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International audience; In zoonotic infections, the relationships between animals and humans lead to parasitic disease with severity that ranges from mild symptoms to life-threatening conditions. In cities and their surrounding areas, this statement is truer with the overcrowding of the protagonists of the parasites' life cycle. The present study aims to investigate the distribution of a parasite, Echinococcus multilocularis, which is the causative agent of alveolar echinococcosis, using copro-sampling in historically endemic rural settlements of the eastern part of France and in newly endemic areas including urban parks and settlements surrounding Paris. Based on 2741 morphologically identified and geolocalized copro-samples, the density of fox faeces was generally higher in the surrounding settlements, except for one rural area where the faeces were at larger density downtown in the winter. Fox faeces are rare but present in urban parks. Dog faeces are concentrated in the park entrances and in the centre of the settlements. DNA was extracted for 1530 samples that were collected and identified from fox, dog, cat, stone marten and badger carnivore hosts. Echinococcus multilocularis diagnosis and host faecal tests were performed using real-time PCR. We failed to detect the parasite in the surroundings of Paris, but the parasite was found in the foxes, dogs and cats in the rural settlements and their surroundings in the historically endemic area. A spatial structuring of the carnivore stool distribution was highlighted in the present study with high densities of carnivore stools among human occupied areas within some potentially high-risk locations.

We investigate the effects of cell division and apopotosis on collective dynamics in two-dimensional epithelial tissues. Our model includes three key ingredients observed across many epithelia, namely cell-cell adhesion, cell death and a cell division process that depends on the surrounding environment. We show a rich non-equilibrium phase diagram depending on the ratio of cell death to cell division and on the adhesion strength. For large apopotosis rates, cells die out and the tissue disintegrates. As the death rate decreases, however, we show, consecutively, the existence of a gas-like phase, a gel-like phase, and a dense confluent (tissue) phase. Most striking is the observation that the tissue is self-melting through its own internal activity, ruling out the existence of any glassy phase., Comment: 9 pages, 10 figures

SUMMARYEpidemiological data from bank voles,Myodes glareolus, naturally infected by the hantavirus Puumala (PUUV) were collected by a capture–mark–recapture protocol from 2000 to 2002 in the French department of Ardennes. Four monitored trapping sites were established in two forests located in two cantons (Flize and Monthermé). We captured 912 bank voles corresponding to 557 different individuals during 8820 trapping nights for an overall trapping success of 10·34%. The average PUUV seroprevalence was 22·4%. Characteristics of the system reported in North European countries are confirmed in France. PUUV seroprevalence and abundance of rodents appeared weakly linked. Adult voles were more frequently antibody-positive, but no difference between sexes was established. Anti-PUUV seropositive voles were captured and high seroprevalence was observed from both forests, without human infection reported in Flize canton during the study. One site among the four exhibited peculiar infection dynamics, where vole weight and infection risk were negatively correlated.

Remerciements ECOFECT; International audience; In Europe, Culicoides chiopterus, Culicoides dewulfi, Culicoides obsoletus and Culicoides scoticus, which belongs to the subgenus Avaritia and Obsoletus group are the most proficient Bluetongue and Schmallenberg vectors. Within this group, correct identification based on morphological traits is difficult but essential to assess disease transmission risk. The development of new tools has revolutionized taxonomy (i.e. geometric morphometrics and molecular biology). Wing morphology is of primary importance to entomologists interested in systematics. Here, we report phenotypic differentiation patterns among the species above mentioned using a landmark-based geometric morphometric approach that efficiently identified C. chiopterus and C. dewulfi. Wing shape of the C. scoticus sample exhibited large specific variability. Based on landmarks and phylogenetic analyses (Maximum Parsimony), we suggest that Obsoletus group in Europe includes only C. obsoletus and C. scoticus. C. dewulfi and C. chiopterus are clearly excluded. Their shape seems closer to C. obsoletus that is why we suggest that only these two species should be grouped in the Obsoletus group. In addition, the concordance between phenetic clusters and phylogenies inferred from molecular data based on a fragment of the mtDNA COI gene and rDNA 28S suggests the existence of a strong signal in wing shape. These findings encourage us to use this powerful tool in taxonomic studies.

International audience; We evaluated a dog owner, participation-based, bait delivery system for the oral immunization of dogs against rabies. In a field study in a semirural area of northern Tunisia, dog owners were asked to come to temporary bait delivery sites. A total of 314 baits were given to 178 dog owners in four sites. The experimental baits used consisted of a freeze-dried core unit containing sulfadimethoxine (SDM) as a biological marker and an aromatized paraffin envelope. No vaccine was used. Preliminary tests had shown that by using a rapid commercial card test, positive SDM serum levels were detected in more than 95% of dogs up to two days after bait ingestion. During the two days following bait delivery, we visited more than 95% of all households in the study area and took blood samples from as many owned dogs as possible. Unconsumed baits were recovered and human contacts with the bait matrix were recorded. The campaign required 7.6 person-min per bait and 13.5 person-min per dog owner for providing baits, gloves, and instructions. The estimated average cost effectiveness ratio per dog accepting a bait was 1.7 US dollars. From the indications given by the dog owners and the results of the SDM test, it was concluded that 85-90% of the owned dogs in the study area had consumed a bait at least partially. Of 314 baits delivered, 78.7% were fully consumed by dogs and 4.1% were recovered during the household survey. The remaining baits (17.2%) that were not recovered were either not consumed or only partially consumed by the target dogs (3.7 baits per 100 inhabitants). These baits probably remained within the highly populated areas and were potentially accessible to other domestic animals and other nontarget species, including humans. Twenty-five unprotected human contacts with baits were recorded (1.7% of all inhabitants). Our study has demonstrated the potential of dog owner based bait delivery. This technique is simple and efficient, particularly if the human population is accustomed to mass immunization in defined centers. Before applying this method on a large scale with live vaccine loaded baits, further studies should focus on minimizing the number of human contacts with the vaccine bait, systematizing contact identification and establishing structures in ensuring proper treatment if exposure to vaccine should occur.

International audience; In many countries, the fox (Vulpes vulpes), predator of small mammals, is particularly affected by anticoagulant rodenticides such as bromadiolone due to secondary poisoning. Nevertheless, to date, no method of exposure monitoring is applicable in the field over large areas, and no toxicological data are available concerning sensitivity of foxes to bromadiolone. The aim of this work was to compare excretion kinetics of bromadiolone in fox faeces with clinical and haemostatic effects after repeated exposure to intoxicated voles. A sensitive method for the quantification of bromadiolone excretion in fox faeces and plasma was developed, using liquid chromatography combined with electrospray ionisation mass spectrometry (LC-ESI-MS). The LoD was 0.9 μg/kg and 0.15 μg/L, and the LoQ was 3.0 μg/kg and 0.5 μg/L, in faeces and in plasma, respectively. Four captive foxes were fed for 2 or 5 days with water voles (Arvicola terrestris Sherman) spiked with bromadiolone at concentrations close to those measured in the field. Faeces and blood were collected for bromadiolone titration, and blood-clotting tests were performed to monitor fox health daily during ten days and then every 3-4 days until the end of the experiment (D28). Then, after euthanasia, a complete necropsy was performed, and levels of bromadiolone residues in the liver were determined. Bromadiolone residues were detected in faeces 15 hours after the first exposure. They increased dramatically during the exposure period and then gradually decreased, but they remained detectable at the end of the experiment, i.e., 26 days after the last exposure. Bromadiolone residues in plasma showed a similar pattern but were no longer detectable 7 to 24 days after the last exposure. Two foxes presented very severe external haemorrhages, requiring the administration of the antidote vitamin-K1. Bromadiolone residues in faeces and their relationships with exposure and other directmarkers that were measured is discussed. Liver residues and the toxicity data of our study will help to interpret data from fox carcasses collected by wildlife disease surveillance networks. These findings provide a basis for programs aiming to monitor the exposure of wild fox populations to bromadiolone using non-invasive methods based on standard sampling and analysis of residues in faeces.

Leptospirosis has been so far poorly described in Cambodia and is probably underdiagnosed in the current local medical practices, although conditions to its active circulation exist in this country. Between June 2006 and July 2007, 612 patients admitted to Takeo hospital and Calmette hospital in Phnom Penh presenting clinical symptoms compatible with leptospirosis, were recruited for biological investigation of leptospirosis markers: PCR detection of bacterial DNA and serology using an Elisa-IgM test and the micro-agglutination reference test (MAT). One hundred eighty-three patients (29.9%) were found to be carrying at least one biological marker of leptospirosis, 88 (14.4%) showed an acute infection profile, evidenced by a positive PCR. The proportion of patients with an immune phase profile (15.5%) suggests former contacts with Leptospira and possible infections with little or no symptoms. Thirteen serogroups of Leptospira have been identified, with predominance of Panama, Pyrogenes and Australia, illustrating a probable wide range of animal reservoir hosts. Serogroup Icterohaemorrhagiae was found in only 4% of cases, contrasting with usual features of human leptospirosis. No significant link between infection and sex, age or occupation could be established, suggesting a permanent exposure of the population in its daily life rather than the existence of risk groups. This study, the largest conducted to date on leptospirosis in Cambodia, confirms the importance of this zoonotic disease, that must be considered a real public health issue in this country.

International audience; The zoonotic agent of bovine tuberculosis (bTB), Mycobacterium bovis, can be transmitted between domestic and wild animals, threatening wildlife populations and control programs for bTB in cattle. In Corsica, a French Mediterranean island where domestic and wild species have close interactions, bTB cases have been reported in cattle, pigs, and wild boar. Moreover, genotypes of M. bovis found in wild and domestic animals from the same area were identical. These data strongly suggest that wild and domestic animals are associated in an epidemiologic bTB-transmission cycle. More investigations are needed, not only to understand the role played by each species in order to implement appropriate control measures, but also to assess the risk of transmission to humans.

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.

National audience

International audience; This study evaluated the impact of biological and environmental factors on the infection of red foxes (Vulpes vulpes) by Echinococcus multilocularis in an endemic area of north-east France. From January 2004 to April 2006, 127 foxes were examined for E. multilocularis and their stomach contents analysed. The effect of year, season, age, sex and urbanisation level on E. multilocularis presence was estimated using a General Linear Model (GLM) with logit link, (i.e. logistic regression). Urbanisation level was the only influencing factor, with a decreasing gradient from rural [54%, CI 95% (40-68)] to peri-urban [31%, CI 95% (15-52)] and urban area [4%, CI 95% (0.7-15)]. The consumption of Arvicola terrestris and Microtus sp., grassland species, the main presumed intermediate hosts of E. multilocularis, was studied by the same approach. The two species were consumed less in the urban area and more in autumn than in spring. Anthropogenic food consumption was linked to urbanisation and to age. The frequency of anthropogenic food consumption decreased in the rural area. A global model explaining the presence of E. multilocularis and including urbanisation level and diet was then elaborated. Independently of urbanisation, there was a suggestion of less E. multilocularis infection with anthropogenic food consumption. Red foxes consuming Microtus sp. and A. terrestris had higher worm burden than those that did not. The results suggest that the decreasing gradient observed from rural to urban area is linked to behaviour and feeding habits.

International audience; 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.

Alveolar Echinococcosis is a lethal zoonosis transmitted to humans by the ingestion of eggs of the tænia Echinococcus multilocularis. The cycle of the parasite needs a carnivore as definitive host (mainly the red fox) and the common and water voles (Microtus arvalis and Arvicola terrestris) as intermediate hosts. Since 20 years, the more and more common observations of urban foxes gave rise to many questions about the possible increased risk of transmission to man due to the proximity of foxes. Recent studies showed the presence of E. multilocularis in urban foxes with variable prevalence. However, the conditions of the development of this parasite in the urbanized area are few documented. Work presented here proposes to improve comprehension of the cycle of E. multilocularis in such urbanized area. A monitoring of the red fox infection by collection of road kills or trapped animals highlighted a "rural to urban" decreasing gradient of infection. Along this gradient, different habitats were regularly sampled; this study showed the importance for the red fox of the availability of Microtus sp. in waste land landscape. The study of the adaptation of its diet by red fox to the variations of rodents densities showed that the Microtus sp. was highly consumed even when it was poorly represented in the field whereas in peri-urban area, A. terrestris,is consumed according to its availability. Taking in account the availability of rodents on the scale of the city, it was shown that the consumption of intermediate hosts is more important in rural area than in urban area and that the rural diet exhibits a predominance of Microtus sp. versus A. terrestris whereas these differences are lacking in urban area. The distribution of faeces of the red fox appeared correlated with the densities of Microtus sp and A. terrestris, underlining the possibilities of closing the parasitic cycle whatever the urbanization level. Lastly, the study of foxes movements using GPS collars has allowed to observe various types of behaviours which could induce a modulation in the space dynamics of the urban transmission of the parasite based on the stability of the local red fox populations.; L'Echinococcose Alveolaire est une zoonose mortelle transmise a l'Homme par l'ingestion des oeufs du tænia Echinococcus multilocularis. Le cycle du parasite fait intervenir un carnivore comme hote definitif (principalement le renard roux) et des campagnols prairiaux (Microtus arvalis et Arvicola terrestris) comme hotes intermediaires. Depuis une vingtaine d'annees, les observations de plus en plus frequentes de renards urbains ont suscite de nombreuses questions sur l'augmentation du risque de contamination humaine a cause de cette proximite des renards. Des etudes recentes ont montre la presence d'E. multilocularis chez le renard urbain avec des prevalences tres variables. Cependant, les conditions du developpement de ce parasite dans les milieux urbanises sont peu documentees. Les travaux presentes proposent d'ameliorer la comprehension du cycle d'E. multilocularis dans de tels milieux. Un suivi de l'infection vulpine par collecte de cadavres a mis en evidence un gradient d'infection decroissant du milieu rural au milieu urbain. Le long de ce gradient, differents milieux ont ete regulierement echantillonnes et ont montre l'importance pour le renard roux de la disponibilite en Microtus sp. dans les milieux friches. L'etude de la reponse alimentaire du renard roux aux variations de densites de rongeurs a montre que Microtus sp. etait fortement consomme meme lorsqu'il etait faiblement present sur le terrain alors que A. terrestris, en milieu peri-urbain, est consomme selon sa disponibilite. L'etude de la disponibilite en rongeurs a l'echelle de la ville montre que la consommation en hotes intermediaires est plus importante en milieu rural qu'en milieu urbain et que le regime alimentaire rural se caracterise par une predominance de Microtus sp. par rapport a A. terrestris alors que ces differences sont pas presentes en milieu urbain. La repartition des feces de renard roux est correlee aux densites de Microtus sp et d'A. terrestris, soulignant les possibilites d'existence du cycle parasitaire quel que soit le niveau d'urbanisation. Enfin, l'etude de trajectoires de renards par utilisation de colliers GPS a permis d'observer differents types de comportements individuels qui pourraient entrainer une modulation de la dynamique spatiale de la transmission urbaine du parasite basee sur la stabilite des populations vulpines.

L’accroissement des effectifs de sangliers sauvages a augmenté le risque que des infections d’importance économique et zoonosique majeure persistent dans leurs populations ou soient transmises aux animaux domestiques et à l’homme. L’épidémiosurveillance de ces infections est fondée sur le fonctionnement continu du réseau de surveillance des causes de mortalité du gibier (SAGIR) et sur un programme national de surveillance sérologique d’animaux tués à la chasse, complété par des enquêtes départementales répondant à des problématiques locales. Alors que la peste porcine classique reste cantonnée au Nord-Est de la France, les populations de sangliers françaises sont très largement infectées par Brucella suis biovar 2. Une cinquantaine d’élevages de porcs en plein air ont ainsi été contaminés depuis 1993. En revanche, un seul élevage plein air a été contaminé par le virus de la maladie d’Aujeszky qui circule à bas bruit chez les sangliers de certains départements et infecte parfois des chiens de chasse. Le sanglier a été aussi responsable chez l’homme des cas de trichinellose et de deux cas, en 2004 et 2005, et de brucellose chez des chasseurs. Il a également été trouvé porteur de Mycobactérium bovis, mais son rôle dans l'épidémiologie de la tuberculose bovine est encore mal connu. Des mesures de gestion sanitaire sont actuellement prises en France pour éviter le développement de ces maladies chez le sanglier et leur transmission aux animaux domestiques et à l’Homme.

International audience; The tapeworm Echinococcus multilocularis is dependent upon foxes and microtine rodents to complete its life cycle and is a parasite of public health importance causing the fatal zoonotic disease alveolar echinococcosis (AE). Concerns that AE could be in emergence in Europe have arisen from recent studies. In France, a monitoring survey led to the collection of 2813 georeferenced faecal samples of which 82 have been diagnosed positive for the presence of the parasite. A geographically weighted logistic regression was used to assess potential spatial variation in the effect of putative environmental risk variables. Landscape and climatic variables were expected to play a role in epidemiological factors. The results showed no significant spatial heterogeneity. This suggests a constant prevalence across the study area. The parasite is now identified in regions where it was formerly unknown, outside of traditional endemic areas.

International audience; This paper describes the role of fox population level on Echinococcus multilocularis infection in foxes in a highly endemic area in eastern France. Fox population level was monitored by spotlight survey at Le Souillot from 1989 to 2000, and from 1992 to 2000 at Chemin, a control site located in a low endemic area. The infection level of the fox population was estimated at Le Souillot from winter 1995 to winter 1999 using a coproantigen ELISA performed on faeces collected in the field. Population biomass of intermediate hosts (Microtus arvalis and Arvicola terrestris) was monitored using index methods from 1995 to 1999. At Le Souillot, a significant decline in the fox population level was recorded after spring 1997 (P

International audience; The aim of this review is to discuss the situation of alveolar echinococcosis in France, in the light of the current knowledge on its transmission patterns in the world, especially Europe. An important risk of higher contamination of the rural environment may be suspected from newly reported cases of infected foxes or voles in several countries where the disease was not found before. Furthermore, the increase of prevalence rate in foxes in Bade-Würtemberg (Germany) and Franche-Comté (France), traditionally endemic, is also in support of this new trend. Urban foxes and the spreading of infected foxes to cities may also be the cause of the extension to urban and suburban areas of a disease which was believed to be limited to rural areas. The setting up of an epidemiosurveillance system for fox (dog, cat) populations is currently in progress. It will be grounded on coprotests (ELISA, PCR) for the detection of E. multilocularis material in definitive hosts faeces and on sampling based on the multiscale analysis of the characteristics of landscapes favourable to transmission. A register of human cases has been established at the European level (WHO collaborative centre of the University of Franche-Comté and University of Ulm and Hohenheim). Unfortunately, the evolution of the parasite distribution and of the risks of exposure in France is unrecognised. Progress in surveillance and prevention could be expected if health authorities would attribute higher priority to this disease.

Prevalence of Feline Immunodeficiency Virus (FIV) infection was measured during 6 consecutive years in a natural rural population of domestic cats. Sex, age, weight, origin, group size and presence of antibodies to FIV were recorded for each sampled cat. Logistic regressions were used to estimate the influence of the recorded parameters on infection. FIV prevalence rates are as high as 19·6% in the total population, and do not statistically change between years, after controlling for changes in samples' age structure. FIV infection is characterized by risk factors linked to aggressive behaviour: old mature male adults having dispersed are more likely to be infected. A study of the cats group size and of the spatial distribution of infected individuals indicates the absence of infection clusters in males, and suggests the importance of roaming in the spreading of FIV. In conclusion, FIV infection spreads, with low contagiousness, mainly between particularly aggressive individuals, and the virus is endemic in this population.

Background Since 1954, there have been in excess of 800 cases of rabies as a result of European Bat Lyssaviruses types 1 and 2 (EBLV-1, EBLV-2) infection, mainly in Serotine and Myotis bats respectively. These viruses have rarely been reported to infect humans and terrestrial mammals, as the only exceptions are sheep in Denmark, a stone marten in Germany and a cat in France. The purpose of this study was to investigate the susceptibility of foxes to EBLVs using silver foxes (Vulpes vulpes) as a model. Results Our experimental studies have shown that the susceptibility of foxes to EBLVs is low by the intramuscular (IM) route, however, animals were sensitive to intracranial (IC) inoculation. Mortality was 100% for both EBLV-1 (~4.5 logs) and EBLV-2 (~3.0 logs) delivered by the IC route. Virus dissemination and inflammatory infiltrate in the brain were demonstrated but virus specific neutralising antibody (VNA) was limited (log(ED50) = 0.24–2.23 and 0.95–2.39 respectively for specific EBLV-1 and EBLV-2). Foxes were also susceptible, at a low level, to peripheral (IM) infection (~3.0 logs) with EBLV-1 but not EBLV-2. Three out of 21 (14.3%) foxes developed clinical signs between 14 and 24 days post-EBLV-1 infection. None of the animals given EBLV-2 developed clinical disease. Conclusion These data suggest that the chance of a EBLV spill-over from bat to fox is low, but with a greater probability for EBLV-1 than for EBLV-2 and that foxes seem to be able to clear the virus before it reaches the brain and cause a lethal infection.