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A brief history of bovine tuberculosis (bTB) and its control in Great Britain (GB) is presented. Numerous diverse policies to control the disease in humans, cattle and wildlife have been pursued over the last 100 years and many millions of pounds have been spent. After notable success in reducing the incidence and prevalence of bTB in cattle in GB from the 1950s to the mid-1980s, the geographical spread of the disease and the number of cattle slaughtered have increased continually since that time, with a high point of bTB incidence in 2008. This increase appeared to coincide with changing policy regarding the control of the disease in badgers, with a more humane approach adopted and with strengthened protection for badgers through legislation. Indeed, there has been much controversy in the debate on the role of badgers in disease transmission to cattle and the need for their control as vectors of the disease. The issue has attracted the attention of the media and there have been various commissioned research projects, trials and public consultations. The findings of two social science investigations presented as examples showed that citizens generally believed that bTB in cattle is an important issue that needs to be tackled, but objected to badgers being killed, whilst cattle farmers were willing to pay around £17/animal/year for a bTB cattle vaccine. It is noted that successes regarding the control of bTB in other countries have combined both cattle and wildlife controls and involved industry working in close partnership with government.

Medical historians have recently become interested in the veterinary past, investigating the development of animal health in countries such as France, the Netherlands, the United Kingdom and the United States. An appreciation of the German context, however, is still lacking - a gap in the knowledge that the present article seeks to fill. Providing a critical interpretation of the evolution of the veterinary profession, this investigation explains why veterinary and medical spheres intersected, drifted apart, then came back together; it also accounts for the stark differences in the position of veterinarians in Germany and Britain. Emphasis is placed on how diverse traditions, interests and conceptualisations of animal health shaped the German veterinary profession, conditioned its field of operation, influenced its choice of animals and diseases, and dictated the speed of reform. Due to a state-oriented model of professionalisation, veterinarians became more enthusiastic about public service than private practice, perceiving themselves to be alongside doctors and scientists in status, rather than next to animal healers or manual labourers. Building on their expertise in epizootics, veterinarians became involved in zoonoses, following outbreaks of trichinosis. They achieved a dominant position in meat hygiene by refashioning abattoirs into sites for the construction of veterinary knowledge. Later, bovine tuberculosis helped veterinarians cement this position, successfully showcasing their expertise and contribution to society by saving as much meat as possible from diseased livestock. Ultimately, this article shows how veterinarians were heavily 'entangled' with the fields of medicine, food, agriculture and the military.

Despite many years of state-sponsored efforts to eradicate the disease from cattle through testing and slaughter, bovine tuberculosis (bTB) is still regarded as the most important and complex of animal health challenges facing the British livestock agricultural industry. This paper provides a historical analysis of the ongoing bTB statutory eradication programme in one part of the UK - Northern Ireland (NI) - which began in 1949 as a voluntary scheme, but between 1959 and 1960 became compulsory for all cattle herd-owners. Tracing bTB back through time sets the eradication efforts of the present day within a deeper context, and provides signposts for what developed in subsequent decades. The findings are based primarily on empirical research using historical published reports of the Ministry of Agriculture and state documents held in the public archives in NI, and they emphasize the need to consider the economic, social and political contexts of disease eradication efforts and their influences on both the past and the present.

Panama remains free of zoonotic tuberculosis caused by Mycobacterium bovis. However, DNA fingerprinting of 7 M. bovis isolates from a 2013 bovine tuberculosis outbreak indicated minimal homology with strains previously circulating in Panama. M. bovis dispersion into Panama highlights the need for enhanced genotype testing to track zoonotic infections.

We analyzed the most likely cause of 687 bovine tuberculosis (bTB) breakdowns detected in Spain between 2009 and 2011 (i.e., 22% of the total number of breakdowns detected during this period). Seven possible causes were considered: i) residual infection; ii) introduction of infected cattle from other herds; iii) sharing of pastures with infected herds; iv) contiguous spread from infected neighbor herds; v) presence of infected goats in the farm; vi) interaction with wildlife reservoirs and vii) contact with an infected human. For each possible cause a decision tree was developed and key questions were included in each of them. Answers to these key questions lead to different events within each decision tree. In order to assess the likelihood of occurrence of the different events a qualitative risk assessment approach was used. For this purpose, an expert opinion workshop was organized and ordinal values, ranging from 0 to 9 (i.e., null to very high likelihood of occurrence) were assigned. The analysis identified residual infection as the most frequent cause of bTB breakdowns (22.3%; 95%CI: 19.4-25.6), followed by interaction with wildlife reservoirs (13.1%; 95%CI: 10.8-15.8). The introduction of infected cattle, sharing of pastures and contiguous spread from infected neighbour herds were also identified as relevant causes. In 41.6% (95%CI: 38.0-45.4) of the breakdowns the origin of infection remained unknown. Veterinary officers conducting bTB breakdown investigations have to state their opinion about the possible cause of each breakdown. Comparison between the results of our analysis and the opinion from veterinary officers revealed a slight concordance. This slight agreement might reflect a lack of harmonized criteria to assess the most likely cause of bTB breakdowns as well as different perceptions about the importance of the possible causes. This is especially relevant in the case of the role of wildlife reservoirs.

The emergence of wildlife reservoirs of Mycobacterium bovis infection in cattle as well as increased inter-regional trade with associated spread of M. bovis has led to renewed interest in the use of vaccines for the control of bovine tuberculosis (TB). Field efficacy trials performed in the early 20th century demonstrated the partial effectiveness of bacilli Calmette-Guerin (BCG) for the control of bovine TB. Recent experimental trials with cattle have demonstrated that: (1) subunit vaccines may boost immunity elicited by BCG in cattle, (2) T cell central memory immune responses evoked by protective vaccines correlate with protection upon subsequent M. bovis challenge, (3) BCG is particularly protective when administered to neonates, and (4) differentiation of infected from vaccinated animals (DIVA) is feasible in cattle using in vitro or in vivo methods. In regards to wildlife reservoirs, the efficacy of BCG delivered orally has been demonstrated for brushtail possums (in field trials) as well as Eurasian badgers, wild boar, and white-tailed deer (each in experimental challenge studies). Vaccine delivery to wildlife reservoirs will primarily be oral, although a parenteral route is being deployed for badgers in England. Vaccine efficacy trials, both experimental challenge and field studies, with cattle and their wildlife reservoirs represent a primary example of the one health approach, with outcomes relevant for both veterinary and medical applications., (Published by Elsevier Ltd.)

Bovine tuberculosis is a dangerous mycobacterium that can be conveyed to humans in the meat and milk of cattle. By the mid-1800s, when health scientists began arguing about its zoonotic potential and danger to humans, the disease was well established in Australian cattle herds. This article examines the Queensland response to bovine tuberculosis from the late 1800s to the 1940s, when the problem of tubercular cattle could no longer be ignored. It shows that despite widespread concern about milk safety and increasing knowledge of the disease's aetiology, the Queensland government directed its milk safety activities towards public health education rather than the inadequacies of the dairy industry's approach to bovine tuberculosis. As such, it was tardy in addressing bovine tuberculosis.

As was the case with meat, the detection of the tuberculosis bacterium in cattle resulted in the attribution of an important role to milk in human tuberculosis infection. However, the case of milk had a more serious impact with graver consequences than did meat. In effect, milk was the principal foodstuff by means of which tuberculosis was passed from cattle to humans-indeed it could be said that it was the only effective vector that carried the bovine bacterium to the human organism. In light of this information, this article makes the case that milk acted as the most common means of transmission of bovine tuberculosis to humans, taking particular note of the problem of the hygienic milk supply in Spain.

If we consult current treatises that address tuberculosis infection by Mycobacterium bovis, we find that they neglect meat or accord it very little importance as a vector of transmission of tuberculosis to humans. However, several decades ago, the books of Veterinary Inspection concerning food dedicated numerous pages to tuberculosis in meat and the seizure of consumptive animals. The criteria or attitudes concerning meat from tuberculosis-infected animals have fluctuated over time, from rigorous extremes that, on one hand, required the seizure and destruction of the food products obtained from infected animals from a strictly hygienic measure, to other more practical considerations applying economic arguments, and which accepted the conditional use of these products due to the universal shortage of animal proteins. Consequently, the use or non-use of meat from animals infected with tuberculosis became one of the questions that prompted the greatest concern amongst researches and technicians. It is for these reasons that this paper addresses the history of meat as a vehicle of zoonotic transmission, highlighting its importance and repercussions on health inspections of meat in abattoirs.

Bovine tuberculosis is one of the most complex animal health problems that the farming industry in Great Britain faces today. In leading and facilitating the changes to policy required to reverse the long-term upward trend in the disease, Government is heavily reliant on evidence emerging from its wide-ranging bovine tuberculosis research programme. The paper outlines development of policy in Great Britain and its relationship to research findings.

Mycobacterium bovis and closely associated acid-fast bacilli cause disease in humans. Epidemiologic investigations reveal that the organism may be ingested or inhaled. Extra pulmonary lesions may occur associated to the consumption of infected milk, even though with the practice of boiling milk, and the growth of milk pasteurization plants all over the world, the digestive route of infection became less important. On the other hand, airborne infection continues to occur among meat industry and slaughterhouse workers, in regions where the infection is still prevalent in cattle. Evidence of person to person transmission is rare. Main causes of concern related to M. bovis in industrialized countries are: epizootics in domesticated and wild mammals and latent infection in immigrants. Although multidrug-resistant (MDR) strains of M. bovis have been identified, case reports reveal that anti-tuberculosis drugs routinely used to treat Mycobacterium tuberculosis-infected patients are effective when properly administered.

This paper analyzes the Winnipeg health department's campaign to eliminate tuberculosis in dairy herds supplying milk to the city. It examines the complexity of creating dairy policies at a time when there was no consensus about the role that Mycobacterium bovis played in the etiology of tuberculosis in humans, and when dairy producers and consumers often resisted regulations that increased their costs. The article argues that the scientific debates about the regulation of the city's milk supply enabled physicians and veterinarians to enlarge their professional practices; that the benefits and costs of the dairy policies were not equally distributed; and that Winnipeg's milk supply remained vulnerable to both deliberate and accidental contamination throughout this period.

Before World War I, British and American public health officials correlated tuberculosis in dairy cattle with severe infections in milk-drinking children. They traced bacteria in municipal milk supplies, mapped the locations of infected animals, and sought regulatory power to destroy them. Consumers, milk producers, municipal officials, veterinarians, and physicians all influenced the shape of antituberculosis regulations. Many condemned pasteurization as too costly and as masking tubercular contamination and poor sanitation. They saw milk-borne tuberculosis as an environmental as well as a bacteriological problem. Similar to other zoonotic diseases such as BSE, bovine tuberculosis blurred the boundaries between urban and rural, production and consumption, and human and animal bodies.

By the 1890s, questions about tuberculous meat in Britain served to transform the issue of infected meat from an ill-defined to a concrete threat. Veterinarians, building on European inoculation (or transmission) experiments, played a prominent part in constructing the debate, with medical officers of health following. With the emergence of bacteriology in the 1880s, a consensus emerged about the dangers of tuberculous meat: Robert Koch's identification of the tubercle bacillus in 1882, and the connection he saw between bovine tuberculosis and the disease in man, provided confirmation of the disease's danger to man. It was from this point that veterinary and public health interests diverged. Whereas a general agreement had been reached, the extent of the problem remained open to doubt. Confusion revolved around two issues: the localization of infection, and the question of cooking. The latter was thought to make tuberculous meat "safe," as attention shifted to the problem of milk; whereas the former frustrated efforts to combat the sale of meat showing signs of infection.

The intricate causal relationships between disease in man and disease in animals first began to be elucidated in the mid-19th century. Although the connections between animal and human disease are now generally understood, individuals as well as societies remain slow to act on this knowledge. This paper examines the gradual recognition of these disease connections and explores the parallel theme of man's reluctance to appreciate the implications of these connections. It identifies factors that have inhibited the realization of the links between disease in man and animals, and discusses several milestones in the scientific elucidation of these links. Beginning with emerging concerns over the relationship between bovine and human tuberculosis in the 1860s, it follows the discovery of insect vectors, animal reservoirs, and the links between animals, influenza, and man. Despite warnings of the potential significance for human disease of patterns of changes in the relationship with animals and the natural world, scientists have continued to treat human and animal health as largely independent disciplines, while historians too have neglected this important aspect of human disease.

Bovine tuberculosis is a highly prevalent animal disease in Argentina. In this work evidence was obtained showing that a major Mycobacterium bovis group in Argentina had been introduced with the bovine bulls imported from the United Kingdom at the end of the XIX century. This evidence came from two sources: historical, obtained by bibliographical references, and from laboratory results, using a molecular typing method called spoligotyping. These strains are also present in other countries that introduced cattle from the same origin.

The large declines in the incidence of tuberculosis over time in the industrially developed nations have usually been attributed to natural selection or to socio-economic improvements. Both explanations are beset with problems, as there is little firm evidence for the occurrence of natural selection of resistance to tuberculosis to any significant extent, and doubts have been expressed as to whether the incidence of a disease can be directly related to measures of socio-economic change without consideration of the impact of the many specific public health measures that have been taken. In addition, analyses of the changing prevalence of tuberculosis must consider the impact of changing environmental and ecological factors that affect, for example, the immunising effect of exposure to Mycobacterium bovis and saprophytic mycobacteria. It is also necessary to determine whether the causative organism is undergoing evolutionary change, as recent reports suggest.

In 1968 in the Czech republic the programme of elimination of tuberculosis in cattle caused by germs of Mycobacterium bovis was successfully completed. The project proper was started in 1959 by examination of the whole population of cattle with tuberculin tests. The situation which was revealed was disastrous: the prevalence in cattle was on average 21.03% whereby it reached 32.26% in milking cows, i.e. every third cow had TB, as was also confirmed in slaughterhouses. Hundreds of cases in humans caused by M. bovis were notified. The annual economic losses were more than a billion crowns. The health campaign was based on the method "test and slaughter" and on the replacement of heavily infected herds by TB free ones. It was necessary to replace 1,360,000 heads of TB cattle. This called for the solution of many complicated methodical, legislative, organizational, economic and social problems. Mandatory pasteurization of milk was introduced. Tuberculin tests of the whole cattle population (on average twice a year) supplemented by epizootological, laboratory and postmortem examinations led to the detection of all foci. The final results are up to the present time reflected in the substantially better production capacity of the cattle, TB free milk and a marked decline of M. bovis in humans.

A review of history and development of research and control of bovine tuberculosis is given on the occasion of Kurt Wagener's 100th birthday with special reference to his and his co-workers contributions to this subject. The topics as well concern the critical discussion of Ostertag's control measures and their replacement by Bang's methods as the importance of bovine tuberclebacilli as origin of human infections.

Tuberculosis (TB) began to decline in the Western world in the mid- to late 1800s. In the United States, the disease receded until the mid-1980s, when that trend was reversed. Although the TB epidemic in the United States subsided in response to public health interventions, it sparked a controversy regarding the relative value of targeted public health measures vs broad social reform. That controversy, which echoed earlier debates calling for structural reform over public health programs, was further strengthened by the historical and demographic studies of Thomas McKeown. His influential thesis maintains that clinical and primary prevention efforts had little effect on TB mortality. In this paper, the historical literature is used to examine whether public health had a significant impact on the decline of TB mortality rates in several countries. Specifically, the paper describes the arguments for and data affirming the efficacy of 2 major public health interventions over time: segregation of those infected with pulmonary TB and eradication of bovine TB. This review finds support for the hypothesis that public health measures, along with other factors, led to falling rates of TB mortality beginning in the late 19th century.

A decree of the Hannoverian sovereign GEORGE III passed in 1787 regarding the treatment of slaughtering cattle affected with tuberculous changes of the pleura is presented. Special emphasis is placed on the practice of food hygiene at that time and on the fact that the veterinarian was regarded an equal expert compared to the physician.

In the past zoonoses that caused serious human illness also caused serious loss of animal production, but there is growing awareness of the public health problems arising from infections that cause little or no such loss. Much can be learnt from the history of the control of bovine tuberculosis and brucellosis. In both cases there was reluctance to accept that animals were the principal cause of infection, and the earliest attempts at control failed because measures were taken only against clinical cases of the disease. The essential features in control of both infections were: official recognition of a problem, willingness of governments to allocate resources, and cooperation between the medical and veterinary professions. Salmonellosis is the most important zoonotic infection in Britain today, though several Orders have reduced the reservoir of infection in food animals. It is suggested that a national team of doctors should be set up to investigate and control zoonoses, that this team should be answerable to a central agency, and that it should build up close working relationships with the nominated officers of the veterinary profession.