Genotyping of Mycoplasma mycoides subsp. mycoides SC by multilocus sequence analysis allows molecular epidemiology of contagious bovine pleuropneumonia

Mycoplasma mycoides subsp. mycoides SC (MmmSC) is the etiological agent of contagious bovine pleuropneumonia (CBPP). Although eradicated in most developed countries, the disease reappeared in Europe in the 1990s. This reappearance may have been caused either by importation from sub-Saharan Africa, where CBPP is still endemic, or by the reemergence of virulent strains in Europe, as suggested by earlier studies. A multilocus sequence analysis scheme has been developed to address this issue and, most importantly, to be able to monitor new epidemics. The alignment of the full genome sequence of the reference strain PG1 and the partial genome sequence of a pathogenic strain allowed the identification of polymorphic sites. Nineteen initial loci were selected within housekeeping genes, genes of unknown function and non coding sequences. The suitability of these loci for genotyping MmmSC strains was first tested on six strains of diverse geographic origin. The analyses showed that the published PG1 sequence contained a number of specific polymorphisms that were therefore of no use for molecular typing. Among the eight informative polymorphic loci finally selected, only one (ftsY) was positioned within a housekeeping gene. Three main groups and 31 different allelic profiles were identified among 51 strains and strain variants examined. Cluster analysis confirmed that European strains from the 1990s did not originate from Africa. It also showed a genetic link between a European strain isolated in 1967 and those found in southern Africa and Australia. This was in agreement with historical data showing that CBPP was introduced in these regions during colonisation in the 19th century.     

Anthrax: a malady of animals and of man which hides in the earth

Anthrax is an infectious disease of herbivores, especially sheep and cattle, but also of horses, of pigs, of dogs, of wild animals and of humans. Bacillus anthracis causes the disease. This bacterium needs plenty of oxygen to procreate and to produce resistant spores, which remains viable in the soil during 3.5 years, at times during 15-20 years. The author tries to follow step by step the evolution of the ideas concerning the origin and the pathology as well as of the veterinarians measures against this disease during the 19th and 20th centuries. Many studies of the endemic anthrax were made from the beginning of the second half of the 19th century. Thanks to Louis Pasteur (1822-1895) in France and Robert Koch (1843-1910) in Germany, the anthrax could be identified with a soil-disease between 1870 and 1880. The statistics concerning the anthrax in the Grand-Duchy of Luxembourg compared to the geological and pedological structures of the soil, have fully confirmed the scientific findings at the end of the 19th century. Nowadays the anthrax has disappeared from our landscape thanks to the preventive inoculation and to the industrial use of the animal cadavers.     

Contagious bovine pleuropneumonia--a nearly forgotten disease?

Contagious bovine pleuropneumonia (CBPP) caused by Mycoplasma mycoides subsp. mycoides small colony type (MmmSC) is a notifiable disease and has to be reported to the World Organisation for Animal Health (Office International des Epizooties, OIE, http://www.oie.int). Despite the fact that the last reported cases in Germany date back to 1926, the risk of introduction through clinically inconspicuous animals from countries where the disease is still endemic is rising. This is due mainly to an increase in international trade of live cattle and the failure to contain CBPP in many parts of Africa and elsewhere. To detect and eliminate this highly contagious infectious disease of the bovine respiratory tract, it is necessary to recognize matching clinical symptoms as soon as possible, as well as to have efficient methods for its detection on hand. In the present paper, we describe clinical manifestations and review state-of-the-art research, as well as currently used detection methods.     

Private sector involvement in the control of contagious bovine pleuropneumonia (CBPP) in the Kazungula district of Zambia benefitted the community and the control strategy

Contagious bovine pleuropneumonia (CBPP) is a disease of economic importance that is widely distributed in sub-Saharan African and contributes significantly to cattle morbidity and mortality. Lack of resources to implement eradication measures has led to the disease becoming endemic in most areas in sub-Saharan Africa where governments have little resources and the majority of the people are poor. Usually, control and eradication of such diseases as CBPP is treated as a public good by governments and to achieve this, governments are usually assisted by nongovernment organisations, bilateral government programmes and international donors. The private sector, which usually is companies that run businesses to make profit, although not very well established in sub-Saharan Africa could play a big role in the eradication of CBPP in the region. This could play a dual role of promoting investment and also eradicate livestock diseases which have proved a menace in the livestock sector. This paper highlights the role played by the private sector in the control of CBPP in Zambia.     

Development of an improved vaccine for contagious bovine pleuropneumonia: an African perspective on challenges and proposed actions

Contagious bovine pleuropneumonia (CBPP) caused by Mycoplasma mycoides subsp. mycoides (Mmm) is an economically very important cattle disease in sub-Saharan Africa. CBPP impacts animal health and poverty of livestock-dependent people through decreased animal productivity, reduced food supply, and the cost of control measures. CBPP is a barrier to trade in many African countries and this reduces the value of livestock and the income of many value chain stakeholders. The presence of CBPP also poses a constant threat to CBPP-free countries and creates costs in terms of the measures necessary to ensure the exclusion of disease. This opinion focuses on the biomedical research needed to foster the development of better control measures for CBPP. We suggest that different vaccine development approaches are followed in parallel. Basic immunology studies and systematic OMICs studies will be necessary in order to identify the protective arms of immunity and to shed more light on the pathogenicity mechanisms in CBPP. Moreover a robust challenge model and a close collaboration with African research units will be crucial to foster and implement a new vaccine for the progressive control of this cattle plague.     

Participatory appraisal of foot and mouth disease in the Afar pastoral area, northeast Ethiopia: implications for understanding disease ecology and control strategy

Foot and mouth disease (FMD) is the most economically important disease of livestock that still affects extensive areas of the world. This study described the use of participatory appraisal tools such as pair-wise ranking, matrix scoring and proportional piling to assess the perception of livestock keepers about the clinical signs and epidemiological features of cattle diseases with particular emphasis on FMD. Strong agreement among informant groups (W?=?0.710; P?=?0.000) in pair wise ranking indicated that the diseases were common problem to all the selected districts. Matrix scoring of disease indicators/signs also showed strong agreement (W?=?0.504 to 0.955; P?=?0.000) that implied significant current veterinary knowledge by Afar pastoralists. Age specific means of annual incidence rates estimated by proportional piling were significantly (P?<?0.05) different but negatively correlated for FMD, CBPP and pasteurellosis. However, correlation was not significant for anthrax, blackleg and other important diseases. Age specific means of annual mortality was significantly (P?<?0.05) but negatively correlated for FMD, CBPP, pasteurellosis and other important cattle diseases with correlation coefficients of ?0.72, ?0.81, ?0.8 and ?0.55, respectively. However, correlation (r?=?0.12) was not significant for anthrax and not correlated at all for blackleg. This study indicated that pastoralists have detailed knowledge about their livestock health problems, and hence the combined use of participatory appraisal and conventional methods is essential for an ultimate disease control strategy.     

Contagious bovine pleuropneumonia a review

Summary

The prevalence, characteristics of the aetiological agent, clinical signs, pathological changes, pathogenesis, epizootiology, microbiological and serological diagnosis, prevention, and control of contagious bovine pleuropneumonia (CBPP), caused by Mycoplasma mycoides subspecies mycoides SC type, are reviewed New aspects of the disease are discussed A renewed interest in this disease is important because of outbreaks in Southern Europe since 1980. When, at the end of 1992, the national borders of the countries of the European Community are abolished, it is conceivable that the disease will be introduced by cattle imported into CBPP‐free countries.     

Disease control during the colonial period in Australia

The first permanent European settlers of Australia arrived in 1788 to establish a penal colony at Sydney, New South Wales (NSW). As the colony grew and wool production increased, more free settlers and emancipists developed farming in inland Australia. During the 1840s veterinarians commenced arriving in small numbers but they were not closely associated with the development and execution of disease control programs, which was left to lay inspectors of stock. The arrival of William Tyson Kendall and coordinated action with Graham Mitchell led to the establishment of a private veterinary college following the passage of veterinary surgeons legislation in Victoria. From this time, veterinarians came to be appointed to positions formerly occupied by lay inspectors and the veterinary profession was able to take up the role of planning and executing government-led disease control programs. From a colony relying on wool for export to the UK, technical advancements in meat freezing and pasture improvement widened the range and increased the quantity of exported products. Before the advent of veterinary advances, sheep scab was eradicated, a vaccine was developed for anthrax and glanders infection of horses was prevented entry to Australia. Graduates from the Melbourne Veterinary College spread across Australia and in this period a conservative quarantine policy was developed following inaction to control an outbreak of contagious bovine pleuropneumonia (CBPP) and the escape of rabbits to form a plague across the continent. Coordinated control of CBPP had to await the next century and advancement of technology increased our understanding of bacteriology and immunity of infectious diseases. Veterinary services were provided to the militia sent by the colonies to the Boer Wars in South Africa 1987-1901 and the veterinarians from Victoria were led by an Australian trained veterinarian.     

Review of successes and failures of contagious bovine pleuropneumonia control strategies in Tanzania

Contagious bovine pleuropneumonia (CBPP) was first introduced in Tanzania in 1916 and was eradicated in 1964. The disease re-emerged in the country in 1990 and since then it has spread widely, threatening the entire national cattle herd. Because of lack of a clear disease-control policy, uncontrolled cattle movements, lack of public awareness and commitment, ineffective legislation, attempts to control and eradicate the disease for the last 10 years have failed. We reviewed the methods that were used to control CBPP in Tanzania during the 1916-1964 and 1990 episodes.     

Analyses of baseline surveillance data on contagious bovine pleuropneumonia in the southern Sudan

In the first survey for contagious bovine pleuropneumonia (CBPP) in the southern region of the Sudan (Bahr el Ghazal Province), 8.1% of Dinka-owned, and 9.2% of Fellata-owned, cattle, and 48 and 20% of their respective herds were serologically positive for CBPP. Dinka cattle between 3 months and 3 years of age had significantly higher test reaction rates than those younger or older. There was a positive association between reaction rates and herd size. A similar association was found between crude mortality rates and herd size, though virtually none of the variability among herds in crude mortality was accounted for by presence of CBPP infection. Overall, the study indicated a highly endemic situation for CBPP infection with rare overt disease under conditions of little prior intervention. Under such conditions, it is suggested that a “surveillance and selective actions” rather than a “mass actions” approach might be the most suitable, with vaccination limited by surveillance to those areas at highest risk of outbreaks of clinically important CBPP, namely areas of low herd immunity or those where actual outbreaks of clinical disease have already occurred. Such an approach to CBPP could serve as a “model” for establishing a system of improved disease intelligence overall in the southern Sudan.     

Challenges of controlling contagious bovine pleuropneumonia in sub-Saharan Africa

Contagious bovine pleuropneumonia (CBPP) is a disease of economic importance that is widely distributed in sub-Saharan African and contributes significantly to cattle morbidity and mortality. Control of CBPP offers a number of challenges as a result many developing countries in Africa are still struggling with this disease. In this study, we look at the challenges encountered in CBPP control in sub-Saharan Africa from the Zambian perspective. In conducting this study, we reviewed scientific literature and reports from the Ministry of Agriculture and Livestock and related animal institutions, and also made interviews with experts and key government officials involved in CBPP control in Zambia. Among the challenges identified for the successful control of CBPP were as follows: failure in the delivery of veterinary services, lack of a cattle identification system, natural phenomenon, livestock husbandry systems in the traditional sector, human movements, traditional practices among cattle farmers and cattle marketing systems. It was seen that the epidemiology of CBPP in Zambia is influenced by both ecological and anthological factors. Therefore, design and implementation of any control or eradication programme should be area/regional-dependent taking into account the different factors influencing disease transmission and maintenance.     

A model of contagious bovine pleuropneumonia transmission dynamics in East Africa

The dynamics of contagious bovine pleuropneumonia (CBPP) transmission vary widely between livestock production systems. This paper describes the development of a homogeneous, stochastic, compartmental model for CBPP transmission in pastoral herds of East Africa. The model was built using parameter estimates based on data published in the literature and on observations of livestock owners obtained through participatory research. The basic reproduction number for CBPP in southern Sudan was estimated to range from 3.2 to 4.6. The homogeneous model indicates that the critical community size for the persistence of CBPP falls within the typical herd sizes for pastoral communities in East Africa suggesting that individual isolated herds are capable of maintaining infection indefinitely. Vaccination alone with currently available vaccines was unlikely to eradicate the disease.     

Emerging therapeutic approaches for canine sarcomas: Pushing the boundaries beyond the conventional

Sarcomas represent a group of genomically chaotic, highly heterogenous tumours of mesenchymal origin with variable mutational load. Conventional therapy with surgery and radiation therapy is effective for managing small, low‐grade sarcomas and remains the standard therapeutic approach. For advanced, high‐grade, recurrent, or metastatic sarcomas, systemic chemotherapy provides minimal benefit, therefore, there is a drive to develop novel approaches. The discovery of “Coley's toxins” in the 19th century, and their use to stimulate the immune system supported the application of unconventional therapies for the treatment of sarcomas. While promising, this initial work was abandoned and treatment paradigm and disease course of sarcomas was largely unchanged for several decades. Exciting new therapies are currently changing treatment algorithms for advanced carcinomas and melanomas, and similar approaches are being applied to advance the field of sarcoma research. Recent discoveries in subtype‐specific cancer biology and the identification of distinct molecular targets have led to the development of promising targeted strategies with remarkable potential to change the landscape of sarcoma therapy in dogs. The purpose of this review article is to describe the current standard of care and limitations as well as emerging approaches for sarcoma therapy that span many of the most active paradigms in oncologic research, including immunotherapies, checkpoint inhibitors, and drugs capable of cellular metabolic reprogramming.     

Constraints to cattle production in a semiarid pastoral system in Kenya

Livestock keeping is the mainstay for the pastoral community while also providing social and cultural value. This study ranked main production constraints and cattle diseases that impacted livelihood and estimated herd prevalence, incidence rate, and impact of diseases on production parameters in a semiarid pastoral district of Narok in Kenya. Data collection employed participatory techniques including listing, pairwise ranking, disease incidence scoring, proportional piling, and disease impact matrix scoring and this was disaggregated by gender. Production constraints with high scores for impact on livelihood included scarcity of water (19 %), lack of extension services (15 %), presence of diseases (12 %), lack of market for cattle and their products (10 %), and recurrent cycle of drought (9 %). Diseases with high scores for impact on livelihood were East Coast fever (ECF) (22 %) and foot and mouth disease (FMD) (21 %). High estimated incidence rates were reported for FMD (67 %), trypanosomosis (28 %), and ECF (15 %), while contagious bovine pleuropneumonia (CBPP) had an incidence rate <1 %. Milk yield was affected by FMD, ECF, and trypanosomosis, while ECF was the cause of increased mortality. FMD, ECF, CBPP, and brucellosis caused increased abortion, while effect of gender and location of study was not significant. Despite CBPP being regarded as an important disease affecting cattle production in sub-Sahara Africa, its estimated incidence rate in herds was low. This study indicates what issues should be prioritized by livestock policy for pastoral areas.     

Within-herd spread of contagious bovine pleuropneumonia in Ethiopian highlands

Contagious bovine pleuropneumonia (CBPP) is a major threat for cattle health and production in Africa. This disease is caused by the small-colony type of Mycoplasma mycoides subspecies mycoides (MmmSC). Transmission occurs from direct and repeated contacts between sick and healthy animals. Veterinary services recently reported a resurgence of CBPP in the province of West Wellega, in the Ethiopian highlands. A research program was set up to estimate the epidemiological parameters of the within-herd infection spread. A follow-up survey was implemented in 71 sampled herds of the Boji district (West Wellega province). Fifteen herds were classified as newly infected and used in a serological- and clinical-incidence study. The overall 16-month cumulative sero-incidence risk was 34%. Clinical cases were recorded for 39% of the seropositive cattle; case-fatality risk was 13%. There was no evidence of benefit on infection spread of CBPP-control measures used locally by farmers (isolation or antibiotic treatments of sick animals). This might be related to a lack of power in the statistical analyses or to a quality problem for the medications used (and more generally, for health-care delivery in the Boji district).     

Prevalence of contagious bovine pleuropneumonia (CBPP) in northern Nigeria

An abattoir study on the prevalence of contagious bovine pleuropneumonia (CBPP) in five cattle-producing states of Nigeria from 1988 to 1997 was carried out. A total of 1,936,015 slaughtered cattle was examined for characteristic CBPP lung lesions. The overall lesion-based prevalence of CBPP was 0.29% (95% CI 0.24, 0.35). The prevalence varied significantly (P<0.05) by state but not across the years. A total of 279 CBPP outbreaks occurred and overall vaccination coverage was only 9.7%, both varied over the years and across the states. The reasons for inadequate vaccination coverage for CBPP as well as the need for re-establishment of a national CBPP control programme are suggested.     

Seroprevalence of contagious bovine pleuropneumonia at export quarantine centers in and around Adama,Ethiopia

A cross sectional study was undertaken from October 2010 to March 2011 to determine the seroprevalence of contagious bovine pleuropneumonia (CBPP) and its related risk factors in export quarantine centers. A total of 3,111 cattle sera were collected from different export quarantine farms located in and around Adama, namely, Bekero, Jogo, Kedir, and Dera farms, and tested for the presence of Mycoplasma mycoides subsp. mycoides small colonies antibody using competitive enzyme-linked immunosorbant assay. Of the total 3,111 cattle sera examined, 124 (4 %) were found positive for CBPP. Among the potential predisposing factors assessed, origin, transportation condition, confinement level, and stay time of the animals in quarantine center were not found significantly (P?>?0.05) associated with the occurrence of the disease. Whereas age was found significantly (P?<?0.05) associated with the occurrence of the disease in which a high seroprevalence was recorded in aged (9.5 %) animals than young (3 %). Generally, this study showed that CBPP is a threat for Ethiopian livestock export market and a well established disease in Borana and Bale areas, where the animals originated.     

The history of scabies in veterinary and human medicine from biblical to modern times

For many centuries a host of naturalists, savants, physicians and veterinarians have tried to unravel the etiology of scabies in humans and animals and to discover effective remedies to control it. After many attempts, success was achieved in the discovery of the parasitic etiology of the disease in the 15th century. Also, major advances with regard to the treatment of the disease were made during the 19th and 20th centuries. Today the prevalence of epidemic scabies in humans has diminished; on the other hand, good progress in the control of mange of livestock has been made only in a few countries including Australia, New Zealand and the U.S.A.     

Extended surveillance for CBPP in a free country: Challenges and solutions regarding the potential caprine reservoir

Contagious bovine pleuropneumonia (CBPP) is a severe respiratory disease of cattle and buffalo caused by Mycoplasma mycoides subsp. mycoides "Small Colony" (MmmSC). The agent of CBPP has been isolated from goats in different countries including CBPP-free areas. Goats can therefore be regarded as a putative MmmSC reservoir. No diagnostic test for CBPP surveillance in goats has been proposed as yet. Furthermore, serological tests could be seriously hampered by a widespread caprine infection due to the subspecies M. mycoides subsp. capri (Mmc), which is antigenically very close to MmmSC and displays high levels of genetic variability. A competition ELISA (cELISA) is currently used to screen for CBPP in cattle at the herd level in infected areas. The aim of this study was to see if the same cELISA would be specific enough to be used to screen goats despite the potential concomitant infection with Mmc. The cELISA titers of goats from Mmc-infected and non-infected herds were comparable and negative using the accepted cutoff for bovine sera. In contrast, seroconversion was observed in goats experimentally inoculated with an Mmc strain that cross-reacted with a monoclonal antibody targeting the same epitope as that used in cELISA. The probability of such false positivity occurring under field conditions is very low since Mmc strains with such an atypical antigenic profile emerge only rarely as a result of random nucleotide variation of the epitope-coding region. In conclusion, the commercially available cELISA can be considered specific enough to be used as a primary test to monitor passage of the CBPP agent in goats, but its sensitivity in goats requires further investigation.     

Indirect infection of cattle with contagious bovine pleuropneumonia.

Hay infected with Mycoplasma mycoides sub-species mycoides (M mycoides) was fed to six animals on three occasions. Five animals developed complement-fixing antibody in their sera and gave a positive reaction to the comparative intradermal allergic test. No animal died from contagious bovine pleuropneumonia (CBPP) but when they were killed, three had unequivocal lesions of the disease. M mycoides was isolated from the animals with these lesions but not from the others. CBPP was transmitted to two animals put in contact with those animals showing disease, and M mycoides was recovered from lesions in both animals. It is suggested that when unexplained outbreaks of CBPP occur, the possibility of indirect transmission should be considered.