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Les articles de Marion Vittecoq
de Pilar Alda, Juliette Langand, Dominique Faugère, Antonio A. Vázquez, Elodie Chapuis, Marion Vittecoq, Thierry De Meeûs, Sylvie Hurtrez-Boussès
In International Journal for Parasitology, (en ligne) (July, 2026), 104923
En ligne : www.sciencedirect.com[...]
Calicophoron daubneyi is an emerging rumen fluke of ruminants whose prevalence and geographic range have increased markedly across Western Europe over recent decades. Despite its growing veterinary importance, population-level genetic studies of this trematode have been hampered by the absence of suitable multilocus markers, with previous work relying on mitochondrial or ribosomal sequences that provide limited resolution for epidemiological inference. In this study, we developed and validated the first panel of polymorphic microsatellite markers for C. daubneyi and applied them to assess genetic diversity, clonality, and population structure in natural populations from the eastern French Pyrenees. Using Illumina-based genomic sequencing, we isolated 16 candidate loci, of which 10 robust and polymorphic microsatellites were retained after stringent quality filtering. We used these markers to genotype 187 adult parasites collected from cattle originating from seven localities spanning a maximum pairwise distance of approximately 50 km. Analyses explicitly accounted for the strong clonal amplification characteristic of trematode life cycles. We observed high levels of genetic diversity and a pronounced but variable clonal signal among sites. After attempting to correct for clonality and null alleles, genetic differentiation among populations was low and no significant isolation by distance was detected, consistent with substantial genetic exchange occurring at the regional spatial scale examined. These findings suggest that definitive host movement contributes importantly in shaping parasite gene flow within this interconnected livestock system. By providing the first validated microsatellite toolkit and baseline population-genetic data for C. daubneyi, this study establishes a foundation for future molecular epidemiological investigations of transmission dynamics, host–parasite interactions, and parasite dispersal in European livestock systems.
de Guilhem Conquet, Karen D. McCoy, Marion Vittecoq, Carole Leray, Charly Souc, Marie Noëlle Didelot, Chrislène Laurens, Lokman Galal, Julio A. Benavides, Sylvain Godreuil, et al.
In Science of The Total Environment, 1029 (May, 2026), 181695
En ligne : www.sciencedirect.com[...]
Wildlife is frequently reported as a host of antimicrobial resistant bacteria (AMR), often reflecting anthropogenic contamination. Among them, carbapenemase-producing Enterobacteriaceae (CPE) are one of the most worrying for human health. This study investigated the carriage of CPE in yellow-legged gull chicks (Larus michahellis) from a breeding colony of southern France, where CPE have already been detected, and compared these bacterial strains with isolates from humans hospitalized in Montpellier University Hospital, France. Cloacal swabs from 112 chicks revealed a high CPE carriage rate (12 isolates carried by 10 gulls; 8.9%). Detected species included Escherichia coli (n = 3), Citrobacter portucalensis (n = 1) and members of Enterobacter cloacae complex (n = 8). Whole-genome sequencing revealed that 8/12 isolates produced IMI-type carbapenemases (IMI-4 and NMC-A) inserted within EcloIMEX integrative elements, and 4/12 produced OXA-48 located in IncL plasmids. Human and avian CPE isolates did not have common sequences types, although they harbored identical resistance structures (EcloIMEX-1). Some OXA-48-producing E. coli isolates belonged to high-risk human-associated genotypes (ST10, ST648), confirming the potential AMR transmission to gulls via anthropic activities. Conversely, the predominance of IMI-type carbapenemases, typically associated with aquatic environments and rare in clinical settings, suggests that gulls may also carry multidrug resistant bacteria of environmental origin. Positioned at the interface between aquatic ecosystems and human-impacted areas, gulls could contribute to the dissemination of these pathogens beyond their primary reservoirs. These findings highlight the need to integrate wildlife into One Health surveillance frameworks, not only as indicators of anthropogenic AMR but also as potential sentinels of emerging resistance threats.Detection of a Merbecovirus with potential ACE2 usage in France
de Océane Rieu, Stéphane Descorps-Declère, Anaïs Dufau, Jordan Meliani, Lionel Brazier, Marion Vittecoq, Carole Leray, Anthony Olivier, Illich Mombo, Frederic Thomas, et al.
In Emerging Microbes & Infections, (en ligne) (April, 2026), 2651469
En ligne : www.tandfonline.com[...]
A novel Merbecovirus, designated Cam-2023, has been identified in Pipistrellus pipistrellus in France through non-invasive surveillance. Phylogenetic analysis demonstrates that Cam-2023 belongs to a Merbecovirus clade previously associated with ACE2 usage in closely related viruses detected in the Netherlands and Russia. While the receptor usage of Cam-2023 remains to be functionally validated, sequence similarities within the Spike protein, particularly the receptor-binding domain, suggest a putative association with a Merbecovirus clade previously associated with ACE2 usage. This discovery broadens the known host diversity of this lineage and extends its geographical range to Western Europe. Our findings highlight the importance of continuous surveillance in European bat populations to better characterize the distribution and zoonotic potential of such high-risk coronaviruses.
de Leslie-Anne Merleau, Olivier Lourdais, Anthony Olivier, Marion Vittecoq, Fabrice Alliot, Sira Traore, Carole Leray, Aurélie Goutte
In Peer Community Journal, 6 (March, 2026)
En ligne : peercommunityjournal.org[...]
Freshwater ecosystems constitute major sinks for organic contaminants, increasing anthropogenic pressures and threatening the unique biodiversity they harbour. In addition to persistent legacy compounds, such as polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs), various pollutants are less persistent but are chronically released, including polycyclic aromatic hydrocarbons (PAHs), phthalate diesters (PAEs), pyrethroid pesticides, and insect repellent. Heretofore, these pollutants have received insufficient attention in freshwater reptiles, considering their potential to trigger detrimental effects on organisms. During two years (2019 and 2020), we quantified plasma levels of 46 compounds from 7 chemical families in two monitored populations of the protected European pond turtle (Emys orbicularis) in the Camargue wetland, France. PAHs and PAEs were found predominantly and concomitantly, with similar occurrences and levels in the two populations. We observed similar inter-annual variations in PAHs and PAEs with differences between males and females, highlighting the need for a better assessment of the role of sex in the exposure pathway and the toxicokinetics of contaminants, especially in turtles. The negative relationship between PAH levels and age, as well as the high intra-individual variation in levels of both contaminant families, provides further evidence of limited bioaccumulation of these pollutants in the blood of E. orbicularis. This could be explained by the metabolic biotransformation of parent compounds, highlighting the need to quantify the levels of PAH metabolites and phthalate monoesters. Finally, our work underscores the importance of long-term monitoring to better determine the vulnerability of turtle populations already exposed to a wide range of contaminants.
de Florence Nono Almeida, Carole Leray, Magali Albignac, Marion Vittecoq, Karen D. McCoy, Alexandra ter Halle
In Journal of Hazardous Materials, 501 (January, 2026), 140658
En ligne : www.sciencedirect.com[...]
As plastic production continues to rise and waste accumulates, animal species across the planet are being increasingly exposed. However, the fate of plastics within the vertebrate body, and particularly of small microplastics (SMPs, 10–1000 µm), remains largely unknown due to challenges in reliably quantifying their loads. To address this gap, we developed a method based on pyrolysis gas chromatography coupled with tandem mass spectrometry (Py-GC/MS-MS) to quantify SMPs in the Yellow-legged Gull (Larus michahellis), an opportunistic seabird highly exposed to plastic pollution. Five gull carcasses were necropsied under controlled conditions, isolating four organs of the gastrointestinal tract. Sample preparation was undertaken in seven steps, including a potassium hydroxide digestion. Interference from lipids in quantifying polyethylene (PE), a recognized problem for this type of quantification, was addressed by selecting markers with carbon atom chains longer than the aliphatic chains of common lipids (i.e., >22 atoms), enabling us to effectively distinguish PE from biological matrix components. The use of long markers for PE raised the limit of quantification (LOQ) to 50 µg/g, while the LOQs for PMMA (poly(methyl methacrylate)), PP (polypropylene), and PS (polystyrene) were 1 µg/g. For PET (polyethylene terephthalate), the LOQ was 10 µg/g due to the relatively high level of airborne contamination in negative controls. Using this method, microplastic concentrations in gull digestive tissues was found to range over several 100 µg/g dry weight, with one individual showing particularly high exposure to PS and PE. Our method enables a reliable quantification of microplastics and provides a basis for analyzing their impacts on vertebrates.Spatiotemporal Dynamics of Blood Parasite Infections and Impacts on Avian Health and Reproduction
de Marie Buysse, Mathilde Ollagnier, Charly Souc, Marjorie Bruley, Thomas Blanchon, Carole Leray, Marion Vittecoq, Karen D. McCoy
In Molecular Ecology, (en ligne) (December, 2025), e70178
En ligne : onlinelibrary.wiley.com[...]
Parasitic infections are ubiquitous in nature, but their consequences are often difficult to evaluate in wildlife. This is particularly the case for chronic infections for which fitness impacts can be subtle or confounded with other intrinsic and extrinsic factors. Infections by Babesia (Apicomplexa, Piroplasmidae) are widespread in wildlife, but little is known about their impacts on host health. Here, we evaluated the dynamics and possible fitness consequences of infection by Babesia sp. YLG, a recently described parasite infecting yellow-legged gulls (Larus michahellis). Using a qPCR assay developed for Babesia sp. YLG, we found that prevalence was much higher in chicks compared with adults. In chicks, infection depended on the colony and was tightly related to nest infestation by the tick vector Ornithodoros (Alectorobius) maritimus; this was not the case for adult birds. Infection intensities changed over time in chicks, increasing up to approximately 37 days old and then declining. Infection was associated with reduced body condition and fledging success for adults. In chicks, infection was significantly linked to reduced growth rates, even after accounting for the additive effect of ticks. However, no relationship was detected between infection and fledging date, migration strategy or flight distances measured on a subset of GPS-tagged juvenile birds. Through its subtle effects on fitness and reproductive success, infection by Babesia sp. YLG may have significant consequences for host demography and work focused on long-term dynamics is now called for to better understand how this parasite may shape the ecology and evolution of seabird populations.High prevalence and diversity of alphacoronaviruses in bats in Southern France
de Océane Rieu, Anaïs Dufau, Jordan Meliani, Lionel Brazier, Marion Vittecoq, Carole Leray, Anthony Olivier, Emmanuel Cosson, Frederic Thomas, Eric Leroy, et al.
In EcoHealth, (en ligne) (August, 2025)
En ligne : doi.org[...]
Zoonotic diseases are increasingly affecting global health, making it crucial to understand viral dynamics in wildlife reservoirs like bats. Bats are well-established coronavirus reservoirs, and their proximity to human habitats in France raises concerns about zoonotic transmission. This study investigates the prevalence, diversity, and phylogenetic relationships of coronaviruses in bats from the Camargue and Eastern Provence, two ecologically distinct regions. A total of 785 bat guano samples were collected non-invasively, with 154 (19.6%) testing positive for coronavirus RNA, among the highest infection rates observed in European studies. Camargue samples were entirely from Pipistrellus bats, with a prevalence of 20.1%, while Provence showed greater genus diversity and prevalence ranging from 1.3% to 35.6%. Phylogenetic analysis identified Alphacoronaviruses in four subgenera: Nyctacovirus, Myotacovirus, Decacovirus, and Minunacovirus, alongside unclassified sequences. No coronavirus related to human-infecting strains (e.g., HCoV-229E) was detected. However, the combination of high prevalence, proximity to humans, and potential for host-switching led to the investigation of coronavirus infection in bats, a topic with limited data in France. These findings highlight the ecological role of bats and the importance of continuous viral monitoring, filling a gap in knowledge about coronavirus circulation in European bat populations.Presence and potential impact of anthropogenic nesting materials on a colonial breeding waterbird
de Hugo Rafael Soares Ferreira, Ana C. Hadden, Jocelyn Champagnon, Tamar Lok, Marion Vittecoq, José A. Alves
In Science of The Total Environment, 964 (February, 2025), 178588
En ligne : www.sciencedirect.com[...]
Despite the vital importance of wetlands globally, these habitats have increasingly received anthropogenic materials, such as plastics, which can impact the wildlife these habitats support. Despite commonly found in the nests of Eurasian spoonbill (Platalea leucorodia), the presence of such materials has never been quantified. Here, we monitored the occurrence of anthropogenic nesting materials (ANM) in spoonbill nests in the Camargue wetland in Southern France during two breeding seasons (2021−2022). We also investigated their potential function by associating their presence with breeder experience (based on their age) and hatching success. Out of 439 nests, 39 % contained at least one anthropogenic material item, usually plastic of sheet-like shape and white-transparent colours. Throughout the breeding season, the proportion of ANM in the nest lining increased, coinciding with a decrease in natural materials (i.e. vegetation). A higher proportion of natural green materials was detected during the egg phase compared to other phases of nest development. Our results did not support a correlation between the proportion of ANM and breeder experience, nor with hatching success. Further studies (e.g., physiological through necropsy or fine temperature nest assessment) may disentangle the benefits and adverse effects of such materials on waterbird breeding success.
de Leslie-Anne Merleau, Aurélie Goutte, Anthony Olivier, Marion Vittecoq, Paco Bustamante, Carole Leray, Olivier Lourdais
In Science of The Total Environment, 954 (December, 2024), 177487
En ligne : linkinghub.elsevier.com[...]
Metallic trace elements (MTEs) constitute a major source of chemical pollution and represent a threat to aquatic ecosystems and organisms. Important variation in contamination may exist at a local scale in relation to the environment (hydrosystem, trophic ressources) and individual traits (age, sex). Heretofore, the factors influencing MTEs exposure of freshwater reptiles in temperate regions are not fully understood. Freshwater turtles have a relatively high trophic position and a long lifespan, thus being potentially highly exposed due to bioaccumulation and bioamplification processes. We investigated MTE blood concentrations from two populations of the European pond turtle (Emys orbicularis) in the Camargue wetland (France). These populations, monitored since 1997, differ in their habitat and exposure (irrigation versus drainage canal). In this study, we detected 7 MTEs (Cu, Fe, Hg, Mn, Pb, Se, and Zn) which levels depended on site and individual characteristics. Hg was positively related to body size and age, indicating an increase of exposure in older individuals. We found differences between males and females with the interaction with body size for Pb and Se and with age for Pb. Nitrogen and carbon stable isotopes varied only marginally between individuals and were poorly associated with MTEs concentrations, showing that trophic position might not explain MTEs contamination for these populations. At the individual level, Hg, Pb, and Se blood values were repeatable over years. Further studies should concentrate on potential ecophysiological effects to such exposure, especially since we recently evidenced that these populations of E. orbicularis are highly exposed to organic contaminants, which can lead to synergistic effects.
de Laura Patier, Paco Bustamante, Karen D. McCoy, Gaël Guillou, Abdessalem Hammouda, Carole Leray, Gonzalo Fernando Martínez Salcedo, Ana Payo-Payo, Gauthier Poiriez, Raul Ramos, et al.
In Environmental Pollution, 362 (December, 2024), 124992
En ligne : www.sciencedirect.com[...]
Mercury (Hg) is a global pollutant of major concern in marine and coastal environments. In the Mediterranean Sea, Hg concentrations in biota are higher than in other seas, even when seawater concentrations are similar. Seabirds, as marine top predators, can reflect Hg contamination on a large spatial scale. By sampling seabirds at 17 different breeding colonies, we evaluated Hg concentrations of yellow-legged gulls (Larus michahellis) in the occidental Mediterranean basin in 2021 and 2022. More specifically, we investigated spatial variation of Hg contamination in both chicks and adults as well as associated toxicological risks through the use of blood and feathers, which reflect contamination over different periods of the year. The highest concentrations in chicks were found in Djerba (Tunisia) with blood Hg values of (mean ± SD) 1.69 ± 0.51 μg g−1 dry weight (dw). Adults were most contaminated in Djerba and Dragonera (Balearic Islands, Spain) with blood Hg concentrations of respectively 3.78 ± 2.54 and 5.25 ± 3.73 μg g−1 dw. Trophic ecology was investigated using stable isotope analyses (δ13C, δ15N and δ34S as proxies of feeding habitat and diet), and showed that spatial variation in Hg was mainly driven by foraging habitat in both chicks and adults. Low Hg concentrations were related to the use of anthropogenic food sources. An effect of colony location was also found, suggesting spatial differences in local environmental pollution transfer up to seabirds. Our results also supported the use of δ34S to discriminate between marine and continental foraging habitats in generalist seabirds. This study provides new insights onto the spatial distribution of Hg contamination in a widespread seabird, reporting some of the highest Hg values recorded for this species. Populations with highest concentrations are of potential concern regarding toxicological risks.
de Florence Nono Almeida, Carole Leray, Charly Souc, Sara Scotto, Slaheddine Selmi, Abdessalem Hammouda, Raul Ramos, Alexandra ter Halle, Karen D. McCoy, Marion Vittecoq
In Marine pollution bulletin, 204 (July, 2024), 116508
En ligne : www.sciencedirect.com[...]
The Mediterranean region is both a hotspot for biodiversity and for the accumulation of plastic pollution. Many species are exposed to this pollution while feeding, including a wide diversity of seabirds. Our objective was to investigate spatial variation in the quantity and types of plastic ingested by Yellow-legged gulls using information obtained from regurgitated pellets collected in 11 colonies. Anthropogenic debris, and particularly plastic, was found in pellets from all colonies, but the amount varied considerably. This among-colony difference was stable over the two years of study. The presence of marine prey and the proportion of agricultural area around the colonies significantly influenced the number of ingested plastics. As landfills close and garbage management improves, the availability of anthropogenic waste should decline. Following the response of gulls to these changes will be particularly useful for monitoring plastic pollution and for understanding the response of opportunistic wildlife to environmental modifications.
de Charly Souc, Carole Leray, Thomas Blanchon, Thomas Dagonet, Marion Vittecoq, Raul Ramos, Karen D. McCoy
In Ibis, (en ligne) (June, 2024)
En ligne : onlinelibrary.wiley.com[...]
A recent study revealed that wing-harnessed tracking devices negatively affected reproductive success of Great Black-backed Gulls Larus marinus. To evaluate the generality of this effect in large gulls, we investigated the reproductive performance associated with the same type of GPS-mounted system in four Mediterranean breeding colonies of the Yellow-legged Gull Larus michahellis in 2022. We found no significant difference in reproductive parameters among adults handled with a mounted device, adults handled with no device, and controls, and no interaction with colony of origin. The impact of the GPS harness system on short-term reproduction is therefore not generalizable among larid species, and should be tested and reported whenever a new tracking programme is employed.
de Leslie-Anne Merleau, Olivier Lourdais, Anthony Olivier, Marion Vittecoq, Gabriel Blouin-Demers, Fabrice Alliot, Louisiane Burkart, Yvann Foucault, Carole Leray, Emmanuelle Migne, et al.
In Environmental Pollution, Online November (November, 2023), 11
En ligne : linkinghub.elsevier.com[...]
Wetlands are among the most threatened ecosystems on the planet and pollution is a major factor causing the decline of wetland biodiversity. Despite the increasing use of pesticides, their fate and effects on freshwater reptiles remain largely unknown. We studied the European pond turtle (Emys orbicularis), a long-lived species at risk with a high exposure potential to pesticides. Between 2018 and 2020, we measured 29 pesticides and metabolites in 408 blood samples of turtles from two populations in the Camargue wetland (France). We were able to quantify 24 compounds and at least one pesticide or one degradation product in 62.5% of samples. Pesticide occurrences and concentrations were low, except for a herbicide widely used in rice cultivation and locally detected in water: bentazone that reached high blood concentrations in E. orbicularis. The occurrence and the concentration of pesticides in E. orbicularis blood depended mainly on the site and the sampling date in relation to pesticide application. Individual characteristics (sex, age, body condition) did not explain the occurrence or the concentration of pesticides found in turtle blood. Assessing the exposure of aquatic wildlife to a cocktail of currently-used pesticides is a first and crucial step before studying their effects at the individual and population levels.Natal colony influences age-specific movement patterns of the Yellow-legged gull (Larus michahellis)
de Charly Souc, Nicolas Sadoul, Thomas Blanchon, Marion Vittecoq, Christophe Pin, Eric Vidal, Alain Mante, Remi Choquet, Karen D. McCoy
In Movement Ecology, 11(1) (August, 2023), 11
En ligne : doi.org[...]
As for other life history traits, variation occurs in movement patterns with important impacts on population demography and community interactions. Individuals can show variation in the extent of seasonal movement (or migration) or can change migratory routes among years. Internal factors, such as age or body condition, may strongly influence changes in movement patterns. Indeed, young individuals often tend to move across larger spatial scales compared to adults, but relatively few studies have investigated the proximate and ultimate factors driving such variation. This is particularly the case for seabirds in which the sub-adult period is long and difficult to follow. Here, we examine migration variation and the factors that affect it in a common Mediterranean seabird, the Yellow-legged gull (Larus michahellis).A soft tick vector of Babesia sp. YLG in Yellow-legged gull (Larus michahellis) nests
de Claire Bonsergent, Marion Vittecoq, Carole Leray, Maggy Jouglin, Marie Buysse, Karen D. McCoy, Laurence Malandrin
In Peer Community Journal, 3 (August, 2023)
En ligne : peercommunityjournal.org[...]
Babesia sp. YLG has recently been described in Yellow-legged gull (Larus michahellis) chicks and belongs to the Peircei clade in the new classification of Piroplasms. Here, we studied Babesia sp. YLG vectorial transmission by ticks in the simplified environment of a single seabird breeding colony where the Yellow-legged gull is the sole vertebrate host, Ornithodoros maritimus (syn. Alectorobius maritimus) the sole tick species, and Babesia sp. YLG is the only blood parasite species detected in chicks of the colony. We collected ticks over four years, maintained certain individuals through moulting or oviposition, and dissected fresh ticks to isolate different organs and test for the presence of the parasite using molecular assays. We report the first strong evidence of a Piroplasmidae transmitted by a soft tick. Indeed, Babesia sp. YLG DNA was detected in the salivary glands of nymphs, females and males, a necessary organ to infect for transmission to a new vertebrate host. Parasite DNA was also found in tick ovaries, which could indicate possible transovarial transmission. Our detection of Babesia sp. YLG DNA in several male testes and in endospermatophores, and notably in a parasite-free female (uninfected ovaries and salivary glands), raise the interesting possibility of sexual transmission from infected males to uninfected females. Future work in this system will now need to focus on the degree to which the parasite can be maintained locally by ticks and the epidemiological consequences of infection for both O. maritimus and its avian host.Antimicrobial-Resistant Bacteria Carriage in Rodents According to Habitat Anthropization
de Marion Vittecoq, Eric Elguero, Lionel Brazier, Nicolas Renaud, Thomas Blanchon, François Roux, François Renaud, Patrick Durand, Frederic Thomas
In EcoHealth, 20 (May, 2023)
En ligne : doi.org[...]
It is increasingly suggested that the dynamics of antimicrobial-resistant bacteria in the wild are mostly anthropogenically driven, but the spatial and temporal scales at which these phenomena occur in landscapes are only partially understood. Here, we explore this topic by studying antimicrobial resistance in the commensal bacteria from micromammals sampled at 12 sites from a large heterogenous landscape (the Carmargue area, Rhone Delta) along a gradient of anthropization: natural reserves, rural areas, towns, and sewage-water treatment plants. There was a positive relationship between the frequency of antimicrobial-resistant bacteria and the level of habitat anthropization. Although low, antimicrobial resistance was also present in natural reserves, even in the oldest one, founded in 1954. This study is one of the first to support the idea that rodents in human-altered habitats are important components of the environmental pool of resistance to clinically relevant antimicrobials and also that a “One Health” approach is required to assess issues related to antimicrobial resistance dynamics in anthropized landscapes.Changes in plastic ingestion by yellow-legged gulls (Larus michahellis) over the breeding season
de Florence Nono Almeida, Carole Leray, Justine Boutry, Alexandra ter Halle, Marion Vittecoq, Jennifer F. Provencher, Karen D. McCoy
In Marine pollution bulletin, 187 (February 2023), 9
En ligne : www.sciencedirect.com[...]
Gulls can be particularly vulnerable to ingesting plastics when using anthropogenic food sources, with potential consequences for survival and reproductive success. Although birds are known to switch foraging habitats over the breeding season to provide higher quality food for chick provisioning, it is unclear what this means regarding the ingestion of plastics. Here, we tested whether breeding gulls decrease the amount of plastic ingested during reproduction by collecting pellets from a series of monitored nests at a large yellow-legged gull (Larus michahellis) colony in southern France. We found at least one plastic item in 83.9 % of the analyzed pellets, with the most abundant plastic type being polyethylene-based sheet plastic. As predicted, we found a slight decrease in the number of plastic items in pellets at chick hatching. These results suggest that gulls, like other birds, may adjust foraging habits to provide more digestible, less risky, food to chicks.Les parasites au coeur de la biodiversité modelée par les activités humaines (2023)
de Marion Vittecoq
Montpellier : Université de Montpellier, 2023, 123
Marion Vittecoq a développé ses recherches depuis sa thèse, soutenue en 2012, jusqu’à aujourd’hui sous l’angle de la conservation des zones humides, écosystèmes associant grande biodiversité, forts liens avec les activités humaines et grande vulnérabilité. L'objectif, in fine, de ces recherches est de contribuer à concilier dans ces écosystèmes conservation et santé publique et vétérinaire. Les travaux de M. Vittecoq suivent depuis douze ans la même ligne, toutefois, elle l’aborde à travers de multiples modèles d’hôtes et de parasites. Toutes les questions auxquelles elle s’intéresse sont liées à la dynamique des communautés hôtes-parasites au sein des zones humides dans le temps, l’espace et à l’épreuve des activités humaines. Actuellement elle développe, avec ses partenaires, deux grands projets associant suivis à long-terme individuels d’histoire de vie d’animaux longévifs et caractérisation de leur exposition à différents polluants et pathogènes afin de comprendre les impacts combinés de ces différentes pressions. Un premier projet, mené à l’échelle nationale est centré sur la cistude d’Europe et les milieux d’eau douce, le second se déploie à l’échelle de l’Ouest du bassin Méditerranéen et est centré sur le goéland leucophée et les milieux littoraux. M Vittecoq travaille par ailleurs sur le rôle de la faune sauvage dans la dynamique des antibiorésistances en étudiant ces bactéries chez les rongeurs, les oiseaux et dans l’eau, principalement en Camargue. Elle s'’intéresse également à la diversité des trématodes dans le delta du Rhône et aux facteurs associés à leur transmission chez la faune sauvage et les bovins. L’originalité de l’approche choisie dans ces différents travaux est de coupler l’étude de différentes pressions (pollution, multiples pathogènes, gestion du milieu par les humains) avec les suivis à long-terme des espèces hôtes et de leur milieu.Multiresistant Enterobacteriaceae in yellow-legged gull chicks in their first weeks of life
de Marion Vittecoq, Lionel Brazier, Eric Elguero, Ignacio G. Bravo, Nicolas Renaud, Alejandro Manzano-Marín, Franck Prugnolle, Sylvain Godreuil, Thomas Blanchon, François Roux, et al.
In Ecology and Evolution, 12(6) (June, 2022), 10
En ligne : onlinelibrary.wiley.com[...]
Wild animal species living in anthropogenic areas are commonly carriers of antimicrobial-resistant bacteria (AMRB), but their role in the epidemiology of these bacteria is unclear. Several studies on AMRB in wildlife have been cross-sectional in design and sampled individual animals at only one point in time. To further understand the role of wildlife in maintaining and potentially transmitting these bacteria to humans and livestock, longitudinal studies are needed in which samples are collected from individual animals over multiple time periods. In Europe, free-ranging yellow-legged gulls (Larus michahellis) commonly live in industrialized areas, forage in landfills, and have been found to carry AMRB in their feces. Using bacterial metagenomics and antimicrobial resistance characterization, we investigated the spatial and temporal patterns of AMRB in a nesting colony of yellow-legged gulls from an industrialized area in southern France. We collected 54 cloacal swabs from 31 yellow-legged gull chicks in 20 nests on three dates in 2016. We found that AMRB in chicks increased over time and was not spatially structured within the gull colony. This study highlights the complex occurrence of AMRB in a free-ranging wildlife species and contributes to our understanding of the public health risks and implications associated with ARMB-carrying gulls living in anthropogenic areas.
de Marion Vittecoq
In Environnement, Risques & Santé, 21(3) (May, 2022), 201-204
En ligne : www.jle.com[...]
Putting the “One health” approach into action, not just how but why The reason to put the “One health” approach into practice may seem obvious. However, the different sectors and disciplines involved in this approach may not see it in the same light. In this article, we try to understand the underlying difficulty in answering a seemingly simple question. In particular, we highlight the different definitions of health as applied to humans, animals and ecosystems. We also note that, while plant health is included in the One health approach, it does not appear as clearly as animal health, which raises questions about the status of cultivated plants within this concept. We thus suggest showing how the different health sectors overlap rather than merely juxtaposing them. As there is no simple solution to converge the definitions and objectives of the different sectors involved, we also stress the need for a continuous and dynamic dialogue between the various actors. Finally, since working with the living world is an inherently ongoing process, we suggest that the objectives and implementation of initiatives to advance the “One health” approach should also be dynamic.Les aires protégées françaises face aux approches conceptuelles « Une seule santé – Ecohealth »:
de Thierry Durand, Olivier Fleury, Marie Heuret, Thierry Mougey, Christian Schwoehrer, Marion Vittecoq
In Environnement, Risques & Santé, 21(3) (May, 2022), 227-234
En ligne : www.jle.com[...]
One health and Ecohealth in protected areas in France Protected areas (PAs) are intended to preserve the health of humans, animals and ecosystems and to meet the global challenges of biodiversity and climate change. The key role of French PAs as preferential sites for turning the “One health” concept into practice is highlighted.
de Gema L. Batanero, Andy J. Green, Juan A. Amat, Marion Vittecoq, Curtis A. Suttle, Isabel Reche
In Aquatic Sciences, 84(2) (March, 2022), 22
En ligne : doi.org[...]
Coastal wetlands are valuable aquatic ecosystems with high biological productivity, which provide services such as a reduction in nitrogen loading into coastal waters and storage of organic carbon acting as carbon dioxide sinks. The predicted rise of sea level or freshwater extractions, particularly in the arid Mediterranean biome, will salinize many coastal wetlands. However, there is considerable uncertainty about how salinization will affect microbial communities and biogeochemical processes. We determined the abundance of total prokaryotes, cyanobacteria, and viruses and quantified the heterotrophic production of prokaryotes sensitive- (predominantly Bacteria) and resistant- (predominantly Archaea) to erythromycin in 112 ponds from nine coastal wetlands. We explored the main drivers of prokaryotic abundance and heterotrophic production using generalized linear models (GLMs). The best GLM, including all the wetlands, indicated that the concentration of total dissolved nitrogen (TDN) positively affected the total abundance of prokaryotes and the heterotrophic erythromycin-resistant (ery-R) production. In contrast, heterotrophic erythromycin-sensitive (ery-S) production was negatively related to TDN. This negative relationship appeared to be mediated by salinity and virus abundance. Heterotrophic ery-S production declined as salinity and virus abundance increased. Consequently, we observed a switch from heterotrophic ery-S production towards ery-R production as salinity and virus abundance increased. Our results imply that microbial activity will change from heterotrophic bacterial-dominated processes to archaeal-dominated processes with anthropogenic nitrogen and salinization increases. However, more studies are required to link the mineralization rates of dissolved nitrogen and organic carbon with specific archaeal taxa to enable more accurate predictions on future scenarios in coastal wetlands.On the arrival of fasciolosis in the Americas
de Antonio A. Vázquez, Annia Alba, Pilar Alda, Marion Vittecoq, Sylvie Hurtrez-Boussès
In Trends in Parasitology, 38(3) (March, 2022), 195-204
En ligne : www.sciencedirect.com[...]
Fasciola hepatica is a worldwide emerging and re-emerging parasite heavily affecting several regions in South America. Some lymnaeid snail species of American origin are among the major hosts of F. hepatica worldwide. Recent paleoparasitological findings detected its DNA in a 2300-year-old sample in Patagonia, countering the common hypothesis of the recent arrival of F. hepatica in the Americas during European colonization. Thus, the theory of an initial introduction in the 1500s can no longer be sustained. This article discusses how it was possible for F. hepatica to reach and spread in the Americas in relation to the availability and compatibility of hosts through natural and incidental introductions. Our study will serve to better understand the ongoing Neotropical scenario of fasciolosis.
de Marion Vittecoq
In H & B, 7 (2021), 50-55On the need for integrating cancer into the One Health perspective
de Antoine Dujon, Joel S. Brown, Delphine Destoumieux‐Garzón, Marion Vittecoq, Rodrigo Hamede, Aurelie Tasiemski, Justine Boutry, Sophie Tissot, Catherine Alix‐Panabieres, Pascal Pujol, et al.
In Evolutionary Applications, 14(11) (November, 2021), 2571-2575
En ligne : onlinelibrary.wiley.com[...]
Recent pandemics have highlighted the urgency to connect disciplines studying animal, human, and environment health, that is, the “One Health” concept. The One Health approach takes a holistic view of health, but it has largely focused on zoonotic diseases while not addressing oncogenic processes. We argue that cancers should be an additional key focus in the One Health approach based on three factors that add to the well-documented impact of humans on the natural environment and its implications on cancer emergence. First, human activities are oncogenic to other animals, exacerbating the dynamics of oncogenesis, causing immunosuppressive disorders in wildlife with effects on host–pathogen interactions, and eventually facilitating pathogen spillovers. Second, the emergence of transmissible cancers in animal species (including humans) has the potential to accelerate biodiversity loss across ecosystems and to become pandemic. It is crucial to understand why, how, and when transmissible cancers emerge and spread. Third, translating knowledge of tumor suppressor mechanisms found across the Animal Kingdom to human health offers novel insights into cancer prevention and treatment strategies.
de Claire Bonsergent, Marion Vittecoq, Carole Leray, Louisiane Burkart, Karen D. McCoy, Laurence Malandrin
In Ticks and Tick-borne Diseases, Online (October, 2021), 101852
En ligne : www.sciencedirect.com[...]
Avian infecting piroplasms are largely under-studied compared to other hemoparasites, and this paucity of information has blurred our phylogenetic and biological comprehension of this important group as a whole. In the present study, we detected and characterized Babesia from yellow-legged gull (Larus michahellis) chicks from a colony in southern France. Based on morphological and molecular characterizations, a new Babesia species belonging to the Peircei group, a clade of avian-specific piroplasms, was identified. Due to the complexity of species delineations and the low number of parasites characterized in this clade to date, a species name was not yet attributed; we refer to it for now as Babesia sp. YLG (Yellow-Legged Gull). High prevalence (85% and 58% in 2019 and 2020, respectively) and high parasitemia (up to 20% of parasitized erythrocytes) were recorded in chicks, without any obvious clinical signs of infection. Although the 16 isolates had identical 18S rRNA gene sequences, 6 genetic variants were described based on partial cox1 sequencing, with evidence of chicks co-infected by two variants. Transmission of Babesia sp. YLG via the soft tick Ornithodoros maritimus is discussed.Machine learning is a powerful tool to study the effect of cancer on species and ecosystems
de Antoine M. Dujon, Marion Vittecoq, Georgina Bramwell, Frederic Thomas, Beata Ujvari
In Methods in Ecology and Evolution, Online (August, 2021), 2041-210X.13703
En ligne : onlinelibrary.wiley.com[...]
Cancer is an understudied but important process in wildlife. Cancerous cells are proposed to have had significant effect on the evolution of metazoan species due to their negative effect on host fitness. However, gaining knowledge on the impact of cancer on species and ecosystems is currently relatively slow as it requires expertise in both ecology and oncology. The field can greatly benefit from automation to reduce the need of excessive manpower and analyse complex ecological datasets.
In this commentary, we examine how machine learning has been used to gain knowledge on oncogenic processes in wildlife. Using a landscape ecology approach, we explore spatial scales ranging from the size of a molecule up to whole ecosystems and detail, for each level, how machine learning has been used, or could contribute to obtain insights on cancer in wildlife populations and ecosystems.
We illustrate how machine learning is a powerful toolbox to conduct studies at the interface of ecology and oncology. We provide guidance for the readers of both fields on how to implement machine learning tools in their research and identify directions to move the field forward using this promising technology. We demonstrate how applying machine learning to complex ecological datasets will (a) contribute to quantitating the effect of cancer at different life stages in wildlife; (b) allow the mining of long-term datasets to understand the spatiotemporal variability of cancer risk factors and (c) contribute to mitigating cancer risk factors and the conservation of endangered species.
With this study, we aim to facilitate the use of machine learning to wildlife species and to encourage discussion between the scientists of the fields of oncology and ecology. We highlight the importance of international and pluridisciplinary collaborations to collect high-quality datasets on which efficient machine learning algorithms can be trained.
de F. Vorimore, M. Hölzer, E. M. Liebler-Tenorio, L. -M. Barf, S. Delannoy, Marion Vittecoq, R. Wedlarski, A. Lécu, S. Scharf, Y. Blanchard, et al.
In Systematic and Applied Microbiology, 44(4) (July, 2021), 15
En ligne : www.sciencedirect.com[...]
The family Chlamydiaceae currently comprises a single genus Chlamydia, with 11 validly published species and seven more taxa. It includes the human pathogens Chlamydia (C.) trachomatis, C. pneumoniae and C. psittaci, a zoonotic agent causing avian chlamydiosis and human psittacosis, as well as other proven or potential pathogens in ruminants, birds, snakes, reptiles and turtles. During routine testing of 15 apparently healthy captive flamingos in a zoo in 2011, an atypical strain of Chlamydiaceae was detected by real-time PCR of cloacal swab samples. Sequence analysis of the 16S rRNA gene revealed high similarity to the uncultured Chlamydiales bacterium clone 122, which previously had been found in gulls. As more samples were collected during annual campaigns of the flamingo ringing program in southern France from 2012 to 2015, Chlamydiaceae-specific DNA was detected by PCR in 30.9% of wild birds. From these samples, three strains were successfully grown in cell culture. Ultrastructural analysis, comparison of 16S and 23S rRNA gene sequences, whole-genome analysis based on de novo hybrid-assembled sequences of the new strains as well as subsequent calculation of taxonomic parameters revealed that the relatedness of the flamingo isolates to established members of the family Chlamydiaceae was sufficiently distant to indicate that the three strains belong to two distinct species within a new genus. Based on these data, we propose the introduction of Chlamydiifrater gen. nov., as a new genus, and Chlamydiifrater phoenicopteri sp. nov. and Chlamydiifrater volucris sp. nov., as two new species of the genus.
de Louisiane Burkart, Anthony Olivier, Olivier Lourdais, Marion Vittecoq, Gabriel Blouin‐Demers, Fabrice Alliot, Clément Le Gac, Nicolas Martin, Aurélie Goutte
In Environmental Toxicology and Chemistry, 40(8) (May, 2021)
En ligne : setac.onlinelibrary.wiley.com[...]
Many banned persistent organic pollutants (POPs) remain for decades in the aquatic environment and can have harmful effects on long-lived predators because of their high bioaccumulation and biomagnification potentials. We investigated the occurrence and levels of 18 polychlorinated biphenyls (PCBs) and 16 organochlorine pesticides (OCPs) in European pond turtles (n = 174) from April to July 2018 in the Camargue wetland, France. Although the Camargue was highly contaminated in previous decades, plasma occurrence and levels of POPs were very low: we were able to quantify only three of the 34 compounds we analyzed in more than 10% of the turtles. POP burdens did not differ between males and females and were uncorrelated with sampling date and body mass. We observed differences in POP burdens between turtles from the two sampling sites. One possible explanation is that the sampling sites were in different agricultural hydraulic system: plasma occurrence and levels were higher for PCB-52 and HCB in turtles captured in drainage channels, and for PCB-153 at the site that receives irrigation. Finally, the occurrence and levels of PCB 153 in turtles increased with age, likely because of bioaccumulation and much higher exposure 20-30 years ago than now. This article is protected by copyright. All rights reserved.Reliability of animal counts and implications for the interpretation of trends
de David Vallecillo, Michel Gauthier-Clerc, Matthieu Guillemain, Marion Vittecoq, Philippe Vandewalle, Benjamin Roche, Jocelyn Champagnon
In Ecology and Evolution, 11(5) (January, 2021)
En ligne : onlinelibrary.wiley.com[...]
Population time series analysis is an integral part of conservation biology in the current context of global changes. To quantify changes in population size, wildlife counts only provide estimates because of various sources of error. When unaccounted for, such errors can obscure important ecological patterns and reduce confidence in the derived trend. In the case of highly gregarious species, which are common in the animal kingdom, the estimation of group size is an important potential bias, which is characterized by high variance among observers. In this context, it is crucial to quantify the impact of observer changes, inherent to population monitoring, on i) the minimum length of population time series required to detect significant trends and ii) the accuracy (bias and precision) of the trend estimate. We acquired group size estimation error data by an experimental protocol where 24 experienced observers conducted counting simulation tests on group sizes. We used this empirical data to simulate observations over 25 years of a declining population distributed over 100 sites. Five scenarios of changes in observer identity over time and sites were tested for each of three simulated trends (true population size evolving according to deterministic models parameterized with declines of 1.1%, 3.9% or 7.4% per year that justify respectively a “declining,” “vulnerable” or “endangered” population under IUCN criteria). We found that under realistic field conditions observers detected the accurate value of the population trend in only 1.3% of the cases. Our results also show that trend estimates are similar if many observers are spatially distributed among the different sites, or if one single observer counts all sites. However, successive changes in observer identity over time lead to a clear decrease in the ability to reliably estimate a given population trend, and an increase in the number of years of monitoring required to adequately detect the trend. Minimizing temporal changes of observers improve the quality of count data and help taking appropriate management decisions and setting conservation priorities. The same occurs when increasing the number of observers spread over 100 sites. If the population surveyed is composed of few sites, then it is preferable to perform the survey by one observer. In this context, it is important to reconsider how we use estimated population trend values and potentially to scale our decisions according to the direction and duration of estimated trends, instead of setting too precise threshold values before action.
de Antonio A. Vázquez, Emeline Sabourin, Pilar Alda, Clémentine Leroy, Carole Leray, Eric Carron, Stephen Mulero, Céline Caty, Sarah Hasfia, Michel Boisseau, et al.
In Transboundary and Emerging Diseases, 68(4) (November, 2020)
En ligne : onlinelibrary.wiley.com[...]
Fasciolosis is a worldwide spread parasitosis mainly caused by the trematode Fasciola hepatica. This disease is particularly important for public health in tropical regions, but it can also affect the economies of many developed countries due to large infections in domestic animals. Although several studies have tried to understand the transmission by studying the prevalence of different host species, only a few have used population genetic approaches to understand the links between domestic and wildlife infections. Here, we present the results of such genetic approach combined with classical parasitological data (prevalence and intensity) by studying domestic and wild definitive hosts from Camargue (southern France) where fasciolosis is considered as a problem. We found 60% of domestic hosts (cattle) infected with F. hepatica but lower values in wild hosts (nutria, 19%; wild boars, 4.5%). We explored nine variable microsatellite loci for 1,148 adult flukes recovered from four different populations (non-treated cattle, treated cattle, nutria and wild boars). Populations from the four groups differed, though we found a number of migrants particularly non-treated cattle and nutria. Overall, we detected 729 different multilocus genotypes (from 783 completely genotyped individuals) and only 46 genotypes repeated across samples. Finally, we experimentally infected native and introduced intermediate snail hosts to explore their compatibility with F. hepatica and assess the risks of fasciolosis expansion in the region. The introduced species Galba truncatula and Pseudosuccinea columella attained the higher values of overall compatibility in relation to the European species. However, concerning the origin, sympatric combinations of G. truncatula were more compatible (higher prevalence, intensity and survival) than the allopatric tested. According to our results, we should note that the assessment of epidemiological risks cannot be limited to a single host–parasite system, but should focus on understanding the diversity of hosts in the heterogeneous environment through space and time.Evaluating Functional Dispersal in a Nest Ectoparasite and Its Eco-Epidemiological Implications
de Amalia Rataud, Marlene Dupraz, Céline Toty, Thomas Blanchon, Marion Vittecoq, Remi Choquet, Karen D. McCoy
In Frontiers in Veterinary Science, 7 (October, 2020), 722
En ligne : www.frontiersin.org[...]
Functional dispersal (between-site movement, with or without subsequent reproduction) is a key trait acting on the ecological and evolutionary trajectories of a species, with potential cascading effects on other members of the local community. It is often difficult to quantify, and particularly so for small organisms such as parasites. Understanding this life history trait can help us identify the drivers of population dynamics and, in the case of vectors, the circulation of associated infectious agents. In the present study, functional dispersal of the soft tick Ornithodoros maritimus was studied at a small scale, within a colony of yellow-legged gulls (Larus michahellis). Previous work showed a random distribution of infectious agents in this tick at the within-colony scale, suggesting frequent tick movement among nests. This observation contrasts with the presumed strong endophilic nature described for this tick group. By combining an experimental field study, where both nest success and tick origin were manipulated, with Capture-Mark-Recapture modeling, dispersal rates between nests were estimated taking into account tick capture probability and survival, and considering an effect of tick sex. As expected, tick survival probability was higher in successful nests, where hosts were readily available for the blood meal, than in unsuccessful nests, but capture probability was lower. Dispersal was low overall, regardless of nest state or tick sex, and there was no evidence for tick homing behavior; ticks from foreign nests did not disperse more than ticks in their nest of origin. These results confirm the strong endophilic nature of this tick species, highlighting the importance of life cycle plasticity for adjusting to changes in host availability. However, results also raise questions with respect to the previously described within-colony distribution of infectious agents in ticks, suggesting that tick dispersal either occurs over longer temporal scales and/or that transient host movements outside the breeding period result in vector exposure to a diverse range of infectious agents.
de Yann Gomard, Olivier Flores, Marion Vittecoq, Thomas Blanchon, Céline Toty, Olivier Duron, Patrick Mavingui, Pablo Tortosa, Karen D. McCoy
In Microbial Ecology, Online (October, 2020)
En ligne : doi.org[...]
Characterising within-host microbial interactions is essential to understand the drivers that shape these interactions and their consequences for host ecology and evolution. Here, we examined the bacterial microbiota hosted by the seabird soft tick Ornithodoros maritimus (Argasidae) in order to uncover bacterial interactions within ticks and how these interactions change over tick development. Bacterial communities were characterised through next-generation sequencing of the V3–V4 hypervariable region of the bacterial 16S ribosomal RNA gene. Bacterial co-occurrence and co-exclusion were determined by analysing networks generated from the metagenomic data obtained at each life stage. Overall, the microbiota of O. maritimus was dominated by four bacterial genera, namely Coxiella, Rickettsia, Brevibacterium and Arsenophonus, representing almost 60% of the reads. Bacterial diversity increased over tick development, and adult male ticks showed higher diversity than did adult female ticks. Bacterial networks showed that co-occurrence was more frequent than co-exclusion and highlighted substantial shifts across tick life stages; interaction networks changed from one stage to the next with a steady increase in the number of interactions through development. Although many bacterial interactions appeared unstable across life stages, some were maintained throughout development and were found in both sexes, such as Coxiella and Arsenophonus. Our data support the existence of a few stable interactions in O. maritimus ticks, on top of which bacterial taxa accumulate from hosts and/or the environment during development. We propose that stable associations delineate core microbial interactions, which are likely to be responsible for key biological functions.
de Anaïs Goulas, Drifa Belhadi, Alexandre Descamps, Antoine Andremont, Pierre Benoit, Sophie Courtois, Christophe Dagot, Nathalie Grall, David Makowski, Sylvie Nazaret, et al.
In Environmental Evidence, 9(1) (February, 2020), 4
En ligne : doi.org[...]
Antibiotic resistance is a major concern for public and environmental health. The role played by the environment in disseminating resistance is increasingly considered, as well as its capacity for mitigation. We reviewed the literature on strategies to control dissemination of antibiotic-resistant bacteria (ARB), antibiotic resistance genes (ARG) and mobile genetic elements (MGE) in the environment.
de Antonio A. Vázquez, Mercedes de Vargas, Annia Alba, Jorge Sánchez, Pilar Alda, Emeline Sabourin, Marion Vittecoq, Pedro M. Alarcón-Elbal, Jean-Pierre Pointier, Sylvie Hurtrez-Boussès
In Veterinary Parasitology, 275 (November, 2019), 108955
En ligne : www.sciencedirect.com[...]
Fasciolosis is an important food-borne parasitic disease affecting over two million people worldwide with economic losses related to cattle production of up to US$ 3 billion annually. Despite the long known presence of Fasciola hepatica in the Caribbean islands its transmission is not well known. This study reviews historical and recent data on fasciolosis in the West Indies, revealing for the first time the outcomes of sympatric and allopatric fluke/snail interactions in the area by exploring the susceptibility of four lymnaeid species after exposure to F. hepatica isolates from Cuba, the Dominican Republic and France. Overall, Galba cubensis showed a mean prevalence of 71.8% and appears to be the most suitable intermediate host species irrespective of the isolate used. Sympatric combinations (snail and parasite from the same country) were generally more compatible (higher susceptibility, parasite intensity and snail survival post-exposure) and only the allopatric interaction of French G. truncatula/Cuban F. hepatica attained 100% prevalence and mean intensity over 33 rediae/snail. However, certain Dominican populations of Pseudosuccinea columella showed high parasite intensities (>30 rediae/snail) when infected with Cuban flukes, highlighting the potential risks of biological introductions. Overall, high compatibility in most sympatric combinations compared to low or moderate compatibility in allopatric ones, suggests the existence of local adaptation from a long sustained interaction that has led to high rates of transmission. Interestingly, attempts to infect G. schirazensis with sympatric and allopatric flukes failed and coupled with the lowest survival rates which supposes a low risk of fasciolosis transmission in areas where this is the only snail species. Although there are significant gaps in the actual status of fasciolosis transmission from several islands in the West Indies these results show a permanent risk. We conclude that fasciolosis transmission is high in areas where the local snail, G. cubensis, occurs, and will be even higher in the presence of the invasive P. columella.Evaluating functional dispersal and its eco-epidemiological implications in a nest ectoparasite
de Amalia Rataud, Marlene Dupraz, Céline Toty, Thomas Blanchon, Marion Vittecoq, Remi Choquet, Karen D. McCoy
In Zenodon, reviewed and recommended by Peer Community In Ecology, 10.5281/zenodo.2573075 (March, 2019), 18
En ligne : zenodo.org[...]
Functional dispersal (between-site movement, with or without subsequent reproduction) is a key trait acting on the ecological and evolutionary trajectories of a species, with potential cascading effects on other members of the local community. It is often difficult to quantify, and particularly so for small organisms such as parasites. Understanding this life history trait can help us identify the drivers of population dynamics and, in the case of vectors, the circulation of associated infectious agents. In the present study, functional dispersal of the soft tick Ornithodoros maritimus was studied at small scale, within a colony of yellow-legged-gulls (Larus michahellis). Previous work showed a random distribution of infectious agents in this tick at the within-colony scale, suggesting frequent tick movement among nests. This observation contrasts with the presumed strong endophilic nature described for this tick group. By combining an experimental field study, where both nest success and tick origin were manipulated, with Capture-Mark-Recapture modeling, dispersal rates between nests were estimated taking into account both tick capture probability and survival, and considering an effect of tick sex. As expected, tick survival probability was higher in successful nests, where hosts were readily available for the blood meal, than in unsuccessful nests, but capture probability was lower. Dispersal was low overall, regardless of nest state or tick sex, and there was no evidence for tick homing behavior; ticks from foreign nests did not disperse more than ticks in their nest of origin. These results confirm the strong endophilic nature of this tick species, highlighting the importance of life cycle plasticity for adjusting to changes in host availability. However, results also raise questions with respect to the previously described within-colony distribution of infectious agents in ticks, suggesting that tick dispersal either occurs over longer temporal scales and/or that transient host movements outside the breeding period result in vector exposure to a diverse range of infectious agents.Détectives à plumes. Ce que les oiseaux nous apprennent sur leur environnement
de David Grémillet, Marion Vittecoq, Thierry Boulinier
In Les dossiers d'Agropolis International, 24 (Février 2019), p. 37
En ligne : www.agropolis.fr[...]
Visibles de tous, les oiseaux nous renseignent sur l’état de leurs milieux de vie. Ils y sont exposés aux pollutions plastiques et chimiques, aux agents pathogènes, aux conséquences des changements climatiques et à la surexploitation des ressources naturelles. Bioindicateurs avérés, les oiseaux marins présentent des réponses qualitatives et/ou quantitatives aux changements globaux et émergent comme d’excellentes sentinelles environnementales
de Annia Alba, Antonio A. Vázquez, Jorge Sánchez, David Duval, Hilda M. Hernández, Emeline Sabourin, Marion Vittecoq, Sylvie Hurtrez-Boussès, Benjamin Gourbal
In Parasites & Vectors, 11(1) (October 2018)
En ligne : parasitesandvectors.biomedcentral.com[...]
Pseudosuccinea columella is one of the most widespread vectors of Fasciola hepatica, a globally distributed trematode that affects humans, livestock and wildlife. The exclusive occurrence in Cuba of susceptible and naturally-resistant populations to F. hepatica within this snail species, offers a fascinating model for evolutionary biology, health sciences and vector control strategies. In particular, resistance in P. columella is characterized by the encapsulation of the parasite by host’s immune cells and has been experimentally tested using different Cuban F. hepatica isolates with no records of successful infection. Here, we aimed to explore for the first time, the effect of different parasite doses, successive exposures and different parasite origins on the infection outcomes of the two phenotypes of P. columella occurring in Cuba.Impact of Human Activities on Fasciolosis Transmission
de Emeline Sabourin, Pilar Alda, Antonio Vázquez, Sylvie Hurtrez-Boussès, Marion Vittecoq
In Trends in Parasitology, 34(10) (October 2018), 891-903
En ligne : linkinghub.elsevier.com[...]
Fasciolosis is a neglected water- and food-borne disease. There are approximately 17 million human cases annually in the world. In some areas, these numbers may be underestimated.
This disease has an important worldwide distribution due to parasite proliferation in a wide range of freshwater snail species and domestic as well as wild mammals, including humans.
Fasciolosis is also considered to be a major veterinary problem because it is responsible for significant losses of productive capacity in livestock (meat and milk).
The (re)emergence of fasciolosis in certain countries can be explained by the recent evolution of human activities, such as the building of irrigation systems, livestock management, the use of unsafe water, and raw vegetable consumption.
Fasciolosis is a worldwide disease caused by the liver fluke Fasciola spp. This food- and water-borne disease is a major public health and veterinary issue. It is currently (re)emerging in several regions mainly due to the rapid evolution of human activities. This article reviews the current knowledge of the impact of irrigation-system management, livestock management, and human diet and hygiene habits on the emergence of fasciolosis. We also identify the gaps in this knowledge and the possible solutions for limiting these impacts. Integrated control seems to be the most effective solution for controlling fasciolosis, because it enables monitoring, prevention, and rapid action in case of the (re)emergence of the disease.
Antibioresistances, un défi environnemental
de Marion Vittecoq
In Espaces naturels, 63 (Juillet 2018), 31Genetic diversity, inbreeding and cancer
de Beata Ujvari, Marcel Klaassen, Nynke Raven, Tracey Russell, Marion Vittecoq, Rodrigo Hamede, Frederic Thomas, Thomas Madsen
In Proceedings of the Royal Society of London B: Biological Sciences, 285(1875) (March 2018), 1-8
En ligne : rspb.royalsocietypublishing.org[...]
Genetic diversity is essential for adaptive capacities, providing organisms with the potential of successfully responding to intrinsic and extrinsic challenges. Although a clear reciprocal link between genetic diversity and resistance to parasites and pathogens has been established across taxa, the impact of loss of genetic diversity by inbreeding on the emergence and progression of non-communicable diseases, such as cancer, has been overlooked. Here we provide an overview of such associations and show that low genetic diversity and inbreeding associate with an increased risk of cancer in both humans and animals. Cancer being a multifaceted disease, loss of genetic diversity can directly (via accumulation of oncogenic homozygous mutations) and indirectly (via increased susceptibility to oncogenic pathogens) impact abnormal cell emergence and escape of immune surveillance. The observed link between reduced genetic diversity and cancer in wildlife may further imperil the long-term survival of numerous endangered species, highlighting the need to consider the impact of cancer in conservation biology. Finally, the somewhat incongruent data originating from human studies suggest that the association between genetic diversity and cancer development is multifactorial and may be tumour specific. Further studies are therefore crucial in order to elucidate the underpinnings of the interactions between genetic diversity, inbreeding and cancer.Turning natural adaptations to oncogenic factors into an ally in the war against cancer
de Marion Vittecoq, Mathieu Giraudeau, Tuul Sepp, David J. Marcogliese, Marcel Klaassen, François Renaud, Beata Ujvari, Frederic Thomas
In Evolutionary Applications, https://doi.org/10.1111/eva.12608 (March 2018)
En ligne : doi.wiley.com[...]
Both field and experimental evolution studies have demonstrated that organisms naturally or artificially exposed to environmental oncogenic factors can, sometimes rapidly, evolve specific adaptations to cope with pollutants and their adverse effects on fitness. Although numerous pollutants are mutagenic and carcinogenic, little attention has been given to exploring the extent to which adaptations displayed by organisms living in oncogenic environments could inspire novel cancer treatments, through mimicking the processes allowing these organisms to prevent or limit malignant progression. Building on a substantial knowledge base from the literature, we here present and discuss this progressive and promising research direction, advocating closer collaboration between the fields of medicine, ecology, and evolution in the war against cancer.Cancer Is Not (Only) a Senescence Problem
de Frederic Thomas, Fabrice Vavre, Tazzio Tissot, Marion Vittecoq, Mathieu Giraudeau, Florence Bernex, Dorothee Misse, François Renaud, Nynke Raven, Christa Beckmann, et al.
In Trends in Cancer, 4(3) (2018-03-01), 169-172
En ligne : www.cell.com[...]
Age is one of the strongest predictors of cancer and risk of death from cancer. Cancer is therefore generally viewed as a senescence-related malady. However, cancer also exists at subclinical levels in humans and other animals, but its earlier effects on the body are poorly known by comparison. We argue here that cancer is a significant but ignored burden on the body and is likely to be a strong selective force from early during the lifetime of an organism. It is time to adopt this novel view of malignant pathologies to improve our understanding of the ways in which oncogenic phenomena influence the ecology and evolution of animals long before their negative impacts become evident and fatal.
de Marion Vittecoq, Hermann Gauduin, Thibault Oudart, Olivier Bertrand, Benjamin Roche, Matthieu Guillemain, Olivier Boutron
In Science of The Total Environment, 595 (octobre 1, 2017), 787-800
En ligne : www.sciencedirect.com[...]
Wild aquatic birds represent a natural reservoir of avian influenza viruses (AIV) that can be spread to poultry. AIV epizootics were associated with huge economic impacts during the last decades and are still of major concern. Within aquatic bird populations AIV are transmitted either by direct contact or through the ingestion of water that has been contaminated by infected individuals. This second route involving environmental transmission is of utmost importance in AIV dynamics, yet it has received far less attention than direct bird-to-bird contamination. Our objective was to combine a hydrodynamic model with data on mallard abundance and AIV infection rate within the population, so as to characterize virus dissemination within a complex wetland network. We chose the Vaccarès hydrosystem as a wetland model since it represents a large part of the Camargue region, which is a major wintering site for a large diversity of aquatic birds including AIV hosts. We aimed to identify the environmental parameters that drive AIV dynamics within this system and the spatio-temporal pattern of dispersion and persistence of viruses. Our results show that in a complex hydrosystem we can expect a great heterogeneity in AIV risk among wetlands. Our simulations underline how a simple “homogeneous box” approach could in the case of deltaic ecosystems minimize the expected risk by diluting it in the whole system. Moreover, such undermining of the risk perception could affect the predictions relative to risk duration. We present a new approach to identify hotspots of virus concentrations within deltaic areas that could take advantage of the duck count data, AIV surveys and hydrodynamic models that may already be available in several major duck wintering areas comprised of complex hydrosystems, such as the large European deltas. Our method could be of particular interest to optimize surveillance strategies in the current context of highly pathogenic AIV diffusion within wild bird populations. / Les auteurs ont modélisé le devenir des virus des grippes aviaires dans l’hydrosystème Vaccarès selon différents scénarios.Ils ont couplé les données hydrologiques du système avec celles dont nous disposons sur la présence des canards hôtes des virus Influenza A, agents des grippes aviaires, sur leur taux d’infection par ces virus et sur la persistance dans l’eau de ces derniers. Ils ont ensuite étudié comment se répartissaient les virus dans les différentes parties de l’hydrosystème Vaccarès en fonction de leur lieu et de leur date d’arrivée.
Il s’agit d’une première étape dans le développement d’un outil de modélisation des dynamiques des VIA dans l’eau en Camargue qui pourra à terme contribuer à optimiser la surveillance et à guider les prises de décision en cas de crise.
de Marlene Dupraz, Céline Toty, Elodie Devillers, Thomas Blanchon, Eric Elguero, Marion Vittecoq, Sara Moutailler, Karen D. McCoy
In International Journal for Parasitology: Parasites and Wildlife, 6(2) (08/2017), 122-130
En ligne : www.sciencedirect.com[...]
The epidemiology of vector-borne zoonoses depends on the movement of both hosts and vectors, which can differ greatly in intensity across spatial scales. Because of their life history traits and small size, vector dispersal may be frequent, but limited in distance. However, little information is available on vector movement patterns at local spatial scales, and particularly for ticks, transmitting the greatest diversity of recognized infectious agents. To test the degree to which ticks can disperse and disseminate pathogens at local scales, we investigated the temporal dynamics and population structure of the soft tick Ornithodoros maritimus within a colony of its seabird host, the Yellow-legged gull Larus michahellis. Ticks were repeatedly sampled at a series of nests during the host breeding season. In half of the nests, ticks were collected (removal sampling), in the other half, ticks were counted and returned to the nest. A subsample of ticks was screened for known bacteria, viruses and parasites using a high throughput real-time PCR system to examine their distribution within the colony. The results indicate a temporal dynamic in the presence of tick life stages over the season, with the simultaneous appearance of juvenile ticks and hatched chicks, but no among-nest spatial structure in tick abundance. Removal sampling significantly reduced tick numbers, but only from the fourth visit onward. Seven bacterial isolates, one parasite species and one viral isolate were detected but no spatial structure in their presence within the colony was found. These results suggest weak isolation among nests and that tick dispersal is likely frequent enough to quickly recolonize locally-emptied patches and disseminate pathogens across the colony. Vector-mediated movements at local scales may therefore play a key role in pathogen emergence and needs to be considered in conjunction with host movements for predicting pathogen circulation and for establishing effective control strategies.
de Parviez R. Hosseini, James N. Mills, Anne-Hélène Prieur-Richard, Vanessa O. Ezenwa, Xavier Bailly, Annapaola Rizzoli, Gerardo Suzán, Marion Vittecoq, Gabriel E. García-Peña, Peter Daszak, et al.
In Philosophical transactions of the Royal Society : biological sciences, 372(1722) (June 2017), 7
En ligne : rstb.royalsocietypublishing.org[...]
Biodiversity is of critical value to human societies, but recent evidence that biodiversity
may mitigate infectious-disease risk has sparked controversy among researchers. The majority of work on this topic has focused on direct assessments of the relationship between biodiversity and endemic-pathogen prevalence, without disentangling intervening mechanisms; thus study outcomes often differ, fuelling more debate. Here, we suggest two critical changes to the approach researchers take to understanding relationships between infectious disease,
both endemic and emerging, and biodiversity that may help clarify sources of controversy. First, the distinct concepts of hazards versus risks need to be separated to determine how biodiversity and its drivers may act differently on each. This distinction is particularly important since it illustrates that disease emergence drivers in humans could be quite different to the general relationship between biodiversity and transmission of endemic pathogens. Second, the interactive relationship among biodiversity, anthropogenic change and zoonotic disease risk, including both direct and indirect effects, needs to be recognized and accounted for. By carefully disentangling these interactions between humans’ activities and pathogen circulation in wildlife, we suggest that conservation
efforts could mitigate disease risks and hazards in novel ways that complement more typical disease control efforts. / Cet article rappelle la différence entre la présence d’une grande diversité de pathogènes, généralement liée à la diversité des hôtes et le risque pour la santé humaine qui n’y est pas forcément associé. En clair quand on conserve la biodiversité on conserve également la diversité des pathogènes qui jouent un rôle important dans les écosystèmes. Ces pathogènes ne posent problème que si l’homme y est sensible et exposé, ce risque augmentant en général quand nous perturbons les habitats. L’article détaille ces principes en se basant sur de nombreux exemples
de Salim Aberkane, Fabrice Compain, Dominique Decré, Alix Pantel, Marion Vittecoq, Jérôme Solassol, Nicolas Bouzinbi, Hélène Jean-pierre, Sylvain Godreuil
In Journal of Global Antimicrobial Resistance, 9 (06/2017), 138-140
En ligne : linkinghub.elsevier.com[...]
This study emphasises the persistence of multidrug resistance determinants in wild gulls, supporting our hypothesis that wild fauna may represent a zoonotic reservoir that may persist for several years without any known antibiotic selection pressure. Clonal analysis proves interspecies transmission with arising zoonotic risks in highly crowded areas.
VIM-1 carbapenemase-producing Escherichia coli in gulls from southern France
de Marion Vittecoq, Chrislène Laurens, Lionel Brazier, Patrick Durand, Eric Elguero, Audrey Arnal, Frederic Thomas, Salim Aberkane, Nicolas Renaud, Franck Prugnolle, et al.
In Ecology and Evolution, 7(4) (February, 2017), 1224-1232
En ligne : onlinelibrary.wiley.com[...]
Acquired carbapenemases currently pose one of the most worrying public health threats related to antimicrobial resistance. A NDM-1-producing Salmonella Corvallis was reported in 2013 in a wild raptor. Further research was needed to understand the role of wild birds in the transmission of bacteria resistant to carbapenems. Our aim was to investigate the presence of carbapenem-resistant Escherichia coli in gulls from southern France. In 2012, we collected 158 cloacal swabs samples from two gull species: yellow-legged gulls (Larus michahellis) that live in close contact with humans and slender-billed gulls (Chroicocephalus genei) that feed at sea. We molecularly compared the carbapenem-resistant bacteria we isolated through culture on selective media with the carbapenem-susceptible strains sampled from both gull species and from stool samples of humans hospitalized in the study area. The genes coding for carbapenemases were tested by multiplex PCR. We isolated 22 carbapenem-resistant E. coli strains from yellow-legged gulls while none were isolated from slender-billed gulls. All carbapenem-resistant isolates were positive for blaVIM-1 gene. VIM-1-producing E. coli were closely related to carbapenem-susceptible strains isolated from the two gull species but also to human strains. Our results are alarming enough to make it urgently necessary to determine the contamination source of the bacteria we identified. More generally, our work highlights the need to develop more bridges between studies focusing on wildlife and humans in order to improve our knowledge of resistant bacteria transmission routes./ : Nos équipes ont étudié les bactéries résistantes aux antibiotiques portées par deux espèces de goélands en Camargue.Elles ont ainsi découvert que les poussins de l’espèce pouvant vivre en ville, le goéland leucophée, peuvent être porteurs de bactéries capables de résister à des antibiotiques utilisés uniquement dans les hôpitaux : les carbapénèmes.Moustiques et maladies : histoire ancienne et nouvelles stratégies
de Marion Vittecoq, Benjamin Roche
In Zones Humides Infos, 92-93 (3ème-4ème trim. 2016), 7
En ligne : www.snpn.com[...]Toxoplasmosis and cancer: Current knowledge and research perspectives
de Marion Vittecoq, F. Thomas
In Bulletin de la société de pathologie exotique (Septembre 2016), 4 p.
En ligne : www.ncbi.nlm.nih.gov[...]
Toxoplasmosis, caused by Toxoplasma gondii, is one of the most prevalent parasitic diseases; it is estimated to affect a third of the world's human population. Many studies showed that latent toxoplasmosis may cause in some patients significant adverse effects including schizophrenia and bipolar disorders. In addition, two recent studies highlighted a positive correlation between the prevalence of brain tumors and that of T. gondii at national and international scale. These studies are correlative, thus they do not demonstrate a causal link between T. gondii and brain tumors. Yet, they call for further research that could shed light on the possible mechanisms underlying this association. / La toxoplasmose, causée par le protozoaire Toxo-plasma gondii , est une des parasitoses les plus répandues, puisqu ’ on estime qu’elle affecte un tiers de la population humaine mondiale. De nombreuses études tendent à démontrer que l ’ infection peut entraîner des effets néfastes importants tels que favoriser la schizophrénie et les troubles bipolaires. De plus, deux études ont récemment mis en évidence une corrélation positive entre la prévalence des tumeurs malignes du cerveau et celle des infections à T. gondii à l ’ échelle nationale et internationale. Ces études étant corrélatives, elles ne démontrent pas de lien causal et appellent d ’ autres recherches qui pourraient mettre en lumière les éventuels mécanismes qui sous-tendent l’association entre T. gondii et tumeurs cérébrales.Antimicrobial resistance in wildlife
de Marion Vittecoq, Sylvain Godreuil, Franck Prugnolle, Patrick Durand, Lionel Brazier, Nicolas Renaud, Audrey Arnal, Salim Aberkane, Hélène Jean-pierre, Michel Gauthier-Clerc, et al.
In Journal of Applied Ecology, 53(2) (April 2016), 519-529
En ligne : doi.wiley.com[...]
* The spread of antimicrobial resistance is of major concern for human health and leads to growing economic costs. While it is increasingly hypothesized that wildlife could play an important role in antimicrobial-resistant bacteria dynamics, empirical data remain scarce.
* The present work builds on a systematic review of the available data in order to highlight the main information we have and to suggest research pathways that should be followed if we aim to fill the gaps in our current knowledge.
* To achieve this goal, we address four questions: (i) Which resistant bacteria are the most frequently observed in wildlife? (ii) How are resistant bacteria exchanged between wildlife and the other hosts involved? (iii) In which habitats are those resistant bacteria found? (iv) Are resistances associated with certain ecological traits of the host?
* Synthesis and applications. We highlight the strong link existing between the impact of human activities on natural habitats and the carriage of antimicrobial-resistant bacteria by wildlife. Furthermore, we underline that omnivorous, anthropophilic and carnivorous species are at high risk of being carriers and potentially spreaders of antimicrobial-resistant bacteria. Identifying among those groups key sentinel species may be of particular interest to implement ecosystem contamination surveillance. Finally, we discuss possible exchange routes for antimicrobial-resistant bacteria between humans and wildlife. Considering that water is of major importance in those exchanges, a critical way to control antimicrobial resistance spread may be to limit aquatic environment contamination by antimicrobial-resistant bacteria and antibiotics.Cancer and life-history traits: lessons from host–parasite interactions
de Beata Ujvari, Christa Beckmann, Peter A. Biro, Audrey Arnal, Aurelie Tasiemski, Francois Massol, Michel Salzet, Frederic Mery, Celine Boidin-wichlacz, Dorothee Misse, et al.
In Parasitology, 143(5) (April 2016), 533-541
En ligne : www.journals.cambridge.org[...]
Despite important differences between infectious diseases and cancers, tumour development (neoplasia) can nonetheless be closely compared to infectious disease because of the similarity of their effects on the body. On this basis, we predict that many of the life-history(LH) responses observed in the context of host–parasite interactions should also be relevant in the context of cancer. Parasites are thought to affect LH traits of their hosts because of strong selective pressures like direct and indirect mortality effects favouring, for example, early maturation and reproduction. Cancer can similarly also affect LH traits by imposing direct costs and/or indirectly by triggering plastic adjustments and evolutionary responses. Here, we discuss how and why a LH focus is a potentially productive but under-exploited research direction for cancer research, by focusing our attention on similarities between infectious disease and cancer with respect to their effects on LH traits and their evolution. We raise the possibility that LH adjustments can occur in response to cancer via maternal/paternal effects and that these changes can be heritable to (adaptively) modify the LH traits of their offspring. We conclude that LH adjustments can potentially influence the transgenerational persistence of inherited oncogenic mutations in populations.
de Salim Aberkane, Fabrice Compain, Dominique Decré, Chloé Dupont, Chrislène Laurens, Marion Vittecoq, Alix Pantel, Jérôme Solassol, Christian Carrière, François Renaud, et al.
In Antimicrobial Agents and Chemotherapy, 60(2) (Februar), AAC.01654-15
En ligne : aac.asm.org[...]
The genetic structures involved in the dissemination of blaCMY-2 carried by Proteus mirabilis isolates recovered from different gull species in the South of France were characterized and compared to clinical isolates. blaCMY-2 was identified in P. mirabilis isolates from 27/93 yellow-legged gulls and from 37/65 slender-billed gulls. It was carried by a conjugative SXT/R391-like integrative and conjugative element (ICE) in all avian strains and in 3/7 human strains. Two clinical isolates had the same genetic background as six avian isolates.The guardians of inherited oncogenic vulnerabilities
de Audrey Arnal, Tazzio Tissot, Beata Ujvari, Leonard Nunney, Eric Solary, Lucie Laplane, François Bonhomme, Marion Vittecoq, Aurelie Tasiemski, François Renaud, et al.
In Evolution, 70(1) (January 2016), 1-6
En ligne : doi.wiley.com[...]
Similar to seemingly maladaptive genes in general, the persistence of inherited cancer-causing mutant alleles in populations remains a challenging question for evolutionary biologists. In addition to traditional explanations such as senescence or antagonistic pleiotropy, here we put forward a new hypothesis to explain the retention of oncogenic mutations. We propose that although natural defenses evolve to prevent neoplasm formation and progression thus increasing organismal fitness, they also conceal the effects of cancer-causing mutant alleles on fitness and concomitantly protect inherited ones from purging by purifying selection. We also argue for the importance of the ecological contexts experienced by individuals and/or species. These contexts determine the locally predominant fitness-reducing risks, and hence can aid the prediction of how natural selection will influence cancer outcomeFaune sauvage et antibiorésistances
de François Renaud, Marion Vittecoq
In la revue d’humanité et biodiversité (Octobre 2015), 84
En ligne : lucperino.com[...]
de Audrey Arnal, Anaïs Droit, Eric Elguero, Hugo Ducasse, Marta I. Sanchez, Thierry Lefevre, Dorothee Misse, Malia Bédèrina, Marion Vittecoq, Simon Daoust, et al.
In Frontiers in Ecology and Evolution, 3 (2015), 1-7
En ligne : www.frontiersin.org[...]
Hosts manipulated by parasites are profoundly altered organisms exhibiting a broad range of potential modifications. Exploring this multidimensionality is an emerging field. Previous studies have shown that the bird trematode Microphallus papillorobustus induces several behavioural changes in the gammarid Gammarus insensibilis. Knowing that aggregation behaviour and reduced activity levels are strategies that limit predation in other species of amphipods, we explored in this study these behavioural responses for infected and uninfected G. insensibilis in the presence of host and non-host predator olfactory cues (bird faeces and fish mucus). While uninfected individuals reduced their activity level in the presence of predator cues, infected individuals did not change their activity level in presence of aquatic bird faeces. We also studied the gammarid aggregation behaviour. Uninfected gammarids in clean water spent significantly more time in aggregates than did infected individuals. Among the uninfected individuals, the aggregation level tended to increase when bird faeces and fish mucus were added, but the difference was not significant. Among infected individuals, the level of aggregation was significantly increased only with the bird faeces. We discussed our results in the context of the literature on multidimensional manipulations, acknowledging that subtle differences between unparasitized and parasitized gammarids can also be by-products of manipulation on other traits.Evolutionary perspective of cancer: myth, metaphors, and reality
de Audrey Arnal, Beata Ujvari, Bernard Crespi, Robert A. Gatenby, Tazzio Tissot, Marion Vittecoq, Paul W. Ewald, Andreu Casali, Hugo Ducasse, Camille Jacqueline, et al.
In Evolutionary Applications, 8(6) (April 2015), 541-544
En ligne : onlinelibrary.wiley.com[...]
The evolutionary perspective of cancer (which origins and dynamics result from evolutionary processes) has gained significant international recognition over the past decade and generated a wave of enthusiasm among researchers. In this context, several authors proposed that insights into evolutionary and adaptation dynamics of cancers can be gained by studying the evolutionary strategies of organisms. Although this reasoning is fundamentally correct, in our opinion, it contains a potential risk of excessive adaptationism, potentially leading to the suggestion of complex adaptations that are unlikely to evolve among cancerous cells. For example, the ability of recognizing related conspecifics and adjusting accordingly behaviors as in certain free-living species appears unlikely in cancer. Indeed, despite their rapid evolutionary rate, malignant cells are under selective pressures for their altered lifestyle for only few decades. In addition, even though cancer cells can theoretically display highly sophisticated adaptive responses, it would be crucial to determine the frequency of their occurrence in patients with cancer, before therapeutic applications can be considered. Scientists who try to explain oncogenesis will need in the future to critically evaluate the metaphorical comparison of selective processes affecting cancerous cells with those affecting organisms. This approach seems essential for the applications of evolutionary biology to understand the origin of cancers, with prophylactic and therapeutic applications.
de Hugo Ducasse, Audrey Arnal, Marion Vittecoq, Simon P. Daoust, Beata Ujvari, Camille Jacqueline, Tazzio Tissot, Paul Ewald, Robert A. Gatenby, Kayla C. King, et al.
In Evolutionary Applications, 8(6) (April 2015), 527-540
En ligne : onlinelibrary.wiley.com[...]
For an increasing number of biologists, cancer is viewed as a dynamic system governed by evolutionary and ecological principles. Throughout most of human history, cancer was an uncommon cause of death and it is generally accepted that common components of modern culture, including increased physiological stresses and caloric intake, favor cancer development. However, the precise mechanisms for this linkage are not well understood. Here, we examine the roles of ecological and physiological disturbances and resource availability on the emergence of cancer in multicellular organisms. We argue that proliferation of ‘profiteering phenotypes’ is often an emergent property of disturbed, resource-rich environments at all scales of biological organization. We review the evidence for this phenomenon, explore it within the context of malignancy, and discuss how this ecological framework may offer a theoretical background for novel strategies of cancer prevention. This work provides a compelling argument that the traditional separation between medicine and evolutionary ecology remains a fundamental limitation that needs to be overcome if complex processes, such as oncogenesis, are to be completely understood.Interdisciplinarity and Infestious Diseases: an Ebola Case Study (2015)
de V. O. Ezenwa, A.-H. Prieur-richard, B. Roche, X. Bailly, P. Becquart, G. E. Garcia-pena, P. R. Hosseini, F. Keesing, A. Rizzoli, G. Suzan, et al.
2015
de Suzan G., Garcia-pena G., Castro-avellano I., Rico O., Rubio A., Tolsa M., Roche B., Hosseini P., Rizzoli A., Murray K., et al.
2015
de Marion Vittecoq, B. Roche, J.-M. Cohen, F. Renaud, F. Thomas, Michel Gauthier-Clerc
2015
de Audrey Arnal, E. Gomez-diaz, M. Cerda-cuellar, S. Lecollinet, J. Pearce-duvet, N. Busquets, I. Garcia-bocanegra, N. Pages, Marion Vittecoq
2014
de Audrey Arnal, Marion Vittecoq, J. Pearce-duvet, Michel Gauthier-Clerc, T. Boulinier, E. Jourdain
2014
de Marion Vittecoq, F. Thomas, E. Jourdain, F. Moutou, F. Renaud, Michel Gauthier-Clerc
2014Cancer: a missing link in ecosystem functioning? (2013)
de Marion Vittecoq, B. Roche, S. P. Daoust, H. Ducasse, D. Misse, J. Abadie, S. Labrut, F. Renaud, Michel Gauthier-Clerc, F. Thomas
2013
de Marion Vittecoq, S. Lecollinet, E. Jourdain, F. Thomas, Thomas Blanchon, Audrey Arnal, S. Lowenski, Michel Gauthier-Clerc
2013Brain cancer mortality rates increase with Toxoplasma gondii seroprevalence in France (2012)
de Marion Vittecoq, E. Elguero, K.D. Lafferty, B. Roche, J. Brodeur, Michel Gauthier-Clerc, D. Misse, F. Thomas
2012
de Marion Vittecoq, V. Grandhomme, Jocelyn Champagnon, Matthieu Guillemain, B. Crescenzo-chaigne, F. Renaud, F. Thomas, Michel Gauthier-Clerc, S. Van Der Werf
2012
de Marion Vittecoq
[S.l.] : Thèse doctorat: biologie de l'évolution et écologie: Université Montpellier 2, 2012, * 114p
de Marion Vittecoq, F. Thomas, E. Jourdain, F. Moutou, F. Renaud, Michel Gauthier-Clerc
2012Study of the influenza A virus in wild boars living in a major duck wintering site (2012)
de Marion Vittecoq, V. Grandhomme, G. Simon, S. Herve, Thomas Blanchon, F. Renaud, F. Thomas, Michel Gauthier-Clerc, S. Van Der Werf
2012Persistance des virus influenza A en fonction des paramètres environnementaux (2011)
de Marion Vittecoq, M. Ottmann, F. Renaud, F. Thomas, Michel Gauthier-Clerc
2011
de Michel Gauthier-Clerc, V. Grandhomme, C. Lebarbenchon, Marion Vittecoq, Yves Kayser, F. Renaud, F. Thomas, S. Van Der Werf
2010
