Zoonoses

Animals are all around us. We overlap with them in environments across the globe, which leads to myriad interactions, including shared infectious and parasitic diseases. Such diseases, known as zoonoses, are the focus of this book. Within its pages, the authors describe the nature and transmission of zoonoses, discuss the diseases of greatest concern, detail different protective measures, and examine the factors responsible for zoonosis emergence and evolution. This work encourages readers to delve deeper into the world of animals and microbes that surrounds us. It presents knowledge we must possess to better protect ourselves and, more importantly, to adopt a more holistic approach to our relationships with animals and the living world

Reliability of molecular host-identification methods for ticks: an experimental in vitro study with Ixodes ricinus

Background: Reliable information on host use by arthropod vectors is required to study pathogen transmission ecology and to predict disease risk. Direct observation of host use is often difficult or impossible and indirect methods are therefore necessary. However, the reliability of currently available methods to identify the last host of blood-feeding arthropods has not been evaluated, and may be particularly problematic for ticks because host blood has been digested at capture. Biases in host detection may lead to erroneous conclusions on both vector ecology and pathogen circulation. Methods: Here, we experimentally tested for biases in host detection using the generalist three-host tick Ixodes ricinus as a model system. We fed ticks using an artificial feeding system and amplified blood meal traces post-moult (i.e., in the succeeding unfed life stage) via both a quantitative real-time polymerase chain reaction assay and a reverse line blotting method. We then experimentally tested for three types of biases in host detection: 1) time post-moult, 2) tick life stage and 3) host type (non-nucleated mammal blood versus nucleated avian blood), and compared these biases between the two molecular methods. Results: Our results show that all three factors can influence host detection in ticks but not necessarily in the expected way. Although host detection rates decreased with time post-moult, mammal blood tended to be more readily detected than bird blood. Tick life stage was also an important factor; detection was higher in nymphs than in adults and, in some cases, remnants from both larval and nymphal blood meals could be detected in the adult stage. These biases were similar for the two detection techniques. Conclusions: We show that different factors associated with questing ticks may influence our ability to correctly infer previous host use and that these factors may bias inferences from field-based studies. As these biases may be common to other vector-borne disease systems, their implications for our understanding of vector ecology and disease transmission require more explicit consideration

Tiques, bactéries, réservoirs et maladies

International audienc

Les maladies émergentes : un défi pour le développement durable des productions animales

National audienceThis paper first displays the global framework for the study of emerging diseases aimed at disease control, sanitary crises avoidance and promotion of sustainable agriculture. Then, the research programmes, stages, methods and tools that are needed for emerging disease study and control are presented. These are either already available, under development or awaiting for research studies. They mainly concern information systems, biomathematics, epidemiological methods and molecular biology markers. Finally, some of the main organisational principles (synergies between health protagonists: veterinarians, herdsmen, researchers, health managers, local authorities) are introduced. These principles have to be satisfied if we want to reach an efficient vigilance towards potentially emerging diseases and to take up the challenge that is facing animal populations and human societies en route for globalisation.L’article présente d’abord le cadre global de l’étude des maladies émergentes à des fins de contrôle, d’évitement des crises sanitaires et de promotion d’une agriculture durable. Sont ensuite passées en revue les réalisations actuelles et les différentes étapes, méthodes et outils existants, en cours de mise au point ou qui nécessitent un travail de recherche (en matière de systèmes d’information, de méthodes biomathématiques, de stratégies épidémiologiques et de marqueurs de biologie moléculaire) afin d’être adaptés à l’étude des émergences. Au bout du compte, sont posés quelques principes d’organisation (synergies entre les acteurs du sanitaire : vétérinaires, éleveurs, chercheurs, gestionnaires de la santé, collectivités locales) à concrétiser pour aboutir à une vigilance efficace vis-à-vis des maladies potentiellement émergentes et pouvoir relever au mieux le défi qu’elles posent aux sociétés animales et humaines en voie de globalisation

Annexe 5

Identifier l’hôte du repas sanguin d’un arthropode vecteur est essentiel pour étudier l’évolution et le comportement des arthropodes hématophages, ainsi que pour comprendre l’épidémiologie et l’émergence d’une maladie vectorisée dans un écosystème donné. Du début du XXe siècle à aujourd’hui, l’identification de l’hôte du repas sanguin a été réalisée par des techniques sérologiques telles que le test aux précipitines (dos Santos Silva et al., 2012) ou la méthode ELISA (Marassa et al., 2008). À..

Stratégies et synergies autour de l'étude épidémiologique des maladies animales émergentes. Un programme transversal / Un outil générique Oracle-Internet-Java

International audienc

Stratégies et synergies autour de l'étude épidémiologique des maladies animales émergentes. Un programme transversal / Un outil générique Oracle-Internet-Java

International audienc