Decisions to manage endemic ectoparasites: the case of ticks and tick-borne diseases in northern Australia.

Control of ticks and tick-borne diseases in northern Australia is considered economically important, but is complicated due to the physical and production environment. Various approaches to analysis have been applied to evaluate decisions to control tick-borne diseases but have been used in research rather than as direct support for producer decisions. To be effective, the results from economic analysis need to be applied by decision-makers. The application of the results from economic analysis requires decision-makers and analysts to incorporate effective communication within their relationship. Taking a learning approach to enhance communication in economic advisory services has potential to overcome misalignment between the advice provided and producers' approaches to decision-making. In this approach, we need to understand the processes a livestock producer would use to evaluate their experiences and develop new understanding and knowledge over time as a result of these experiences. This paper explores the nature of private decisions in relation to tick-borne disease control then considers the use of a learning approach to enable effective learning to take place between producers and their advisors.

Le contrôle des tiques et des maladies transmises par les tiques dans le nord de l'Australie est considéré comme une priorité économique, mais sa réussite est rendue difficile par les contraintes physiques et de production. Les décisions en matière de lutte contre les maladies transmises par les tiques ont été évaluées en recourant à diverses méthodes d'analyse, mais davantage dans le cadre de la recherche que pour soutenir directement les décisions des producteurs. Or, pour être efficaces, les conclusions d'une analyse économique doivent être appliquées par les décideurs. Pour ce faire, il faut que les décideurs et les analystes intègrent les principes d'une communication efficace dans leurs relations de travail. La mise en oeuvre d'une démarche apprenante pour améliorer la communication dans le cadre des prestations de conseils économiques permet de résoudre les problèmes d'inadéquation entre le conseil fourni et les méthodes de prise de décision suivies par les éleveurs. Dans cette démarche, il s'agit de comprendre les processus suivis par un éleveur pour évaluer son expérience et pour élaborer une nouvelle vision et acquérir de nouvelles connaissances à la faveur de cette expérience. L'auteur examine la nature des décisions privées concernant la lutte contre les maladies transmises par les tiques ainsi que l'importance d'une approche apprenante pour qu'un véritable apprentissage ait lieu entre les éleveurs et leurs conseillers.

Aunque se considera económicamente importante, la lucha contra las garrapatas y las enfermedades transmitidas por ellas en el septentrión australiano se ve complicada por las condiciones de producción y el entorno físico. Para evaluar las decisiones encaminadas a combatir esas enfermedades se han utilizado distintos métodos de análisis, pero más bien con fines de investigación que como elemento de apoyo directo a la adopción de decisiones sobre producción. Para que los resultados del análisis económico sean eficaces, es preciso que quienes toman decisiones los apliquen, lo que a su vez exige que tanto quienes deciden como los analistas integren una comunicación eficaz como parte de su relación. El hecho de abordar la cuestión pensando en aprender cómo mejorar la comunicación que se establece en los servicios de asesoramiento económico abre la posibilidad de superar el desfase entre el asesoramiento ofrecido y la forma en que los productores adoptan decisiones. Para ello es menester los procesos que seguirá un productor ganadero para evaluar su experiencia y a partir de ahí, con el tiempo, ir ganando en comprensión y conocimiento. Tras estudiar la naturaleza de las decisiones privadas en todo lo tocante a la lucha contra las enfermedades transmitidas por garrapatas, el autor examina el uso de métodos de aprendizaje para lograr que entre los productores y sus asesores se genere una dinámica eficaz de aprendizaje.

The economic implications of animal diseases and disease control at the national level.

The authors examine the economic implications of animal diseases and control programmes at the national level, including the role of government in animal health, the effect of regulations and the use of cost-benefit analysis. Special attention is paid to the role of economic analysis in government decision-making processes. Economics provides a framework for gathering information and for the presentation of that information in a methodical manner, thereby providing a method for the decision maker to examine policy alternatives. In addition, assumptions underlying the analysis must be clearly laid out and explained by the person undertaking the analysis. Economic reasons for government intervention in animal health programmes include externalities, natural monopolies, public goods, coordination failure, information failure and distribution issues. An integrated holistic approach that includes national and international policy objectives is outlined in the paper. In the approach outlined, government coordinates the activities of stakeholders in animal health, including producers, consumers and researchers.

The economic impacts of endemic diseases and disease control programmes.

The authors discuss the evaluation of the economic impacts of endemic livestock diseases, and economic issues in control of these diseases. Particular attention is focused on helminths and on endemic vector-transmitted infections (particularly ticks and tick-borne diseases). Decisions relating to disease control have to be made by government and by the producer. Government requires information on the level of control to adopt, the extent of involvement needed, and how to fund animal health programmes (particularly how to share costs between taxpayers and livestock producers). Individual producers require information as to how much effort to invest in disease control, including information collection effort, and how to design control strategies. Economics can shed light on these issues. However, experience suggests that animal health policies are particularly difficult to evaluate from an economic viewpoint, with complex relationships between animal health, production impacts, market access, and non-production benefits of livestock. While little information is available concerning the cost of helminth diseases, many estimates have been made of the costs of ticks and tick-borne diseases at a regional and national level, sometimes demonstrating that eradication is warranted.

Protracted yet variable major pulmonary artery compression in sarcoidosis.

A case of thoracic sarcoidosis showing diffuse mediastinal lymphadenopathy was followed for a 6-month period with serial chest radiographs, perfusion lung scans, and pulmonary angiograms. Significant extrinsic pressure upon major pulmonary arteries from large lymph nodes of sarcoidosis was seen to cause marked restriction in pulmonary parenchymal perfusion on both scanning and angiography.