Seroprevalence and associated risk factors of contagious caprine pleuropneumonia in selected districts of South Wollo Zone Northeast Ethiopia.

Contagious caprine pleuropneumonia (CCPP) is a severe and devastating respiratory disease of goats, which is characterized by severe serofibrinous pleuropneumonia accompanied by high morbidity and mortality. A cross-sectional study was conducted from July 2022 to January 2023 to determine the seroprevalence of CCPP and identify risk factors associated with the occurrence of CCPP in goats in five selected districts of the South Wollo Zone of the Eastern Amhara region. A total of 384 sera samples were collected from goats and examined for antibodies specific to Mycoplasma capricolum subspecies capripneumoniae (Mccp) using Competitive Enzyme-Linked ImmunoSorbent Assay (cELISA) test. Out of the total examined sera, 26 samples were positive for CCPP, giving an overall seroprevalence of 6.7% (95% CI = 6.64-9.77). A seroprevalence of 5.05%, 4.65%, 2.78%, 12.90%, and 10.77% were recorded in Ambasel, Tehuledere, Kalu, Dessie Zuria and Kutaber districts, respectively. However, there was no statistically significant difference among these five districts (p > 0.05). The seroprevalence of CCPP varies significantly between age groups and agroecology (p < 0.05). However, the seroprevalence did not vary with sex, body condition score (BCS), and flock size (p > 0.05). Old-aged goats (OR = 4.10) and goats found in the lowlands (OR = 5.09) were at higher risk of infection with CCPP than young-aged goats and goats found in the highlands, respectively. In conclusion, the present seroprevalence investigation indicated the occurrence of CCPP in those selected study districts of the South Wollo Zone. Therefore, appropriate control measures, including avoiding the mixing of flocks and vaccination should be designed and implemented especially in the lowland areas and older goats to reduce the further spread and magnitude of the disease.

Interactions between Mycoplasma mycoides subsp. mycoides and bovine macrophages under physiological conditions.

We investigated the interactions of unopsonized and opsonized Mycoplasma mycoides subsp. mycoides (Mmm) with bovine macrophages in vitro. Mmm survived and proliferated extracellularly on bovine macrophage cell layers in the absence of Mmm-specific antisera. Bovine complement used at non-bactericidal concentrations did neither have opsonizing effect nor promoted intracellular survival, whereas Mmm-specific antisera substantially increased phagocytosis and Mmm killing. A phagocytosis-independent uptake of Mmm by macrophages occurred at a high multiplicity of infection, also found to induce the production of TNF, and both responses were unaffected by non-bactericidal doses of bovine complement. Bovine complement used at higher doses killed Mmm in cell-free cultures and completely abrogated TNF responses by macrophages. These results provide a framework to identify Mmm antigens involved in interactions with macrophages and targeted by potentially protective antibodies and point towards a pivotal role of complement in the control of inflammatory responses in contagious bovine pleuropneumonia.

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.

Contagious Bovine Pleuropneumonia: Global Eradication Remains a Challenging and Distant Goal.

Contagious bovine pleuropneumonia (CBPP) is one of the six high impact diseases for which currently World Organization for Animal Health (WOAH) has established an official procedure for recognition of disease-free status for trade purposes. Although its exact distribution, incidence, and impact have not been well established, the disease is known to be endemic in sub-Saharan Africa, where it has a severe socio-economic impact on people's livelihoods. Control or elimination of the disease can be achieved by various strategies including vaccination, movement control, and stamping-out. Due to many factors, countries in sub-Saharan Africa are still struggling with this disease, compromising continental and global eradication. In this review, basic epidemiologic features and clinical signs of CBPP are presented and disease control challenges, particularly in endemic countries, are briefly discussed.

Seroprevalence of contagious bovine pleuropneumonia (CBPP) in cattle from Karamoja region, North-eastern Uganda.

BACKGROUND: Contagious bovine pleuropneumonia [CBPP] is a transboundary animal disease of cattle caused by Mycoplasma mycoides subsp. mycoides [Mmm]. CBPP causes severe economic losses to livestock producers in sub-Saharan Africa mainly due to high mortality, morbidity, reduction in productivity as well as livestock trade restrictions. This study aimed at determining seroprevalence of Mmm in cattle from Karamoja region, north-eastern Uganda; data that are required to design and implement risk based CBPP control program. METHODS: We randomly collected blood samples from 2,300 cattle spread across Karamoja region. Serum was extracted and screened for antibodies against Mycoplasma mycoides subsp. mycoides [Mmm] using the competitive enzyme linked immunosorbent assay [cELISA]. RESULTS: A quarter [25.4%; 95% CI: 23.7-27.3] of the screened cattle [n = 2,300] were sero-positive for Mmm. Amudat and Kaabong districts recorded the lowest [12.3%] and highest [30.7%] Mmm seroprevalence respectively. Increasing age, overnight stay in cattle kraals and location [certain districts, villages, herds and sub counties] of the cattle herds, the factors that promote animal commingling, were the most significant risk factors of seroconversion with Mmm. CONCLUSION: Results from this study indicated a higher seroprevalence of Mmm in Karamoja region cattle herds. This could be due to the increased frequency of CBPP outbreaks in recent years. To be effective, CBPP vaccination programs should target high risk herds along the international borders and other hotspot areas [e.g., parishes or sub counties] where cattle commingling is high.

Deep sequencing and variant frequency analysis for the quality control of a live bacterial vaccine against contagious bovine pleuropneumonia, strain T1.

Vaccination is the most cost-effective tool to control contagious bovine pleuropneumonia. The vaccines currently used in Africa are derived from a live strain called T1, which was attenuated by passage in embryonated eggs and broth culture. The number of passages is directly correlated to the degree of attenuation of the vaccinal strains and inversely correlated to their immunogenicity in cattle. Current quality control protocols applied to vaccine batches allow the assessment of identity, purity, and titers, but cannot assess the level of genetic drift form the parental vaccine strains. Deep sequencing was used to assess the genetic drift generated over controlled in vitro passages of the parental strain, as well as on commercial vaccine batches. Signatures of cloning procedures were detected in some batches, which imply a deviation from the standard production protocol. Deep sequencing is proposed as a new tool for the identity and stability control of T1 vaccines.

Hyper-production of porcine contagious pleuropneumonia subunit vaccine proteins in Escherichia coli by developing a bicistronic T7 expression system.

The ApxII toxin and the outer membrane lipoprotein (Oml) of Actinobacillus pleuropneumoniae are important vaccine antigens against porcine contagious pleuropneumonia (PCP), a prevalent infectious disease affecting the swine industry worldwide. Previous studies have reported the recombinant expression of ApxII and Oml in Escherichia coli; however, their yields were not satisfactory. Here, we aimed to enhance the production of ApxII and Oml by constructing a bicistronic expression system based on the widely used T7 promoter. To create efficient T7 bicistronic expression cassettes, 16 different fore-cistron sequences were introduced downstream of the T7 promoter. The expression of three vaccine antigens Oml1, Oml7, and ApxII in the four strongest bicistronic vectors were enhanced compared to the monocistronic control. Further optimization of the fermentation conditions in micro-well plates (MWP) led to improved production. Finally, the production yields reached unprecedented levels of 2.43 g L-1 of Oml1, 2.59 g L-1 of Oml7, and 1.21 g L-1 of ApxII, in a 5 L bioreactor. These three antigens also demonstrated well-protective immunity against A. pleuropneumoniae infection. In conclusion, this study establishes an efficient bicistronic T7 expression system that can be used to express recombinant proteins in E. coli and achieves the hyper-production of PCP vaccine proteins.

Mycoplasma mycoides subspecies capri, an uncommon mastitis and respiratory pathogen isolated in a German flock of goats.

Mycoplasma mycoides ssp. capri (Mmc) is one of the etiological microorganisms of contagious agalactia, which is among the diseases causing the highest economical losses in small ruminants. We report a disease outbreak in a German flock that led to significant suffering of goats characterized by mastitis, arthritis, pleuropneumonia and sudden deaths. Mmc was persistently isolated from many animals both from milk, and from a number of different swab and tissue samples. A number of closely related Mycoplasma spp. have to be taken into consideration to rule out important animal epizootics listed by European Animal Health Law and the World Organisation for Animal Health (WOAH). Some goats developed cross-reacting antibodies against Mycoplasma mycoides ssp. mycoides. Although Mmc is believed to be an uncommon microorganism in Germany, this study highlights that veterinarians should consider this pathogen in their work during herd health monitoring in Central Europe. Although eradication was not fully achieved, autogenous vaccination significantly seemed to improve animal health and welfare.

Sero-prevalence of contagious bovine pleuropneumonia in dryland of Borana, southern Oromia, Ethiopia.

Ethiopia is one of the largest African countries where livestock farming represent a relevant resource for the economy and the livelihood of the population. Contagious bovine pleuropneumonia (CBPP) is among the transboundaries animal disease that is hindering cattle farming in Ethiopia. Due to the limited resources of veterinary services, disease control and surveillance is discontinuous and occasional field investigations of target areas contribute to depict disease spreading in the country. The study was conducted to determine the seroprevalence, at herd and animal level, and identify the risk factors involved in CBPP diffusion and persistence in the Borana pastoral zone. A total of 498 serum samples were collected from 120 cattle herds and tested using competitive Enzyme-Linked Immunosorbent Assay (c-ELISA). Of 120 herds sampled, 37 (30.83%; (95% CI = 22.73-39.91%) were tested positive to CBPP antibody. Out of 498 sera samples tested 46 (9.24%; 95% CI = 6.84-12.13%) were positive. The highest prevalence was observed in Teltele (12/95; 12.90%; 95% CI = 6.7-21%) followed by Yabello (12/104; 11.54%; 95% CI = 6.1-19.3%) and Arero (10/91; 10.99%; 95% CI = 95% CI = 5.4-19.3%), whereas the lowest prevalence was observed in Gomole (5/101; 6.42%; 95% CI = 1.6-11.2%) and Dubluk (7/109; 4.95%; 95% CI = 2.6-12.8%) districts and statistically not significant (p > 0.05). Results of multivariate logistic regression analysis revealed that, age, herd movement and herd size of the animals had statistically significant effect on sero-positivity to CBPP (p < 0.05). Sex, season and body condition were not significantly (p > 0.05) associated with the occurrence of CBPP. The study confirms that CBPP is persistent in the territory and remain as a major problem that affects health and productivity of cattle. Therefore, awareness creation to the pastoralists in the study area about the effect of CBPP and designing appropriate control methods has a paramount importance to improve the health and productivity of cattle production in the area.

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.

Multi-locus sequence analysis reveals great genetic diversity among Mycoplasma capricolum subsp. capripneumoniae strains in Asia.

Multi-Locus Sequence Analysis (MLSA) of Mycoplasma capricolum subsp. capripneumoniae (Mccp) strains from Asia revealed unforeseen diversity and a central position for genotyping groups representing strains from Central/East Asia, suggesting a possible origin of contagious caprine pleuropneumonia in this continent. A better assessment of the emergence, diversity and distribution of Mccp in Asia and Africa calls for renewed efforts to dramatically enlarge the sample of strains. Availability and affordability in the field, added to superior typeability (directly from poor samples) and high stability, discriminatory power and concordance with epidemiological and phylogenetic analyses, make MLSA an excellent tool for such investigations.

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 and Evaluation of a Combined Contagious Bovine Pleuropneumonia (CBPP) and Lumpy Skin Disease (LSD) Live Vaccine.

Mycoplasma mycoides subsp. mycoides (Mmm) is the causative agent of contagious bovine pleuropneumonia (CBPP). Lumpy skin disease (LSD) is a viral disease of cattle caused by lumpy skin disease virus (LSDV). LSD and CBPP are both transboundary diseases spreading in the same areas of Africa and Asia. A combination vaccine to control CBPP and LSD offers significant value to small-scale livestock keepers as a single administration. Access to a bivalent vaccine may improve vaccination rates for both pathogens. In the present study, we evaluated the LSDV/CBPP live combined vaccine by testing the generation of virus neutralizing antibodies, immunogenicity, and safety on target species. In-vitro assessment of the Mycoplasma effect on LSDV growth in cell culture was evaluated by infectious virus titration and qPCR during 3 serial passages, whereas in-vivo interference was assessed through the antibody response to vaccination. This combined Mmm/LSDV vaccine could be used to protect cattle against both diseases with a single vaccination in the endemic countries. There were no adverse reactions detected in this study and inoculated cattle produced high levels of specific antibodies starting from day 7 post-vaccination, suggesting that this combination vaccine is both safe and effective.

Contagious bovine pleuropneumonia: Seroprevalence and its associated risk factors in selected districts of Afar region, Ethiopia.

BACKGROUND: In pastoral and lowland areas of the country particularly in Afar region, studies suggested higher prevalence of contagious bovine pleuropneumonia (CBPP) than mid and highland agro-ecologies. Though CBPP is a prime constraint to cattle productivity in the region, research outputs pertaining to CBPP are unavailable compared to highland areas. Thus, the objectives of the current study were to determine seroprevalence of CBPP and assess risk factors in selected districts of Afar region. METHODS: A cross-sectional study was conducted on cattle aged 6 months and above from February 2018 to January 2019 in selected districts of the region. A total of 420 blood samples were collected and sera were separated for further serologic analysis. Using competitive enzyme linked immunosorbent assay (c-ELISA), antibodies against Mycoplasma mycoides subspecies mycoides small colony (MmmSc) were detected at National Veterinary Institute, Ethiopia. Data were analysed using Stata version 14.0. RESULT: Of 420 samples tested by c-ELISA, 158 samples were found to be positive for CBPP providing an overall seroprevalence of 37.6%. Among the three risk factors considered (age, sex and district) assessed, only two (age and district) were found to be associated significantly with the disease (p < 0.05) at 95% CI and p-value less than 5% applying logistic regression. CONCLUSION: The study has revealed a higher prevalence of CBPP over the study areas urging a coordinated act to be set in place.

Rapid detection of Mycoplasma mycoides subsp. capri and Mycoplasma capricolum subsp. capripneumoniae using high-resolution melting curve analysis.

Mycoplasma capricolum subsp.subsp. capripneumonia (Mccp) and Mycoplasma mycoides subsp.sbusp. capri (Mmc) cause caprine pleuropneumonia (CCPP) and mycoplasmal pneumonia in goats and sheep (MPGS), respectively. These diseases cannot be identified on clinical symptoms alone and it is laborious to distinguish them using biochemical methods. It is therefore important to establish a simple, rapid identification method for Mccp and Mmc. Here, we report a high-resolution melting (HRM) curve analysis using specific primers based on the Mmc 95010 strain MLC_0560 and Mccp F38 strain MCCPF38_00984 gene sequences. The method was highly specific with intra- and inter-batch coefficients of variation < 1%. The lower limit of detection for Mccp and Mmc was 55 copies/µL and 58 copies/µL, respectively. HRM and fluorescence qPCR results were compared using 106 nasal swabs and 47 lung tissue samples from goats (HRM-qPCR coincidence rate 94.8%; 145/153). Mycoplasma isolation and identification was performed on 30 lung tissue samples and 16 nasal swabs (HRM-culturing coincidence rate 87.0%; 40/46). HRM analysis was more sensitive than fluorescence qPCR and Mycoplasma isolation, indicating the practicality of HRM for accurate and rapid identification of Mccp and Mmc, and diagnosis and epidemiology of CCPP and MPGS.

Isolation and identification of Mycoplasma mycoides subsp. mycoides in cattle from south-east Nigeria.

Background: Mycoplasma mycoides subsp. mycoides is the causative organism of Contagious Bovine Pleuropneumonia (CBPP). It is a trans-boundary disease and an endemic in Nigeria having caused serious financial loss for the country's economy. Aim: This study was undertaken to isolate and confirm the presence of M. mycoides subsp. mycoides (Mmm) in cattle, from three selected South-Eastern states of Nigeria. Method: A total of 90 bovine samples (25 pleural fluids and 65 lung tissues) suggestive of CBPP were collected from different abattoirs in the three selected South-eastern states of Nigeria (Anambra, Enugu, and Imo), for the isolation of Mmm by employing cultural method, whereas for confirmation polymerase chain reaction (PCR) approach was used. The collected samples were cultured on Pleuropneumonia like organism (PPLO) agar according to specific protocols. Results: Twenty five of the samples (lungs and pleural fluid) were positive for Mmm on PPLO agar giving an isolation rate of 27.7%. Only 21 of the isolates were further confirmed using PCR. The PCR amplification of the isolates produced a product of 1.1 kbp which is specific for Mmm. No positive isolates were recovered from Imo state. Conclusion: This study confirms the presence of Mmm as the causative organism of CBPP in Southeast Nigeria. It is recommended that active surveillance and vaccination protocol should be undertaken in the region for the control and prevention of this disease.

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.

[Present Situation of Contagious Bovine Pleuropneumonia in Central African Republic]. / Situation Actuelle de la Péripneumonie Contagieuse Bovine en République Centrafricaine.

Aims: The aim of this study was to analyse the current situation of Contagious Bovine Pleuropneumonia (CBPP) in the Central African Republic (CAR) by seroprevalence analysis, as well as isolation and characterization of strains of the etiologic agent, Mycoplasma mycoides mycoides (Mmm), circulating in livestock breeding regions. Material and methods: The strains obtained were subjected to whole genome sequencing by Illumina technology and genotyped using the eMLST technique based on 62 genes of the Mmm core genome. Their sensitivity to tetracycline was assessed by determination of the minimum inhibitory concentration (MIC) on agar. A seroprevalence analysis by competitive ELISA was conducted in livestock breeding regions (West, Centre and East CAR), including both zebu and taurine cattle breeds, and both males and females. Results: The three strains isolated in the three regions of the CAR shared exactly the same genomic sequence. Phylogenetic analysis showed that they were closely related to a strain isolated in the CAR in 1991, also sequenced in this study, and clustered with Mmm strains originating from East and Central Africa. The recent isolates presented increased MIC values, though they were still sensitive to tetracycline. The global CBPP prevalence in the CAR was estimated at 12.5% with no significant differences observed between cattle breeding regions, nor between males and females. However, a significantly higher prevalence was observed in zebu compared to taurine cattle, most likely in relation to their herding system based on cattle transhumance and nomadic pastoralism. Conclusion: CBPP is enzootic in the CAR in spite of control campaigns based on use of the live T1 vaccines, which have shown little efficacy due to poor implementation in the field. New strategies combining controlled use of antibiotics and inactivated vaccines, with increased thermostability, should be well received by livestock keepers and allow a better control of CBPP in the region. The fact that the recent Mmm isolates are still resistant to tetracycles is encouraging.

Seroprevalence and determinants of contagious bovine pleuropneumonia in cattle in Burkina Faso.

Contagious bovine pleuropneumonia (CBPP) is a bacterial disease caused by Mycoplasma mycoides subsp. Mycoides. This disease affects ruminants mainly cattle with respiratory disorders as predominant symptoms. In Burkina Faso, this condition has been considered as enzootic since several years but data on its seroprevalence remains scares. This study aimed to establish the serological prevalence and determinants of CBPP in Burkina Faso in 2017. For this purpose, 3969 serum samples have been collected following a stratified sampling plan based on vaccination coverage in 12 regions, 84 communes, and 210 villages and analyzed using c-ELISA test. Individual seroprevalence was 16.91% (95% CI: 15.74-18.07%), while 84.5% (95% CI: 60.46-80.02%) of communes, chosen as epidemiological units were found positive. The individual prevalence was found to be associated with agro-ecological area (p < 0.05) and a prevalence of 18.70% (95% CI: 16.74-20.66%) was noted in Sahelian areas, while 15.79% (95% CI: 14.34-17.23%) was found in Soudanian areas. The prevalence was also significantly associated with vaccination coverage (p < 0.05) with a prevalence of 13.92% (95% CI: 11.66-16.18%), 19.21% (95% CI: 16.66-20.75%) and 11.61%(95% CI: 9.00-14.23%) for high, moderate, and low vaccination coverage respectively. The individual prevalence was respectively 16.97 (95% CI: 15.56-18.39%) and 17.13% (95% CI: 15.93-18.33%) for female and animals more than 2 years old. According to regions, the highest seroprevalence was found in Plateau Central region (38.18%, 95% CI: 29.1-47.26%), while the lowest was found in Centre-Est Region (7%, 95% CI: 4.5-9.5%). These prevalence data will allow us to adapt the ongoing strategy to control CBPP in Burkina Faso.

Baseline analysis of Mycoplasma mycoides subsp. mycoides antigens as targets for a DIVA assay for use with a subunit vaccine for contagious bovine pleuropneumonia.

BACKGROUND: Mycoplasma mycoides subsp. mycoides (Mmm) is the causative agent of contagious bovine pleuropneumonia in cattle. A prototype subunit vaccine is being developed, however, there is currently no diagnostic test that can differentiate between infected cattle and those vaccinated with the prototype subunit vaccine. This study characterized Mmm proteins to identify potential antigens for use in differentiating infected from vaccinated animals. RESULTS: Ten Mmm antigens expressed as recombinant proteins were tested in an indirect ELISA using experimental sera from control groups, infected, and vaccinated animals. Data were imported into R software for analysis and drawing of the box and scatter plots while Cohen's Kappa assessed the level of agreement between the Mmm antigens. Two vaccine antigens (MSC_0499 and MSC_0776) were superior in detecting antibodies in sera of animals vaccinated with the subunit vaccines while two non-vaccine antigens (MSC_0636 and LppB) detected antibodies in sera of infected animals showing all clinical stages of the disease. Sensitivity and specificity of above 87.5% were achieved when the MSC_0499 and MSC_0636 antigens were tested on sera from vaccinated and infected animals. CONCLUSIONS: The MSC_0499 and MSC_0776 antigens were the most promising for detecting vaccinated animals, while MSC_0636 and LppB were the best targets to identify infected animals. Further testing of sera from vaccinated and infected animals collected at different time intervals in the field should help establish how useful a diagnostic test based on a cocktail of these proteins would be.