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Depuis quelques années, les ceintures et autres coulées vertes envahissent les villes et leurs abords, ramenant de la biodiversité dans des lieux où elle avait longtemps été négligée, voire combattue. S’il est agréable de vivre dans un tel environnement, et de le partager avec nos compagnons domestiques et des animaux sauvages, il faut avoir conscience que cela signifie aussi accepter de côtoyer les microbes dont ces derniers sont les hôtes.Or, la gamme d’organismes pathogènes qu’ils hébergent est très large, et certains sont susceptibles de passer à l’être humain, provoquant des maladies appelées zoonoses. L’une des plus célèbres est la maladie de Lyme, causée par une bactérie et propagée par les tiques. Mais d’autres zoonoses, beaucoup plus rares, sont moins connues. Elles n’en sont pas moins graves.C’est le cas des échinococcoses provoquées par les échinocoques, des vers plats parasites qui peuvent être propagés par les renards, certains rongeurs, voire nos chiens et chats domestiques. De quoi s’agit-il exactement, et comment s’en protéger ?

Additional file 1: Figure S1. Total number of foxes naturally infected with E. multilocularis tested by intestinal scraping technique (IST). The positive animals were stratified according to the worm burden as recommended by the World Health Organization (WHO). +: 1–5 worms; ++: >5–50 worms; +++: >50–1000 worms; ++++: >1000 worms. Figure S2. Alignment of the Cox1 nucleotide sequences of isolates from Brandenburg and North Rhine-Westphalia and the reference sequence AB018440. The Cox1 gene is shown (yellow bar). The black bars represent the position of the SNPs in the sequences of the parasite isolates compared to the consensus sequence of all samples investigated in this work. Figure S3. Dendrogram derived from the Cox1 gene data of the consensus sequence of all isolates identified in this work, the sequences with the respective SNPs and the sequences taken from Nakao et al. [62]. Bootstrap values (%) are shown on the branches. Figure S4. Alignment of the Nad1 nucleotide sequences of isolates from Brandenburg and North Rhine-Westphalia and the reference sequence AB018440. The Nad1 gene is shown (yellow bar). The black bars represent the position of the SNPs in the sequences of the parasite isolates compared to the consensus sequence of all samples investigated in this work. Figure S5. Dendrogram derived from the Nad1 gene data of the consensus sequence of all isolates identified in this work, the sequences with the respective SNPs and the sequences taken from Nakao et al. [62]. Bootstrap values (%) are shown on the branches. Figure S6. Alignment of the ATP6 nucleotide sequences of isolates from Brandenburg and North Rhine-Westphalia and the reference sequence AB018440. The ATP6 gene is shown (yellow bar). The black bars represent the position of the SNPs in the sequences of the parasite isolates compared to the consensus sequence of all samples investigated in this work. Figure S7. Dendrogram derived from the ATP6 gene data of the consensus sequence of all isolates identified in this work, the sequences with the respective SNPs and the sequences taken from Nakao et al. [62]. Bootstrap values (%) are shown on the branches. Figure S8. Dendrogram derived from the concatenated (atp6, cox1, nd1) data of the consensus DNA sequences of all isolates identified in this work, the respective SNPs and the sequences taken from Nakao et al. [62]. Bootstrap values (%) are shown on the branches.

Echinococcoses require the involvement of specialists from nearly all disciplines; standardization of the terminology used in the field is thus crucial. To harmonize echinococcosis terminology on sound scientific and linguistic grounds, the World Association of Echinococcosis launched a Formal Consensus process. Under the coordination of a Steering and Writing Group (SWG), a Consultation and Rating Group (CRG) had the main missions of (1) providing input on the list of terms drafted by the SWG, taking into account the available literature and the participants' experience; and (2) providing independent rating on all debated terms submitted to vote. The mission of the Reading and Review Group (RRG) was to give an opinion about the recommendation paper in terms of readability, acceptability and applicability. The main achievements of this process were: (1) an update of the current nomenclature of Echinococcus spp.; (2) an agreement on three names of diseases due to Echinococcus spp.: Cystic Echinococcosis (CE), Alveolar Echinococcosis (AE) and Neotropical Echinococcosis (NE), and the exclusion of all other names; (3) an agreement on the restricted use of the adjective “hydatid” to refer to the cyst and fluid due to E. granulosus sensu lato; and (4) an agreement on a standardized description of the surgical operations for CE, according to the “Approach, cyst Opening, Resection, and Completeness” (AORC) framework. In addition, 95 “approved” and 60 “rejected” terms were listed. The recommendations provided in this paper will be applicable to scientific publications in English and communication with professionals. They will be used for translation into other languages spoken in endemic countries. © D.A. Vuitton et al., published by EDP Sciences, 2020, The Steering and Writing Committee would like to thank in particular Dr. Francesca Tamarozzi for her involvement in the fruitful exchanges between the WAE and the WHO-IWGE, and for her very helpful revision of the final manuscript.

National audience; Echinococcus multilocularis (Em) est un cestode Responsable de l’échinococcose alvéolaire.Les carnivores hôtes définitifs abritent les vers adultes qui produisent des œufs (formes infectantes des rongeurs et de l’homme) répandus dans l’environnement avec les fèces. L’utilisation de marqueurs moléculaires permet d’identifier et de suivre des variants génétiques parasitaires dans la population vulpine. Cependant l’ADN est souvent extrait des vers adultes impliquant un piégeage et une autopsie pratiqués sur les carnivores. Nous avons développé une approche non invasive qui a consisté à typer un à un les œufs contenus dans des fèces de renard, chien et chat testées positives par une qPCR spécifique d’Em et à étudier leur variabilité génétique à l'aide du microsatellite EmsB. Des œufs d’Em ont été isolés par flottaison dans 1/3 (31/96) des fèces de carnivores (70 de renard, 15 de chien, 6 de chat) collectées dans un village situé en zone d’endémie de l’échinococcose alvéolaire (département du Doubs) et testées positives par la qPCR. En analyses préliminaires, 18 œufs isolés `a partir de 6 fèces de renard (1 à 4 œufs par fèces) présentaient 3 profils EmsB différents notifiés précédemment dans la région d’étude, en France et en Europe. Ces données confirment que la présence d’ADN du parasite ne présume pas de la présence des œufs. Une confirmation par flottaison est alors nécessairepour estimer le risque infectieux. Dans cette approche non invasive, l’isolement individuel des œufs a permis de mettre en évidence pour la première fois des profils EmsB à partir des fèces.

International audience; In the late 1980s, a “large” focus of human alveolar echinococcosis (AE) was described in Zhang and Min counties, south Gansu, western China, with 71% of the families keeping dogs and a 4-23% of E. multilocularis prevalence in dogs (Craig et al., 1992). Multidisciplinary studies were carried out there from 1994 to 1997 and found 4.1% human AE prevalence, with peaks of 15% in some villages (Craig et al., 2000). AE was nearly 3 times higher in villages situated where areas of shrub and grassland were larger. However, populations of dogs and probably red foxes had collapsed by the early 1990s, for example only one family was found to still own a dog in Cao Tan valley. Therefore, it was inferred that human AE cases detected had been infected before the definitive host populations collapsed. From those observations, a robust transmission model involving landscape characteristics, climate, small mammal and definitive host population dynamics, was proposed which proved to be generally applicable in endemic areas of Europe as well as in most parts of China and Central Asia (Giraudoux et al., 2003; Giraudoux et al., 2013a; Giraudoux et al., 2013b). The question of the continued lack of infected definitive hosts and thus continued low/no transmission, was however pending, since Zhang and Min counties are geographically situated close to the eastern edge of the Tibetan plateau, known to be a large stable zoonotic area for AE from where reinfection is possible (dog trade, fox movements, etc.).Here we report the analysis of results obtained from a human ultrasound screening carried out in the same area in 2005-2006, and from a dog survey in May 2015 to investigate possible re-establishment of transmission after collapse of definitive host populations. No evidence was found of recent AE infection in humans in 2005-2006. Although the dog population had recovered and that forest protection and the reforestation of some areas may favor fox population growth, no evidence of infection in owned dogs was found in 2015. This suggests a sustained largely environmental elimination of E. multilocularis transmission in this area, despite the relative vicinity of the large active foci of the eastern Tibetan plateau. The history and the socio-ecological conditions for the sustainability of continued environmental control will be discussed.

International audience; In the late 1980s, a “large” focus of human alveolar echinococcosis (AE) was described in Zhang and Min counties, south Gansu, western China, with 71% of the families keeping dogs and a 4-23% of E. multilocularis prevalence in dogs (Craig et al., 1992). Multidisciplinary studies were carried out there from 1994 to 1997 and found 4.1% human AE prevalence, with peaks of 15% in some villages (Craig et al., 2000). AE was nearly 3 times higher in villages situated where areas of shrub and grassland were larger. However, populations of dogs and probably red foxes had collapsed by the early 1990s, for example only one family was found to still own a dog in Cao Tan valley. Therefore, it was inferred that human AE cases detected had been infected before the definitive host populations collapsed. From those observations, a robust transmission model involving landscape characteristics, climate, small mammal and definitive host population dynamics, was proposed which proved to be generally applicable in endemic areas of Europe as well as in most parts of China and Central Asia (Giraudoux et al., 2003; Giraudoux et al., 2013a; Giraudoux et al., 2013b). The question of the continued lack of infected definitive hosts and thus continued low/no transmission, was however pending, since Zhang and Min counties are geographically situated close to the eastern edge of the Tibetan plateau, known to be a large stable zoonotic area for AE from where reinfection is possible (dog trade, fox movements, etc.).Here we report the analysis of results obtained from a human ultrasound screening carried out in the same area in 2005-2006, and from a dog survey in May 2015 to investigate possible re-establishment of transmission after collapse of definitive host populations. No evidence was found of recent AE infection in humans in 2005-2006. Although the dog population had recovered and that forest protection and the reforestation of some areas may favor fox population growth, no evidence of infection in owned dogs was found in 2015. This suggests a sustained largely environmental elimination of E. multilocularis transmission in this area, despite the relative vicinity of the large active foci of the eastern Tibetan plateau. The history and the socio-ecological conditions for the sustainability of continued environmental control will be discussed.

International audience; Trophic interactions, eg predation and herbivory, are one of the main biotic interactions driving the composition and functioning of terrestrial and aquatic food webs as they sustain energy and matter flows among organisms. The relationship between a resource availability and its consumption rate by a predator or herbivore, the functional response, is complex since often non-linear in shape and likely to depend upon the availability of other resources. Trophic interactions also nest the transmission of a large variety of multi-hosts parasites (ie trophically-transmitted parasites, TTP) within food webs. Moreover, the capacity to acquire, develop and transmit a parasite, called competence, vary among host species. The use of mathematical approaches, such as mechanistic dynamic models, to explore the transmission dynamics of TTP have often ignore the complexity of functional response and the variation in host competence. However, a prerequisite for understanding and modeling the ecology of TTP is to identify hosts species that are involved in transmission, ie the consumption of which ensures the parasite to step from the larval to the adult stage. This translates into the simple question “who is eating whom?”. Traditional techniques for investigating feces or stomach content based on macro- or microscopic identification of food remains fail to achieve fine taxonomic resolution identification of ingested items. Recently, DNA-based techniques such as metabarcoding have arisen as a powerful approach for the simultaneous taxonomic identification of several food items in feces or stomach content with high taxonomic resolution.We built a “one predator-two prey” eco-epidemiological model using a system of ordinary differential equations which allows for complex predation patterns. Using parameters related to Echinococcus multilocularis transmission in wildlife in Eastern France, we analyzed to what extent variations in prey diversity, total density and competence to transmit the parasite impact the basic reproductive number R0, which is a measure of disease outbreak risk. In parallel, we developed a molecular metabarcoding approach to investigate the diet of dog and red fox in rural settings of Eastern France, Gansu and Kyrgyzstan where E. multilocularis is endemic. Preliminary results, advantages and limitations, as well as perspectives of these recent developments will be presented.