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International audience; In wildlife ecotoxicology, the rationale for using blood rather than other body fluids or tissues is that sampling blood is a minimally invasive technique without animal mortality, providing both ethical and scientific benefits. To date, few studies are available on the relationships between blood and organ metal concentrations of small mammals living in contaminated sites. The present work aimed to study the relationships between the concentrations of 18 essential and nonessential metals in blood and their concentrations in the liver and kidneys, two accumulation and target organs, in wood mice from a former lead and zinc smelter, Metaleurop Nord, in northern France. The results from Se, Pb and Tl indicate that blood levels may be used to predict concentrations in organs of small mammals. Conversely, for Cd, Cu, Fe, Mo, Ti and Zn, blood concentrations were poorly or not related to liver and kidney concentrations. In addition to accurately predicting the concentrations of some metals in target organs, blood can provide important information about the physiological and biochemical status of organisms, but further toxicokinetic research is required to develop the use of blood sampling as a minimally invasive biomonitoring and ecotoxicological method in wildlife.

Pollution with trace metals (TM) has been shown to affect diversity and/or composition of plant and animal communities. While ecotoxicological studies have estimated the impact of TM contamination on plant and animal communities separately, ecological studies have widely demonstrated that vegetation is an important factor shaping invertebrate communities. It is supposed that changes in invertebrate communities under TM contamination would be explained by both direct impact of TM on invertebrate organisms and indirect effects due to changes in plant communities. However, no study has clearly investigated which would more importantly shape invertebrate communities under TM contamination. Here, we hypothesized that invertebrate communities under TM contamination would be affected more importantly by plant communities which constitute their habitat and/or food than by direct impact of TM. Our analysis showed that diversity and community identity of flying invertebrates were explained only by plant diversity which was not affected by TM contamination. Diversity of ground-dwelling (GD) invertebrates in spring was explained more importantly by plant diversity (27% of variation) than by soil characteristics including TM concentrations (8%), whereas their community identity was evenly explained by plant diversity and soil characteristics (2-7%). In autumn, diversity of GD invertebrates was only explained by plant diversity (12%), and their identity was only explained by soil characteristics (8%). We conclude that vegetation shapes invertebrate communities more importantly than direct effects of TM on invertebrates. Vegetation should be taken into account when addressing the impacts of environmental contamination on animal communities.

International audience; Pollution with trace metals (TM) has been shown to affect diversity and/or composition of plant and animal communities. While ecotoxicological studies have estimated the impact of TM contamination on plant and animal communities separately, ecological studies have widely demonstrated that vegetation is an important factor shaping invertebrate communities. It is supposed that changes in invertebrate communities under TM contamination would be explained by both direct impact of TM on invertebrate organisms and indirect effects due to changes in plant communities. However, no study has clearly investigated which would more importantly shape invertebrate communities under TM contamination. Here, we hypothesized that invertebrate communities under TM contamination would be affected more importantly by plant communities which constitute their habitat and/or food than by direct impact of TM. Our analysis showed that diversity and community identity of flying invertebrates were explained only by plant diversity which was not affected by TM contamination. Diversity of ground-dwelling (GD) invertebrates in spring was explained more importantly by plant diversity (27% of variation) than by soil characteristics including TM concentrations (8%), whereas their community identity was evenly explained by plant diversity and soil characteristics (2–7%). In autumn, diversity of GD invertebrates was only explained by plant diversity (12%), and their identity was only explained by soil characteristics (8%). We conclude that vegetation shapes invertebrate communities more importantly than direct effects of TM on invertebrates. Vegetation should be taken into account when addressing the impacts of environmental contamination on animal communities.

International audience; The eggs of Echinococcus multilocularis, the infectious stage, are spread into the environment through wild and domestic carnivore faeces. The spatial location of the faeces containing infective E. multilocularis eggs is a key parameter for studying areas of exposure and understanding the transmission processes to the intermediate hosts and humans. Echinococcus multilocularis faecal prevalence is often assessed by detecting E. multilocularis DNA, not necessarily eggs. This work aimed to determine the percentage of faeces containing E. multilocularis eggs in a rural town and its surroundings and whether this level of precision is relevant in assessing exposure to E. multilocularis. For this purpose, we developed a combined molecular and microscopic approach to investigate the E. multilocularis exposure of potential hosts in the environment from field-collected carnivore faeces. Carnivore defecation patterns were then spatialized to study the spatial distribution of E. multilocularis. Faeces were screened for E. multilocularis DNA using a specific real-time quantitative PCR (qPCR). Echinococcus multilocularis eggs were morphologically identified from E. multilocularis-specific qPCR-positive faeces after sucrose flotation and individually confirmed through specific PCR and sequencing. The spatial distribution of E. multilocularis was studied using Kulldorff statistics. Echinococcus multilocularis eggs were identified mostly in fox faeces positive for E. multilocularis DNA by qPCR (n = 27/70) and only from 1 of 15 copro-samples from dogs and 1 of 5 from cats. The faecal prevalence of E. multilocularis DNA and eggs was overdispersed, with the same geographical patterns. These data suggest that E. multilocularis DNA and/or egg detection in carnivore faeces, mainly that of foxes, is appropriate in ecological studies of E. multilocularis transmission.

Background Bacterial meningitis remains a major threat for the population of the meningitis belt. Between 2004 and 2009, in the countries of this belt, more than 200,000 people were infected with a 10% mortality rate. However, for almost 20 years, important meningitis epidemics are also reported outside this belt. Research is still very poorly developed in this part of the word like in the Democratic Republic of Congo (DRC), which experiences recurrent epidemics. This article describes for the first time the spatio-temporal patterns of meningitis cases and epidemics in DRC, in order to provide new insights for surveillance and control measures. Methods Based on weekly suspected cases of meningitis (2000–2012), we used time-series analyses to explore the spatio-temporal dynamics of the disease. We also used both geographic information systems and geostatistics to identify spatial clusters of cases. Both using conventional statistics and the Cleveland’s algorithm for decomposition into general trend, seasonal and residuals, we searched for the existence of seasonality. Results We observed a low rate of biological confirmation of cases (11%) using soluble antigens search, culture and PCR. The main strains found are Streptococcus pneumoniae, Haemophilus influenzae and Neisseria meningitidis (A and C) serogroups. We identified 8 distinct spatial clusters, located in the northeastern and southeastern part of DRC, and in the capital city province, Kinshasa. A low seasonal trend was observed with higher incidence and attack rate of meningitis during the dry season, with a high heterogeneity in seasonal patterns occurring across the different districts and regions of DRC. Conclusion Despite challenges related to completeness of data reporting, meningitis dynamics shows weak seasonality in DRC. This tends to suggest that climatic, environmental factors might be less preponderant in shaping seasonal patterns in central Africa. The characterization of 8 distinct clusters of meningitis could be used for a better sentinel meningitis surveillance and optimization of vaccine strategy in DRC. Improving biological monitoring of suspected cases should be a priority for future eco-epidemiological studies to better understand the emergence and spread of meningitis pathogens, and the potential ecological, environmental drivers of this disease.

International audience; Exposure of terrestrial mammals to chemical contaminants like trace metals (TMs) is considered to be mainly based on trophic transfer. Although relationships between TM transfer to animals and identity of contaminated food have been studied, the variation of the TM transfer with respect to diet diversity has been poorly documented. In this study, the oral exposure to TMs of wood mice Apodemus sylvaticus was investigated with respect to both the number of different items, i.e., diet richness, and the identity of items determined by metabarcoding from their stomach content, i.e., diet composition. The results showed that consuming Salicaceae, a known cadmium accumulator plant family, significantly increased exposure to cadmium and zinc. However, an increase in diet richness minimized exposure to cadmium when mice consumed Salicaceae items. This strongly suggests that TM accumulator items can lead to a high oral exposure to TMs but that such high exposure due to TM accumulator items can be "diluted" by diet richness due to other low accumulator items. Our results clearly indicate that both the presence of certain items in the diet and diet richness are important determinants of exposure to TMs in generalist animals, which matches the predictions of the "diet dilution hypothesis".

International audience; Mammals are mainly exposed to trace metals (TMs) via consuming contaminated food. Several studies have demonstrated relationships between metal concentrations in food and in animal tissues. However, potential effects of TMs on feeding behaviour of wildlife have been poorly documented under field conditions, despite experimental evidence showing that food selection is impacted by resource contamination. Here, we test the hypothesis that the diet of a generalist rodent, the wood mouse (Apodemus sylvaticus), is altered by soil TM contamination in the field. Wood mice were sampled in spring and in autumn along a gradient of soil contamination in the surroundings of a former smelter located in northern France. Available resources in the field were inventoried, and the diet of the animals was analysed using DNA metabarcoding. We demonstrated that (a) relationship between the resource richness in the diet and their richness in the field was altered by soil metal contamination. Wood mice specialized their dietalong the gradient of soil metal contamination for both plant and invertebrate resources in spring. We also showed that (b) preference for Salicaceae, a plant family accumulating metals, decreased when soil contamination increased. These results suggest that environmental TM pollution could act as a force modulating trophic interactions in terrestrial food webs, thereby affecting wildlife exposure to contaminants by trophic route.

Within the current context of global change, ecosystems face simultaneously multiple stressors such as environmental pollution, excessive enrichment, and additional disturbances affecting population dynamics. Numerous theoretical and empirical studies explored the transfer of contaminants by food ingestion between trophic levels, and how contaminant effects on survival and fecundity may change regime shifts of classical predator–prey dynamics. However, the extent to which those contaminants may influence the cascade effect of external stressors, as a change in resources (bottom-up cascade) or a variation in predator abundance (top-down cascade) is still poorly understood. We develop a data-driven model to explore how soil contamination modulates the food chain stability and resilience to changes in prey nutrient and in the apex predator mortality rate. We particularly focus on the ecotoxicological impact of the trace metal, cadmium, on a widespread raptor, the barn owl (Tyto alba), feeding on several prey distinct by their trophic positions: herbivores (Microtus spp.), omnivores (wood mouse Apodemus sylvaticus and bank vole Myodes glareolus) and insectivores (shrews: Crocidura spp. and Sorex spp.). Our model reveals the alternative steady states in population dynamics and the occurrence and position of regime shifts where a subtle change in conditions causes a sudden shift in the ecological system. Based on mathematical modelling and bifurcation analysis, the results show for instance that under toxicity threshold, where no population decline is observed, the contaminant weakens food-chain resilience. Then at higher contamination, the toxic effects on predator releases the top-down control over prey that may increase. This range of chemical stress overturns the paradox of enrichment, a central concept in trophic cascade theory. The transition phase at the highest contamination, where the whole community collapse, exhibits multiple patterns, from smooth to abrupt, depending on external stressors and the prey population. Thus, this work provides a methodology to identify ecological traits of preys that are critical for transferring adverse effects of contaminants across the whole community.

Background\ud The eastern part of the Tibetan Plateau is now recognized as an endemic region with the highest reported human infection rates in the world of human alveolar echinococcosis (AE) caused by Echinococcus multilocularis. Existing epidemiological studies on AE have mainly focused on the synanthropic environment, while basic parasitological and ecological aspects in wildlife host species remain largely unknown, especially for small mammal hosts. Therefore, we examined small mammal host species composition, occurrence, and the prevalence of both E. multilocularis and E. shiquicus in Shiqu County (Sichuan Province, China), eastern Tibetan Plateau.\ud \ud Results\ud In total, 346 small mammals from five rodent and one pika species were trapped from four randomly set 0.25 ha square plots. Two vole species, Lasiopodomys fuscus (n = 144) and Microtus limnophilus (n = 44), and the plateau pika (Ochotona curzoniae) (n = 135), were the three most-dominant species trapped. Although protoscoleces of E. multilocularis and E. shiquicus were only observed in L. fuscus and O. curzoniae, respectively, cox1 and nad1 gene DNA of E. shiquicus was detected in all the small mammal species except for Neodon irene, whereas E. multilocularis was detected in the three most-dominant species. The overall molecular prevalence of Echinococcus species was 5.8 (95% CI: 3.3–8.2%) ~ 10.7% (95% CI: 7.4–14.0%) (the conservative prevalence to the maximum prevalence with 95% CI in parentheses), whereas for E. multilocularis it was 4.3 (95% CI: 2.2–6.5%) ~ 6.7% (95% CI: 4.0–9.3%), and 1.5 (95% CI: 0.2–2.7%) ~ 4.1% (95% CI: 2.0–6.1%) for E. shiquicus. The prevalence of both E. multilocularis and E. shiquicus, was significantly higher in rodents (mainly voles) than in pikas. Phylogenetic analyses revealed that Echinococcus haplotypes of cox1 from small mammal hosts were actively involved in the sylvatic and anthropogenic transmission cycles of E. multilocularis in the eastern Tibetan Plateau.\ud \ud Conclusions\ud In contrast to previous studies, the current results indicated that rodent species, rather than pikas, are probably more important natural intermediate hosts of E. multilocularis and E. shiquicus in the eastern Tibetan Plateau. Thus, understanding interspecific dynamics between rodents and pikas is essential to studies of the echinococcosis transmission mechanism and human echinococcosis prevention in local communities.\ud \ud Keywords:\ud Echinococcus multilocularis, E. shiquicus, Small mammal Prevalence, Tibetan Plateau

The life cycle of the cestode Echinococcus multilocularis primarily involves canids and small mammals (rodents, lagomorphs) as definitive and intermediate hosts, respectively. Several surveys have identified marked temporal and geographical variations at different scales in the parasite’s prevalence in both types of hosts, suggesting variations in the biological and ecological factors that control transmission processes. The parasite transmission from intermediate to definitive hosts is determined by the predator–prey relationship, which theoretically depends on prey population dynamics and the complex dietary response of predators to varying densities of prey species and other food items. Parasite eggs are transmitted to intermediate hosts via carnivore faeces, whose distribution in the environment is driven by the defecating behaviour of final hosts. We reviewed field-based studies that address issues related to the trophic ecology and behaviour of definitive hosts, interactions between definitive and intermediate hosts, and E. multilocularis transmission both in wild and domestic animals in rural and urban environments. Two density-dependent mechanisms control the transmission dynamics in definitive hosts: one is based on the variations in the availability of intermediate hosts, and the other is based on the variations in the density of the definitive host and its faeces. Non-linearity and the direct and delayed responses of definitive host contamination in relation to intermediate host population variations were recorded. The dietary response of the red fox was shown to be complex when abundant alternative resources were available (anthropogenic food, multiple intermediate host prey species). Micro-local hotspots of parasite transmission to intermediate hosts in a landscape, as well as areas of higher risk for human contamination in village and urban settings, may be explained by the definitive hosts’ activity patterns and defecation behaviour.

International audience; Palm oil is nowadays the first vegetable oil consumed worldwide. Given the world population growth and the increasing demand in fat for food and fuel, the increase in oil palm production is expected to continue. It is thus important to find ways of reducing the ecological impact of oil palm plantations at both the agroecosystem and the mill supply area levels, by improving agricultural practices and land uses. This is where agroecology can play a very critical role. The present article gathers short stories on agroecological practices currently taking place in oil palm plantations in South-East Asia. Such stories notably highlight the importance of the various palm co-products and how appropriate recycling strategies can allow for reducing external inputs to both the field and the mill. Besides limiting environmental impacts thanks to such savings, several co-products used as organic amendments can even help to maintain or enhance soil quality. Other stories explored agroecological practices developed for biological controls. Although integrated pest management has been applied in palm plantations for a long time, the underlying mechanisms are still not fully deciphered and practices still need to be improved. More knowledge is needed in order to better account for the holistic role of biodiversity and arbitrate trade-offs between practices and ecosystem services, at both plantation and landscape levels.; L'huile de palme est aujourd'hui la première huile végétale consommée au monde. Étant donné la croissance démographique mondiale et la demande accrue en corps gras pour l'alimentation et les biocarburants, l'augmentation de la production d'huile de palme devrait perdurer. Il est ainsi primordial de trouver des moyens de production permettant de réduire l'impact écologique des plantations de palmier à huile, à la fois à l'échelle de l'agroécosystème et celle du bassin d'approvisionnement de l'huilerie, en améliorant les pratiques et la gestion des usages des sols. Les principes de l'agroécologie peuvent aider à développer des solutions à ces diverses échelles. Cet article rassemble diverses histoires courtes illustrant des pratiques agroécologiques mises en place dans des plantations de palmier à huile en Asie du Sud-Est. Ces illustrations mettent en évidence l'importance des nombreux co-produits issus du palmier et leur rôle clé dans les stratégies de recyclage pour réduire le recours aux intrants externes pour la plantation comme pour l'huilerie. Au-delà de la réduction des impacts environnementaux du fait de ces économies d'intrants, certains co-produits restitués en plantation peuvent également permettre de maintenir, voire d'améliorer, la qualité des sols. D'autres histoires courtes parcourent quelques autres pratiques agroécologiques dans le domaine de la lutte intégrée. Bien que de nombreuses pratiques de contrôle biologique soient mises en œuvre dans des plantations de palmier à huile depuis de nombreuses années, les mécanismes sous-jacents ont été encore peu explorés et les pratiques peuvent être améliorées. De nouvelles connaissances sont nécessaires pour mieux caractériser et prendre en compte de manière holistique les enjeux et le rôle de la biodiversité et pouvoir arbitrer les compromis entre pratiques et services écosystémiques, aux échelles de la plantation et du paysage.

International audience; Evolution and dispersion history on Earth of organisms can best be studied through biological markers in molecular epidemiological studies. The biological diversity of the cestode Echinococcus multilocularis was investigated in different cladistic approaches. First the morphological aspects were explored in connection with its ecology. More recently, molecular aspects were investigated to better understand the nature of the variations observed among isolates. The study of the tandemly repeated multilocus microsatellite EmsB allowed us to attain a high genetic diversity level where other classic markers have failed. Since 2006, EmsB data have been collected on specimens from various endemic foci of the parasite in Europe (in historic and newly endemic areas), Asia (China, Japan and Kyrgyzstan), and North America (Canada and Alaska). Biological data on the isolates and metadata were also recorded (e.g. host, geographical location, EmsB analysis, citation in the literature). In order to make available the data set of 1,166 isolates from classic and aberrant domestic and wild animal hosts (larval lesions and adult worms) and from human origin, an open web access interface, developed in PHP, and connected to a PostgreSQL database, was developed in the EmsB Website for the Echinococcus Typing (EWET) project. It allows researchers to access data collection, perform genetic analyses online (e.g. defining the genetic distance between their own samples and the samples in the database), consult distribution maps of EmsB profiles, and record and share their new EmsB genotyping data. In order to standardize the EmsB analyses performed in the different laboratories throughout the world, a calibrator was developed. The final aim of this project was to gather and arrange available data to permit to better understand the dispersion and transmission patterns of the parasite among definitive and intermediate hosts, in order to organize control strategies on the ground.

Aim The Llanos de Ojuelos in Mexico's Central High Plateau supports unique Opuntia scrublands and the southernmost Chihuahuan grasslands. Although human activities have modified strongly its landscape and impacted its biodiversity at an unknown scale, such impacts are poorly known. We aimed at understanding how nocturnal rodent species distributed across the landscape and formed assemblages and on the role and integration of the different habitats at the landscape level. Location The study was carried out at 43 sites in a study area of approximately 3350 km2 in the Llanos de Ojuelos Methods During the Spring of 2008, we surveyed nocturnal rodents, through live-trapping. We redefined habitat classes based on log-linear multinomial regressions of rodent captures. Species rarefaction curves and true alpha, beta and gamma diversities were calculated for the different habitat classes. A map of the different habitats was constructed based on Landsat imagery. Results We captured 458 individuals of 20 rodent species. Multinomial regressions caused the merger of 11 a priori defined habitat classes into 7. Leguminous scrub and mixed nopaleras, both secondary habitats, had the highest alpha and gamma diversity values. Closed arboreal nopaleras and grasslands had the highest within-habitat variability (1Db) and the lowest area coverage. Within habitat 1Db was larger than landscape 1Db, because of the great overlap in rodent assemblage composition between the habitats. Main conclusions There are no 'typical' rodent assemblages per habitat class, but they are organized loosely and have fuzzy borders. Rodent community organization was highly species-centred. At the landscape level, secondary habitats have a profound effect on rodent diversity and should be included in management schemes for biological conservation. The most endangered habitats seem to be the closed arboreal nopaleras and grasslands. Any conservation efforts must consider their conservation and an increase in the size of remaining patches.

Alveolar echinococcosis is restricted geographically to the colder areas of the northern hemisphere. In France, the highest prevalence is observed in Franche-Comtd. The yearly incidence of AE in endemic areas is generally low (0.02-0.18 per 100,000 inhabitants) but it can exceed 1 per 100,000 locally. E. multilocularis transmission has intensified in traditionally in foxes endemic areas during the last twenty years, and the parasite has extended its range to new areas and countries of Europe. The increasing proximity of fox populations to urban areas may lead to a new epidemiological pattern. Control measures are only applicable at the local scale, and are essentially based on for deworming.

International audience; Echinococcus multilocularis is the causative agent of human Alveolar Echinococcosis (AE), and it is one of the most lethal zoonotic infections in the Northern Hemisphere. In France, the eastern and central regions are endemic areas; Franche-Comt?Lorraine and Auvergne are particularly contaminated. Recently, several human cases were recorded in the French Ardennes area, a region adjacent to the western border of the E. multilocularis range in France. A previous study in this focus described a prevalence of over 50% of the parasite in red foxes. The present study investigated the genetic diversity of adult worms collected from foxes in a 900km(2) area in the Ardennes. Instead of a conventional mitochondrial target (ATP6), two microsatellite targets (EmsB and NAK1) were used. A total of 140 adult worms isolated from 25 red foxes were genotyped. After hierarchical clustering analyses, the EmsB target enabled us to distinguish two main assemblages, each divided into sub-groups, yielding the differentiation of six clusters or assemblage profiles. Thirteen foxes (52% of the foxes) each harbored worms from at least two different assemblage profiles, suggesting they had become infected by several sources. Using the NAK1 target, we identified 3 alleles, two found in association with the two EmsB assemblages. With the NAK1 target, we investigated the parasite breeding system and the possible causes of genetic diversification. Only one fox harbored hybrid worms, indicative of a possible (and rare) occurrence of recombination, although multiple infections have been observed in foxes. These results confirm the usefulness of microsatellite targets for assessing genetic polymorphism in a geographically restricted local range.

International audience; The completion of the life cycle of Echinococcus multilocularis needs a spatial overlap between intermediate host species (voles) and definitive host (fox) faeces. Factors influencing the importance of this overlap were investigated in north eastern France. Kilometric transects were walked to collect fox faeces and to estimate vole relative densities through surface indices. Habitat and climatic conditions were the strongest predictors of the number of faeces collected, while vole densities had no predictive power. Densities of both Microtus sp. and fox faeces were higher in medium-height vegetation edge. The consequences of such results to understand local transmission processes and human exposure are discussed.

Understanding the transmission ecology of parasites involves the challenge of studying the complexity of life-cycles at multiple levels of biological organisation and at various space-time scales. We think that a single field of science alone cannot fully address this issue and that a way to understand such complexity is to connect various fields of science, to consider the whole transmission system, and to identify which are the variables reasonably accessible to measurement and the relevant scales at which they may provide information about transmission processes and indicate a higher risk of transmission⁄emergence. Based on ongoing studies carried out in Europe and in China, the aim of the present paper is to discuss this approach and to show how results obtained from mass-screening of human populations may be combined to those obtained from small mammal and landscape ecology studies and modelling to promote an understanding of Echinococcus multilocularis transmission and to determine how differences in the time-space scales at which human infection and small mammal population dynamic processes occur may complicate the analysis.

International audience; The ability for a generalist consumer to adapt its foraging strategy (the multi-species functional response, MSFR) is a milestone in ecology as it contributes to the structure of food webs. The trophic interaction between a generalist predator, as the red fox or the barn owl, and its prey community, mainly composed of small mammals, has been empirically and theoretically widely studied. However, the extent to which these predators adapt their diet according to both multi-annual changes in multiple prey species availability (frequency dependence) and the variation of the total prey density (density dependence) is unexplored.We provide a new general model of MSFR disentangling changes in prey preference according to variation of prey frequency (switching) and of total prey density (we propose the new concept of “rank switching”). We apply these models to two large data sets of red fox and barn owl foraging. We show that both frequency-dependent and density-dependent switching are critical properties of these two systems, suggesting that barn owl and red fox have an accurate image of the prey community in terms of frequency and absolute density. Moreover, we show that negative switching, which can lead to prey instability, is a strong property of the two systems.

International audience; For sustainable oil palm production, barn owl (Tyto alba) predation should be enhanced and monitored to better understand its impact on rodent population dynamics, notably for selective predation based on age or size. Our aim was to assess the best combination of osteometric variables that predict eye lens weight and thus the relative age of an individual Rattus tiomanicus based on pellet remains. We captured 161 individuals in an oil palm plantation in Indonesia and measured 15 osteometric variables for the jaw, skull, and femur. We investigated the variables’ correlations with eye lens weight and estimated the measurement errors. In addition, 120 pellets were collected to assess the frequency of different types of bones. Predictive modelling was then used. We suggest that the model using the femur length would be more appropriate, even if it is slightly less precise than the models that consider the skull and jaw variables. The femur was well represented in the pellet sample, its length highly correlated with the eye lens weight, with a low measurement error. Our study demonstrates the utility of femur length for age prediction in prey from macroremains in oil palm plantations, wherein most pellets are headless and R. tiomanicus is the dominant prey.

International audience; : Alveolar echinococcosis, caused by the cestode Echinococcus multilocularis, is the most serious parasitic disease for humans in Europe, with a sylvatic life cycle generally between small rodents and red foxes. General expansion of the range of E. multilocularis has been observed across Europe over the last 15years. In France, a westward spread of the known endemic areas of the parasite was described recently. For genotyping, the microsatellite EmsB was used to trace expansion in five French areas. A total of 22 EmsB profiles were identified, with five similar to those previously described in other parts of Europe. An imbalance of genetic diversity was observed between the five areas which also revealed their interconnection with the presence of common profiles, notably the two main profiles both present in all regions except one in the North. These two findings are similar to those described at the European level, highlighting transmission of the parasite by a mainland-island system. A spatio-temporal scenario of the expansion of E. multilocularis can be proposed with spread from the French historical focus in eastern France to the Lorraine, the Champagne-Ardenne and finally the North, while simultaneously another expansion has occurred from the historical focus into the West. The colonization by the parasite into the West and North areas from the historical focus was probably due to the migration of foxes several decades ago. Recent detection of the parasite in new endemic "départements" may be due to more active research rather than a recent spread of the parasite. Regarding the numerous data obtained by the different EmsB analyses, principally across Europe, centralization of all the profiles described in a public databank appears necessary in order to obtain a precise understanding of transmission of the parasite from one country to another.

International audience; Our study showed that open pastures had more small mammal burrows than fenced pastures in Tibetan pastoralist communities in 2003. This characteristic was linked to a higher prevalence of Echinococcus multilocularis in dogs and indicates that pasture type may affect E. multilocularis transmission.

出版社版, A 43-year-old Tibetan woman living in northwest Sichuan, China, confirmed to be a taeniasis carrier of Taenia solium was treated with pumpkin seeds combined with Areca nut extract in October 2009. All 20 tapeworms except one without scolex were expelled under good conditions. She was free of secondary cysticercosis within one year follow up. Although the first choice for treatment of taeniasis is still praziquantel, it may often cause serious side effect on asymptomatic cysticercosis cases to suddenly become symptomatic within a half day of the treatment. Therefore, the problems in treatment of taeniasis and/or cysticercosis in Asia are briefly overviewed, since other platyhelminthic diseases including schistosomiasis, opisthorchiasis etc. are more common and praziquantel is strongly recommended for mass treatment of these trematodiases with no idea on the co-infection with eggs of T. solium which cause asymptomatic cysticercosis.

This is an open-access article distributed under the terms of the Creative Commons Attribution License, BACKGROUND: Human alveolar echinococcocosis (AE) is a highly pathogenic zoonotic disease caused by the larval stage of the cestode E. multilocularis. Its life-cycle includes more than 40 species of small mammal intermediate hosts. Therefore, host biodiversity losses could be expected to alter transmission. Climate may also have possible impacts on E. multilocularis egg survival. We examined the distribution of human AE across two spatial scales, (i) for continental China and (ii) over the eastern edge of the Tibetan plateau. We tested the hypotheses that human disease distribution can be explained by either the biodiversity of small mammal intermediate host species, or by environmental factors such as climate or landscape characteristics. METHODOLOGY/FINDINGS: The distributions of 274 small mammal species were mapped to 967 point locations on a grid covering continental China. Land cover, elevation, monthly rainfall and temperature were mapped using remotely sensed imagery and compared to the distribution of human AE disease at continental scale and over the eastern Tibetan plateau. Infection status of 17,589 people screened by abdominal ultrasound in 2002-2008 in 94 villages of Tibetan areas of western Sichuan and Qinghai provinces was analyzed using generalized additive mixed models and related to epidemiological and environmental covariates. We found that human AE was not directly correlated with small mammal reservoir host species richness, but rather was spatially correlated with landscape features and climate which could confirm and predict human disease hotspots over a 200,000 km(2) region. CONCLUSIONS/SIGNIFICANCE: E. multilocularis transmission and resultant human disease risk was better predicted from landscape features that could support increases of small mammal host species prone to population outbreaks, rather than host species richness. We anticipate that our study may be a starting point for further research wherein landscape management could be used to predict human disease risk and for controlling this zoonotic helminthic.

International audience; During 2005-2010, we investigated Echinococcus multilocularis within fox populations in a large area in France. The parasite is much more widely distributed than hitherto thought, spreading west, with a much higher prevalence than previously reported. The parasite also is present in the large conurbation of Paris.

International audience; Since the first 2 cases observed in Southern Germany and the correct identification of a parasite at the origin of the disease by the famous scientist Rudolf Virchow in 1855, the borders of the endemic area of alveolar echinococcosis (AE) have never stopped to expand. The parasite was successively recognized in Switzerland, then in Russia, Austria and France which were long considered as the only endemic areas for the disease. Cases were disclosed in Turkey in 1939; then much attention was paid to Alaska and to Hokkaido, in Japan. The situation totally changed in 1991 after the recognition of the Chinese endemic areas by the international community of scientists. The world map was completed in the beginning of the 21st century by the identification of AE in most of the countries of central/eastern Europe and Baltic States, and by the recognition of cases in central Asia. Up to now, the disease has however never been reported in the South hemisphere and in the United Kingdom. In the mid-1950s, demonstration by Rausch and Schiller in Alaska, and by Vogel in Germany, of the distinction between 2 parasite species responsible respectively for cystic echinococcosis ("hydatid disease") and AE put an end to the long-lasting debate between the "dualists", who believed in that theory which eventually proved to be true, and the "unicists", who believed in a single species responsible for both diseases. At the end of the 20th century, molecular biology fully confirmed the "dualist" theory while adding several new species to the initially described E. granulosus; within the past decade, it also confirmed that little variation existed within E. multilocularis species, and that AE-looking infection in some intermediate animal hosts on the Tibetan plateau was indeed due to a new species, distinct from E. multilocularis, named E. shiquicus. Since the 1970s, the unique ecological interactions between the landscape, the hosts, and E. multilocularis have progressively been delineated. The important role of the rodent/lagomorph reservoir size for the maintenance of the parasite cycle has been recognized within the last 2 decades of the 20th century. And the discovery of a close relationship between high densities of small mammals and particularities in land use by agriculture/forestry has stressed the responsibility of political/economic decisions on the contamination pressure. Urbanization of foxes in Europe and Japan and the major role of dogs in China represent the new deals at the beginning of the 21st century regarding definitive hosts and prevention measures.

International audience; Concepts and developments for a new field in ecotoxicology, referred to as "landscape ecotoxicology," were proposed in the 1990s; however, to date, few studies have been developed in this emergent field. In fact, there is a strong interest in developing this area, both for renewing the concepts and tools used in ecotoxicology as well as for responding to practical issues, such as risk assessment. The aim of this study was to investigate the spatial heterogeneity of metal bioaccumulation in animals in order to identify the role of spatially explicit factors, such as landscape as well as total and extractable metal concentrations in soils. Over a smelter-impacted area, we studied the accumulation of trace metals (TMs: Cd, Pb and Zn) in invertebrates (the grove snail Cepaea sp and the glass snail Oxychilus draparnaudi) and vertebrates (the bank vole Myodes glareolus and the greater white-toothed shrew Crocidura russula). Total and CaCl(2)-extractable concentrations of TMs were measured in soils from woody patches where the animals were captured. TM concentrations in animals exhibited a high spatial heterogeneity. They increased with soil pollution and were better explained by total rather than CaCl(2)-extractable TM concentrations, except in Cepaea sp. TM levels in animals and their variations along the pollution gradient were modulated by the landscape, and this influence was species and metal specific. Median soil metal concentrations (predicted by universal kriging) were calculated in buffers of increasing size and were related to bioaccumulation. The spatial scale at which TM concentrations in animals and soils showed the strongest correlations varied between metals, species and landscapes. The potential underlying mechanisms of landscape influence (community functioning, behaviour, etc.) are discussed. Present results highlight the need for the further development of landscape ecotoxicology and multi-scale approaches, which would enhance our understanding of pollutant transfer and effects in ecosystems.

International audience; The spatial distribution of total and CaCl(2)-extracted Cd, Pb and Zn concentrations in smelter-impacted soils was investigated over a polluted site (40km(2)) in Northern France. The study was conducted on 262 soils sampled in woody habitats. Total and extracted concentrations of trace metals (TMs) rose up to 2402 and 59.5mgkg(-1) for Cd, 41 960 and 13.7mgkg(-1) for Pb, 38 760 and 143.0mgkg(-1) for Zn, respectively. The spatial dependence of both total and extracted concentrations showed a high spatial auto-correlation and ordinary kriging was used to predict soil concentrations. Investigating which variables influenced metal concentrations and their spatial distribution, we found that total concentrations mostly depended on the distance from the smelter, the wind and the organic carbon, while extracted concentrations were mainly modulated by the pH. Conditionally to those variables, other soil properties and landscape characteristics influenced both total and extracted concentrations. We conclude that total and extracted TM concentrations are governed by different processes which act at various spatial ranges: total concentrations are mainly related to input and retention of metals (large scale) whereas extracted concentrations were mainly explained by factors controlling metal solubility in soils (local scale). Spatial distributions of total and extracted TMs differed over the area, which should be considered for risk assessment. Maps of risk based on the US EPA's Eco-SSLs (for plants, invertebrates and vertebrates) were realized, showing that wildlife may be at risk but that the relevance of Eco-SSL values is questionable.

The functional response of predators to prey density variations has previously been investigated in order to understand predation patterns. However, the consequences of functional response on parasite transmission remain largely unexplored. The rodents Microtus arvalis and Arvicola terrestris are the main prey of the red fox Vulpes vulpes in eastern France. These species are intermediate and definitive hosts of the cestode Echinococcus multilocularis. We explored the dietary and contamination responses of the red fox to variations in prey density. The dietary response differed between the two prey species: no response for M. arvalis and a type III-like (sigmoidal) response for A. terrestris that shows possible interference with M. arvalis. The fox contamination response followed a type II shape (asymptotic) for both species. We conclude that fox predation is species specific and E. multilocularis transmission is likely to be regulated by a complex combination of predation and immunologic factors. These results should provide a better understanding of the biological and ecological mechanisms involved in the transmission dynamics of trophically transmitted parasites when multiple hosts are involved. The relevance of the models of parasite transmission should be enhanced if non-linear patterns are taken into account.

International audience; We investigated how host factors (species, age, gender) modulated Cd, Pb, Zn, and Cu concentrations, metallothionein levels (MTs) and their relationships in 7 sympatric small mammal species along a pollution gradient. Cd concentrations in liver and kidneys increased with age in all species. Age effect on other metals and MTs differs among species. Gender did not influence metal and MT levels except in the bank vole. Three patterns linking internal metal concentrations and MTs were observed along the gradient: a low metal accumulation with a (i) high (wood mouse) or (ii) low (bank vole) level of MTs accompanied by a slight or no increase of MTs with Cd accumulation; (iii) an elevated metal accumulation with a sharp increase of MTs (common and pygmy shrews). In risk assessment and biomonitoring perspectives, we conclude that measurements of MTs and metals might be associated because they cannot be interpreted properly when considered separately.

Corresponding author; amelie.vaniscotte@univ-fcomte.fr; International audience; We investigate the relationship between landscape heterogeneity and the spatial distribution of small mammals in two areas of Western Sichuan, China. Given a large diversity of species trapped within a large number of habitats, we first classified small mammal assemblages and then modelled the habitat of each in the space of quantitative environmental descriptors. Our original two step "classify then model" procedure is appropriate for the frequently encountered study scenario: trapping data collected in remote areas with sampling guided by expert field knowledge. In the classification step, we defined assemblages by grouping sites of similar species composition and relative densities using an expert-class-merging procedure which reduced redundancy in the habitat factor used within a multinomial logistic regression predicting species trapping probabilities. Assemblages were thus defined as mixtures of small mammal frequency distributions in discrete groups of sampled sites. In the modelling step, assemblages' habitats and environments of the two sampled areas were discriminated in the space of remotely sensed environmental descriptors. First, we compared the discrimination of assemblage/study areas by linear and non-linear forms of discriminant analysis (linear discriminant analysis versus mixture discriminant analysis) and of multiple regression (generalized linear models versus multiple adaptive regression splines). The "best" predictive modelling technique was then used to quantify the contribution of each environmental variable in discriminations of assemblages and areas. Mixtures of Gaussians provided a more efficient model of assemblage coverage in environmental space than a single Gaussian cluster model. However, non-linearity in assemblage response to environmental gradients was consistently predicted with lower deviance and misclassification error by multiple adaptive regression splines. The two study areas were mainly discriminated along vegetation indices. However, although the normalized difference vegetation index (NDVI) could discriminate forested from non-forested habitats, its power to discriminate assemblages in Maerkang, where a greater diversity of forest habitat was observed, was seen to be limited, and in this case NDVI was outperformed by the enhanced vegetation index (EVI). Our analyses highlight previously unobserved differences between the environments and small mammal communities of two fringe areas of the Tibetan plateau and suggests that a biogeographical approach is required to elucidate ecological processes in small mammal communities and to reduce extrapolation uncertainty in distribution mapping

Background Alveolar echinococcosis (AE) is a severe helminth disease affecting humans, which is caused by the fox tapeworm Echinococcus multilocularis. AE represents a serious public health issue in larger regions of China, Siberia, and other regions in Asia. In Europe, a significant increase in prevalence since the 1990s is not only affecting the historically documented endemic area north of the Alps but more recently also neighbouring regions previously not known to be endemic. The genetic diversity of the parasite population and respective distribution in Europe have now been investigated in view of generating a fine-tuned map of parasite variants occurring in Europe. This approach may serve as a model to study the parasite at a worldwide level. Methodology/Principal Findings The genetic diversity of E. multilocularis was assessed based upon the tandemly repeated microsatellite marker EmsB in association with matching fox host geographical positions. Our study demonstrated a higher genetic diversity in the endemic areas north of the Alps when compared to other areas. Conclusions/Significance The study of the spatial distribution of E. multilocularis in Europe, based on 32 genetic clusters, suggests that Europe can be considered as a unique global focus of E. multilocularis, which can be schematically drawn as a central core located in Switzerland and Jura Swabe flanked by neighbouring regions where the parasite exhibits a lower genetic diversity. The transmission of the parasite into peripheral regions is governed by a “mainland–island” system. Moreover, the presence of similar genetic profiles in both zones indicated a founder event., Author Summary Echinococcus multilocularis is a tapeworm of the red fox, which represents a considerable health threat to respectively infected humans. Main endemic areas are located in China, Siberia, and central Europe. Alarmed by an emerging or reemerging situation in Europe, the question of how the parasite gets spatially and temporally spread and transmitted becomes essential to prepare appropriate control programs. The question was tackled by using genetic data on a large sample size of E. multilocularis adult stage tapeworms, combined with geographical site location data input. The historically documented endemic area, represented by the northern Alpine arch, was shown to harbour the highest genetic richness and diversity, as compared to surrounding areas in northern and eastern Europe. The spatial and temporal spread of different E. multilocularis genotypes in Europe seems to be ruled by a founder event, linked to exportation of parasites from the central core to newly identified (western and eastern) areas or subregions, where these parasites could subsequently disseminate under geographical separation from the original foci.

The Chinese jumping mouse Eozapus setchuanus (Pousargues, 1896) is endemic to the eastern border of the Tibetan plateau in China. It belongs to the Dipodidae family (Zapodinae sub-family) (Wilson and Reeder, 2005), among which the monotypic genus Eozapus is endemic to central China (Wilson and Reeder, 2005). Only about a dozen specimens are known to have been collected and deposited in Museums (Nowak, 1999). They come from elevations of 3,000–4,000 m, and stream bank in mountainous cool forests is the putative preferred habitat described by Nowak (1999). Still now, this species is reported to be rarely collected (Sung, 1998, in Amori and Gippoliti, 2003). Almost all published information concerns small mammal inventories or checklists at the regional scale, and atlases in which the presence of E. setchuanus is reported (Zhang, 1997; Wang, 2003; Qi et al., 2004; Zhang and Hu, 2004; Liu et al., 2005; Qi et al., 2005; Smith and Xie, 2008). To the best of our knowledge, no detailed information exists on its habitat requirements, life history traits, or population status. These data are however needed since the IUCN (World Conservation Union) designates E. setchuanus as vulnerable (category VU A1c), facing a high risk of extinction in the medium-term future because of human induced forest loss and degradation (Baillie, 1996). Its status was assessed in 1996, and its population trend is unknown (Baillie, 1996). Conservation actions towards this species must be grounded on a detailed knowledge about its ecology. We report descriptive data on E. setchuanus which were collected by our research team as part of small mammal community surveys conducted in Central China between 1996 and 2005 (Giraudoux et al., 1998; Giraudoux et al., 2003; Giraudoux et al., 2006; Raoul et al., 2006). Details of trapping procedure are given by Giraudoux et al. (1998) and Raoul et al. (2006). Animals were sampled in July 1996, September 2003, June 2004, and September 2005. We compare these results with information available from the literature. Museum specimens were also used as information source. We provide information about life-history traits and habitat of E. setchuanus and present the first description of its karyotype.

International audience; Parasite requires an understanding of complex transmission systems where individual, population and environmental factors and their interactions can hardly been considered separately. Moreover, the importance of space and time in host population and parasite transmission processes is increasingly recognised. The present review illustrates how epidemiology and transmission ecology have evolved in a multidisciplinary framework to a systems approach that includes both spatial and temporal dimensions. Focusing on population processes, three significant challenges are discussed: (i) integration of landscape ecology concepts and modelling across time-space scales, (ii) development of molecular methods that permits easy parasite/host identification and process tracking (e.g. host and parasite movements), and (iii) integration of sociology methods to estimate zoonotic risk and exposure.

Background Alveolar echinococcosis (AE) presents a serious public health challenge within China. Mass screening ultrasound surveys can detect pre-symptomatic AE, but targeting areas identified from hospital records is inefficient regarding AE. Prediction of undetected or emerging hotspots would increase detection rates. Voles and lemmings of the subfamily Arvicolinae are important intermediate hosts in sylvatic transmission systems. Their populations reach high densities in productive grasslands where food and cover are abundant. Habitat availability is thought to affect arvicoline population dynamic patterns and definitive host–intermediate host interactions. Arvicoline habitat correlates with AE prevalence in Western Europe and southern Gansu Province, China. Methods and Findings Xiji County, Ningxia Hui Autonomous Region, borders southern Gansu. The aims of this study were to map AE prevalence across Xiji and test arvicoline habitat as a predictor. Land cover was mapped using remotely sensed (Landsat) imagery. Infection status of 3,205 individuals screened in 2002–2003 was related, using generalised additive mixed models, to covariates: gender; farming; ethnicity; dog ownership; water source; and areal cover of mountain pasture and lowland pasture. A Markov random field modelled additional spatial variation and uncertainty. Mountain pasture and lowland pasture were associated with below and above average AE prevalence, respectively. Conclusions Low values of the normalised difference vegetation index indicated sub-optimality of lowland pasture for grassland arvicolines. Unlike other known endemic areas, grassland arvicolines probably did not provide the principal reservoir for Echinococcus multilocularis in Xiji. This result is consistent with recent small mammal surveys reporting low arvicoline densities and high densities of hamsters, pikas and jerboas, all suitable intermediate hosts for E. multilocularis, in reforested lowland pasture. The risk of re-emergence is discussed. We recommend extending monitoring to: southern Haiyuan County, where predicted prevalence was high; southern Xiji County, where prediction uncertainty was high; and monitoring small mammal community dynamics and the infection status of dogs., Author Summary In humans, larvae of the fox tapeworm Echinococcus multilocularis typically infect the liver where metastasis, calcification and necrosis cause the zoonotic disease alveolar echinococcosis (AE). Treatment is difficult. Early detection greatly increases patient life expectancy but under-detection is a problem. Understanding the ecological conditions that elevate AE risk would help identify at-risk communities. Voles and lemmings of the subfamily Arvicolinae are important intermediate hosts in most AE endemic areas, and arvicoline habitat has been proposed as a predictor of AE risk. Using a model of spatial autocorrelation with land cover identified from satellite remote sensing imagery, we identified AE hotspots in southern Ningxia Hui Autonomous Region (NHAR), China. Hotspots were not located near optimal arvicoline habitats. Thus, non-arvicolines provide principal reservoirs in NHAR and the range of ecological conditions sustaining E. multilocularis transmission in China is greater than previously thought. We also show: social factors explain higher prevalence in females than males; dogs increase infection risk; and we argue that water source quality is important via interaction with other environmental variables. Our map of AE prevalence represents the current state-of-the-art regarding the spatial distribution of AE in southern NHAR and provides an important baseline for future monitoring programs there.

International audience; Data from two cross-sectional investigations on 7,138 subjects were used to explore risk factors of human alveolar echinococcosis (AE) in Tibetan communities. The overall human AE prevalence was 3.1% (223 of 7,138), females had a higher prevalence (3.6%, 132 of 3,713) than males (2.7%, 91 of 3,425; P = 0.011), and herdsmen had a higher prevalence (5.2%, 154 of 2,955) than farmers (1.8%, 12 of 661; P < 0.001) and urban populations (2.1%, 49 of 2,360; P < 0.001). Age in all populations, number of dogs kept, fox skin ownership in farmers, not preventing flies from landing on food in herdsmen, using open streams as drinking water sources, and playing with dogs in urban populations were statistically significant risk factors. The results suggest that AE is highly endemic in the eastern Tibetan plateau, in Sichuan Province, the role of the dog is important for human infection, and other factors associated with environmental contamination may vary according to structure and practices of communities.

An area close to the Qinghai-Tibet plateau region and subject to intensive deforestation contains a large focus of human alveolar echinococcosis while sporadic human cases occur in the Doubs region of eastern France. The current review analyses and compares epidemiological and ecological results obtained in both regions. Analysis of rodent species assemblages within quantified rural landscapes in central China and eastern France shows a significant association between host species for the pathogenic helminthEchinococcus multilocularis, with prevalences of human alveolar echinococcosis and with land area under shrubland or grassland. This suggests that at the regional scale landscape can affect human disease distribution through interaction with small mammal communities and their population dynamics. Lidicker's ROMPA hypothesis helps to explain this association and provides a novel explanation of how landscape changes may result in increased risk of a rodent-borne zoonotic disease.

Alveolar echinococcosis (AE) is an endemic zoonosis in France due to the cestode Echinococcus multilocularis. The French National Reference Centre for Alveolar Echinococcosis (CNR-EA), connected to the FrancEchino network, is responsible for recording all AE cases diagnosed in France. Administrative, epidemiological and medical information on the French AE cases may currently be considered exhaustive only on the diagnosis time. To constitute a reference data set, an information system (IS) was developed thanks to a relational database management system (MySQL language). The current data set will evolve towards a dynamic surveillance system, including follow-up data (e.g. imaging, serology) and will be connected to environmental and parasitological data relative to E. multilocularis to better understand the pathogen transmission pathway. A particularly important goal is the possible interoperability of the IS with similar European and other databases abroad; this new IS could play a supporting role in the creation of new AE registries.

アラスカ、中国、北海道、そして、フランス東部での調査結果をもとに野生動物間でのエキノコックス（多包条虫）の伝播生態について述べた。エキノコックスの伝播は、ハビタットの異質性が低く、周期的個体数変動をする感受性の高い中間宿主にとって好適なハビタットの割合が高いランドスケープでより生じやすいことや、伝播過程は宿主の生態に強く依存し、キツネの行動様式や主たる餌資源の分布などによって、感染の季節的変化を含め地域での伝播様式に違いの生じることを示した。また、異なるスケールでのランドスケープや群集の解析によるエキノコックスの伝播に関する総合的な研究の重要性について指摘した。