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

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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..

Inclusion of citizens in the design of livestock farming. Case of mid-moutain dairy system.

International audienc

Including citizens through co-design in a participatory research project to explore innovative agro-food systems :: the case of future dairy livestock systems

International audienceIntroduction Livestock farming and its negative impacts are increasingly criticized by society; its evolution toward more sustainable systems is therefore a key aspect of the transition of agro-food systems. It is necessary to rethink livestock systems' research and innovation processes and develop innovative solutions. Including citizens, non-professionals of the sector, who are less influenced by the current organization of the agricultural sector could be an opportunity to generate innovative solutions, but they have been kept away from research and innovation processes so far. Methods In this context, we implemented a co-design process involving researchers, livestock professionals, and citizens in a participatory research project aiming at producing knowledge and developing innovative solutions for the future mountain dairy systems. For this, we have adapted the KCP design method known to promote the exploration of innovative solutions, support the agro-ecological transition, and build a common horizon. Results The analysis of this collective dynamic and its outputs allowed us to highlight the positive contribution of citizens during the design process, even if they are not livestock experts. The citizens participated in the formulation of new knowledge by questioning the researchers and livestock professionals and were less influenced by the current system. This contributed to the exploration of original and varied solutions for livestock farming systems. Discussion This experimentation offers perspectives for including citizens in agro-food systems research and innovation process. It also opens up interesting perspectives for the fields of citizen science and co-design research

Reproducibility of local environmental factors for the abundance of questing Ixodes ricinus nymphs on pastures.

International audienceIn ecology and epidemiology, exploratory field studies based on multivariate statistical models commonly are used to identify factors that are associated with a phenomenon. The challenge is to evaluate whether these factors are indeed correlated to the phenomenon or if the statistical significance results from fortuitous association or type 1 statistical error (probability of rejecting a null hypothesis when it is true). This is particularly the case when the phenomenon is linked to environmental factors that usually are more or less correlated to each other and when the phenomenon is itself highly variable. The abundance of Ixodes ricinus ticks, a major disease vector in Europe, is highly variable and depends on environmental conditions that define suitable habitat and host presence. Our objective was to identify reproducible factors in space and time that influenced the abundance of questing I. ricinus nymphs. We sampled questing nymphs in pastures in 4 settings, i.e. during 3 periods (2003, 2004, and 2006) in one region, and during one period (2006) in another region, both regions located in Central France. The same data collection, data selection, and model analysis using negative binomial distribution were applied independently in the 4 data sets to identify [`]reproducible' factors, i.e. explanatory factors that were significant in different time periods and spaces. The 3 most reproducible factors suggested that woodland type vegetation and woodland vicinity constantly favoured nymph abundance on pastures. In addition, the presence of fruit trees was significantly associated with nymph abundance in one region. The other factors were not reproducible. The study confirmed the status of key factors for nymph abundance while avoiding having to redefine the statistical model to model the different sampling conditions. It also shows the difficulty to identify factors with general significance acting on a very variable phenomenon, based on a study made one year in one region. Relevant study design should consider appropriate repetitions based on the range of values of the studied factors. Furthermore, discussion of the results is essential to identify factors that have a general significance