia in Goat Sera

Enzyme linked immunosorbent assays (ELISAs) have been developed for the detection of antibodies against contagious caprine pleuropneumonia (CCPP), the causative agent of which is Mycoplasma capricolum subsp. Capripneumoniae (Mccp). The currently available commercial CCPP competitive ELISA (CCPP cELISA) kit produced and supplied by IDEXX Company (Westbrook, Maine, United States) is relatively expensive for most African laboratories. To address this issue and provide a variety of choices, a sensitive and specific blocking-ELISA (b-ELISA) test to detect antibodies against CCPP was developed. We describe the newly developed CCPP blocking-ELISA based on the blocking of an epitope of a monoclonal antibody (Mccp-25) by a positive serum sample against the Mccp protein coated on a plate. The Percentage Inhibition (PI) cut-off value for the CCPP b-ELISA was set at 50 using 466 CCPP negative and 84 CCPP positive small ruminant sera. Of the negative sera, 307 were obtained from the Botswana National Veterinary Laboratory (BNVL) and 159 from the Friedrich-Loeffler-Institute (FLI) Germany. The 84 positive sera samples came from experimentally vaccinated goats at the AU-PANVAC facility in Debre-Zeit, Ethiopia. The relative diagnostic sensitivity and specificity of the CCPP b-ELISA was 93% and 88%, respectively. This test result indicated good correlation with that of the commercial CCPP cELISA by IDEXX Company (Westbrook, Maine, United States) with a Cohen's κ agreement of κ agreement of 0.85. The newly developed CCPP b-ELISA will be useful in the detection of antibodies for the diagnosis CCPP and for sero-surveillance during vaccination campaigns.

Novel Candidates for Vaccine Development Against Mycoplasma Capricolum Subspecies Capripneumoniae (Mccp)-Current Knowledge and Future Prospects

Exploration of novel candidates for vaccine development against Mycoplasma capricolum subspecies capripneumoniae (Mccp), the causative agent of contagious caprine pleuropneumonia (CCPP), has recently gained immense importance due to both the increased number of outbreaks and the alarming risk of transboundary spread of disease. Treatment by antibiotics as the only therapeutic strategy is not a viable option due to pathogen persistence, economic issues, and concerns of antibiotic resistance. Therefore, prophylactics or vaccines are becoming important under the current scenario. For quite some time inactivated, killed, or attenuated vaccines proved to be beneficial and provided good immunity up to a year. However, their adverse effects and requirement for larger doses led to the need for production of large quantities of Mccp. This is challenging because the required culture medium is costly and Mycoplasma growth is fastidious and slow. Furthermore, quality control is always an issue with such vaccines. Currently, novel candidate antigens including capsular polysaccharides (CPS), proteins, enzymes, and genes are being evaluated for potential use as vaccines. These have shown potential immunogenicity with promising results in eliciting protective immune responses. Being easy to produce, specific, effective and free from side effects, these novel vaccine candidates can revolutionize vaccination against CCPP. Use of novel proteomic approaches, including sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), two-dimensional gel electrophoresis, immunoblotting, matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF) mass spectrometry, tandem mass spectroscopy, fast protein liquid chromatography (FPLC), bioinformatics, computerized simulation and genomic approaches, including multilocus sequence analysis, next-generation sequencing, basic local alignment search tool (BLAST), gene expression, and recombinant expression, will further enable recognition of ideal antigenic proteins and virulence genes with vaccination potential.

Comparative evaluation of different therapeutic protocols for contagious caprine pleuropneumonia in Himalayan Pashmina goats

Therapeutic management of contagious caprine pleuroneumonia (CCPP) involves mostly the use of oxytetracycline followed by enrofloxacin and rarely tylosin. In many parts of the world including India, the former antibiotics are commonly available than the latter. Therefore, prolonged use of the same leads to the development of antibiotic resistance and decreased efficacy of drug. Besides, inflammatory and allergic pathogenesis of CCPP envisages combination therapy. In this study, we evaluated the effectiveness of the combination therapy using different antibiotics (oxytetracycyline @ 10: group I, enrofloxacin @ 5 group II, and tylosin: group III, @ 10 mg/kg body weight), along with anti-inflammatory (meloxicam @ 0.5 mg/kg) and anti-allergic (pheneramine maleate @ 1.0 mg/kg) drugs. These drugs were given intramuscularly at the interval of 48 h for four times in three test groups (n = 10) of Pashmina goats, viz. groups I, II, and III, respectively, affected with CCPP. Group IV (n = 10) was kept as healthy control when group V (n = 10) treated with oxytetracycline @ 10 mg/kg alone was used as positive control. Clinical signs, clinical parameters, pro-inflammatory cytokine (tumor necrosis factor alpha (TNF-α)), and oxidative stress indices (total oxidant status (TOS), total antioxidant status (TAS)) were evaluated at hours 0, 48, 96, and 144 of experimental trial. Tylosin-based combination therapy resulted in a rapid and favorable recovery resulting in restoration of normal body temperature (102.46 ± 0.31 °F), respiration rate (16.30 ± 0.79 per minute), and heart rate (89.50 ± 2.63 per minute) compared to the oxytetracycline (102.95 ± 0.13, 21.30 ± 1.12, 86.00 ± 2.33, respectively) and enrofloxacin (102.97 ± 0.19, 21.00 ± 1.25, 90.00 ± 2.58, respectively) treated groups. By hour 144, all the groups showed restoration of clinical parameters of normal health and diminishing signs of CCPP, viz. fever, dyspnea, coughing, nasal discharge, weakness, and pleurodynia. Significant (P ≤ 0.05) decrease in levels of TNF-α and non-significant (P > 0.05) decrease in levels of TOS and an increase in levels of TAS were noted from hour 0 to 144 in all the test groups. Within the groups, no significant (P > 0.05) change was noted in TNF-α, TOS, and TAS levels; however, TNF-α levels were comparatively lower in group III. Hematological parameters did not differ significantly (P > 0.05). From these findings, it can be inferred that tylosin-based combination therapy is relatively better for early, rapid, and safe recovery besides minimizing inflammatory and oxidative cascade in CCPP affected Pashmina goats compared to oxytetracycline- and enrofloxacin-based therapies.