How the Global Burden of Animal Diseases links to the Global Burden of Crop Loss: a food systems perspective.

Food systems comprise interconnected webs of processes that together transform inputs (land, labour, water, nutrients and genetics, to mention just a few) into outputs such as nutrition and revenue for human societies. Perfect systems do not exist; rather, global food systems operate in the presence of hazards, biotic and abiotic alike, and under the constraint of limited resources to mitigate these hazards. There are, therefore, inefficiencies in these systems, which lead to losses in terms of monetary, nutritional, health and environmental values and create additional negative externalities in the health, social and environmental spaces. Health hazards in the food system do not respect arbitrary distinctions between the crop and livestock sectors, which are highly interconnected. These linkages exist where one sector provides inputs to another or through substitution effects where supply in one sector influences demand in another. The One Health approach advocates investigating the intersectoral hazards in a highly interdisciplinary manner. This article provides a conceptual framework for integrating the methodologies developed by the Global Burden of Crop Loss and Global Burden of Animal Diseases initiatives to generate burden estimates for hazards in food systems that better account for interconnectivity and foster an improved understanding of food systems that is aligned with the interdisciplinary nature of the One Health approach. A case study related to maize and poultry sector linkages in the wider context of public and environmental health is presented.

Les systèmes alimentaires sont des réseaux de processus interconnectés qui concourent à transformer des intrants (terre, main-d'oeuvre, eau, nutriments et génétique, pour n'en mentionner que quelques-uns) en extrants tels que des aliments et des revenus pour les sociétés humaines. Il n'existe pas de système parfait ; les systèmes alimentaires mondiaux sont exposés en permanence à des dangers de nature tant biotique qu'abiotique et contraints par les ressources limitées consacrées à l'atténuation de ces dangers. Les problèmes d'efficacité sont donc inéluctables ; ils entraînent des pertes de valeur tant monétaire que nutritionnelle, sanitaire et environnementale, et génèrent de nouvelles externalités négatives dans le domaine de la santé ainsi que dans l'espace social et dans l'environnement. Les dangers sanitaires présents dans le système alimentaire ignorent les distinctions arbitraires entre les secteurs agricole et d'élevage, lesquels sont fortement interconnectés. Ces liens se manifestent lorsqu'un secteur fournit des intrants à l'autre et, par l'effet de substitutions, lorsque l'offre dans un secteur influence la demande dans l'autre. L'approche " Une seule santé " préconise d'adopter une méthode fondée sur l'interdisciplinarité pour enquêter sur les dangers intersectoriels. Les auteurs décrivent le cadre conceptuel de l'intégration des méthodes des initiatives " Fardeau mondial des pertes agricoles " et " Impact mondial des maladies animales " dans le but de produire des estimations de la charge induite par les dangers des systèmes alimentaires qui prennent davantage en compte leur inter-connectivité et donnent lieu à une meilleure compréhension des systèmes alimentaires, en cohérence avec le caractère interdisciplinaire de l'approche " Une seule santé ". Est également présentée une étude de cas portant sur les liens entre la culture du maïs et l'élevage de volailles dans le contexte plus large de la santé publique et environnementale.

Los sistemas alimentarios comprenden redes interconectadas de procesos que, conjuntamente, transforman insumos (tierra, mano de obra, agua, nutrientes y genética, por mencionar solo algunos) en productos como alimentos e ingresos para las sociedades humanas. No existen sistemas perfectos; más bien, los sistemas alimentarios mundiales funcionan en un entorno de peligros, tanto bióticos como abióticos, y con las restricciones impuestas por los limitados recursos disponibles para mitigarlos. En estos sistemas se observan, por tanto, ineficiencias, que provocan pérdidas en términos monetarios, nutricionales, sanitarios y ambientales y que crean externalidades negativas adicionales en los ámbitos sanitario, social y ambiental. Los peligros para la salud en los sistemas alimentarios no atienden a distinciones arbitrarias entre los sectores agrícola y ganadero, que están muy interconectados. Estos vínculos surgen cuando un sector proporciona insumos a otro o a través de efectos de sustitución en los que la oferta de un sector influye en la demanda de otro. El enfoque de "Una sola salud" aboga por investigar los peligros intersectoriales de manera eminentemente interdisciplinaria. En este artículo se ofrece un marco teórico para la integración de las metodologías desarrolladas por las iniciativas dedicadas al impacto global de las pérdidas de cosechas y al impacto global de las enfermedades animales a fin de obtener estimaciones de los peligros en los sistemas alimentarios que tengan más en cuenta la interconexión y fomenten una mejor comprensión de los sistemas alimentarios acorde con el carácter interdisciplinario del enfoque de "Una sola salud". En este sentido, se presenta un estudio de caso relacionado con los vínculos entre los sectores del maíz y las aves de corral en el contexto más amplio de la salud pública y ambiental.

Spatial Analysis of Temporal Changes in the Pandemic of Severe Cassava Mosaic Disease in Northwestern Tanzania.

To improve understanding of the dynamics of the cassava mosaic disease (CMD) pandemic front, geospatial approaches were applied to the analysis of 3 years' data obtained from a 2-by-2° (approximately 222-by-222 km) area of northwestern Tanzania. In total, 80 farmers' fields were assessed in each of 2009, 2010, and 2011, with 20 evenly distributed fields per 1-by-1° quadrant. CMD-associated variables (CMD incidence, CMD severity, vector-borne CMD infection, and vector abundance) increased in magnitude from 2009 to 2010 but showed little change from 2010 to 2011. Increases occurred primarily in the two westernmost quadrants of the study area. A pandemic "front" was defined by determining the values of CMD incidence and whitefly abundance where predicted disease gradients were greatest. The pandemic-associated virus (East African cassava mosaic virus-Uganda) and vector genotype (Bemisia tabaci sub-Saharan Africa 1-subgroup 1) were both present within the area bounded by the CMD incidence front but both also occurred ahead of the front. The average speed and direction of movement of the CMD incidence front (22.9 km/year; southeast) and whitefly abundance front (46.6 km/year; southeast) were calculated, and production losses due to CMD were estimated to range from US$4.3 million to 12.2 million.

Analysis of Seasonal Risk for Importation of the Mediterranean Fruit Fly, Ceratitis capitata (Diptera: Tephritidae), via Air Passenger Traffic Arriving in Florida and California.

The Mediterranean fruit fly, Ceratitis capitata (Wiedemann), is one of the most economically damaging pests in the world and has repeatedly invaded two major agricultural states in the United States, Florida and California, each time requiring costly eradication. The Mediterranean fruit fly gains entry primarily in infested fruit carried by airline passengers and, since Florida and California each receive about 13 million international passengers annually, the risk of Mediterranean fruit fly entering the United States is potentially very high. The risk of passengers bringing the pest into Florida or California from Mediterranean fruit fly-infested countries was determined with two novel models, one estimated seasonal variation in airline passenger number and the other defined the seasonal and spatial variability in Mediterranean fruit fly abundance. These models elucidated relationships among the risk factors for Mediterranean fruit fly introduction, such as amount of passenger traffic, routes traveled, season of travel, abundance of Mediterranean fruit fly in countries where flights departed, and risk of the pest arriving at destination airports. The risk of Mediterranean fruit fly being introduced into Florida was greatest from Colombia, Brazil, Panama, Venezuela, Argentina, and Ecuador during January-August, whereas primarily the risk to California was from Brazil, Panama, Colombia, and Italy in May-August. About three times more Mediterranean fruit flies were intercepted in passenger baggage at airports in Florida than California, although the data were compromised by a lack of systematic sampling and other limitations. Nevertheless, this study achieved the goal of analyzing available data on seasonal passenger flow and Mediterranean fruit fly population levels to determine when surveillance should be intensified at key airports in Florida and California.