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Urogenital schistosomiasis has been present naturally in the South of Europe since the beginning of the 20 th century and nowadays its presence is also known, at least imported by Sub-Saharan emigrants and tourists, in France, Italy, Portugal and Spain. One of the intermediate hosts of this trematode present in Europe is the bulinid mollusc Bulinus truncatus, non-native species that can be reached to Europe by humans and birds. In order to know this mollusc better, we carried out a morpho-anatomical study, of the shell, the reproductive system, radula, the respiratory organs and pseudobranch of several populations from Italy, France and Spain. Spanish conchological material studied comes from different populations, from material deposited in the "Museo Nacional de Ciencias Naturales" of Madrid and the "Museu de Ci{\`e}ncies Naturals" of Barcelona, as well as from its own material deposited in the "Museu Valenci{\`a} d'Hist{\`o}ria Natural" of Alginet (Valencia). The shell growth in captivity and the estimation of the population age of B. truncatus from El Ejido (Almer{\'i}a, Spain), has also been studied. Finally, the finding of aphallic and euphallic specimens in the different populations of southern Europe studied is presented and taxonomic and ecological data of the genus Bulinus are shown.

Additional file 1: Table S1. Distribution of the cox1 sequences analysed of Ae. albopictus and the corresponding 27 haplotypes they provided, according to their geographical origin.

Additional file 3: Text S1. Detailed descriptions of the diverse Rhodnius ecuadoriensis phenotypes.

Additional file 3: Table S3. Phenotypic diversity of Ae. albopictus from south-western Europe and Brazil. Landmark-based (LB) and outline based (OB) Mahalanobis distances (LB/OB) obtained with discriminant analysis between wing shapes of females and males.

Additional file 2: Table S2. Pairwise distances between cox1 nucleotide sequences of Ae. albopictus populations analysed according to PAUP.

International audience; Background: Global changes promote the spread of infectious diseases worldwide. In this context, tropical uro-genital schistosomiasis is now permanently established in Corsica since its first emergence in 2013. The local persistence of the tropical pathogens (schistosomes) responsible for urogenital schistosomiasis at such latitudes might be explained by (i) the presence of its intermediate host, the snail Bulinus truncatus, (ii) the recurrent local reseeding of schistosomes by their vertebrate hosts (either human or animal) every summer, and/or (iii) the maintenance and survival of schistosomes within their snail hosts over winter.Methods: In this study we conducted an ecological experiment to assess the ability of temperate and tropical schistosome strains to survive in classical winter temperatures in Corsican rivers when infecting temperate (local) snail strains. We also quantified the ability of the schistosomes to complete their life-cycle post-overwintering when returned to classical summer water temperatures.Results: Our results show that Mediterranean molluscs are locally adapted to winter conditions compared to tropical molluscs. Moreover, temperate and tropical schistosome strains equally survived the cold and produced viable offspring when returned to optimal temperatures. These results indicate that schistosomes can overwinter under temperate climates when infecting locally adapted snails and might partly explain the establishment and maintenance of schistosomes in Corsica from year to year.Conclusions: The observed broader thermal range of schistosomes compared to that of their snail hosts was unexpected and clearly indicates that the spread and establishment of schistosomiasis in temperate countries relies primarily on the presence of the locally adapted snail host lineages, currently known to be present in France, Italy, Portugal, Spain and Greece.

Schistosomes cause schistosomiasis, the world’s second most important parasitic disease after malaria. A peculiar feature of schistosomes is their ability to produce viable and fertile hybrids. Originally only present in the tropics, schistosomiasis is now also endemic in Europe. Based on two genetic markers the European species had been identified as a hybrid between the ruminant-infective Schistosoma bovis and the human-infective Schistosoma haematobium.

Lymnaeid shell measurements for natural populations of morphologically similar species, Lymnaea viator and Lymnaea neotropica from the present study and Galba truncatula, including t-test statistical comparison of variables of L. viator vs L. neotropica in Locality A. (PDF 67 kb)

High density of lymnaeids on mud and freshwater border in Locality A (village of Taton). (PDF 415 kb)

Freshwater habitats of lymnaeids. a-g Locality A: in villages of Taton and Rio Grande. h-j Locality B: in the neighbourhood of Ipizca. b Note general aridity. c Sand dunes in the background. b, d Closeness to human dwellings. g Lymnaeids present on mud. i Small artificial dyke on the river. (PDF 448 kb)

Systemic analysis is proposed in this manuscript as a tool to analyze the life-cycle and transmission of F. hepatica and F. gigantica. To be precise, chaos analysis of a temporary series of F. hepatica eggs shedding in murid (Wistar rats) faeces is used by means of Chaos Data Analyzer software with the aim to analyze the possible existence of attractors, sensibility to initial conditions and chaos.

International audience

This is a review of all known, new and already published data on the fauna of Helminths (Trematoda Digenea, Cestoda, Nematoda and Acanthocephala) parasitizing Rodents of the family Muridae (Mus musculus Linnaeus, 1758; Mus spretus Lataste, 1883; Rattus rattus Linnaeus, 1758; Rattus norvegic Berkenhout, 1769; and Apodemus sylvaticus Linnaeus, 1758) in Catalonia (Spain).

International audience

In the studies on the ecology of the parasite fauna of free living small mammals in Formentera (Balearic Islands) notable differences as regards similar works in other islands or in the continent were found. The particular qualitative and quantitative composition of the ectofauna and endofauna can be explained by the special phisiography of the island and the uncommon ecology of the definitive hosts (domination of the garden dormouse). On the basis of these investigations and of the data of the short literature dealing with the topic «parasitology in isolated ecosystems», it can be deduced a number of advantages and disadvantages offered by insular ecosystems in respect to parasitological research and finally the general interest of them.

La Fascioliasis y la Esquistosomiasis son dos importantes trematodiasis (re)emergentes con gran impacto en la salud humana. Dada la necesidad de caracterizar las poblaciones de Trematodos involucradas, los objetivos de la presente investigación son: en primer lugar, analizar el impacto de la reinfección experimental por Fasciola hepatica en los fenotipos inmunológicos, clínicos y biológicos por medio de un diseño experimental que reproduce las condiciones habituales de reinfección/cronicidad en las zonas endémicas de la Fascioliasis humana; en segundo lugar, la caracterización fenotípica morfológica de huevos de Schistosoma haematobium de migrantes subsaharianos con Esquistosomiasis urogenital en España y la presentación de una nueva metodología de estudio. Los resultados obtenidos se han agrupado en cuatro apartados. A. Impacto de la reinfección en Fascioliasis en la respuesta inmunitaria del hospedador: relación con los fenotipos clínicos de la anemia. Se analizó el perfil de los niveles de expresión de Th1/Th2/Th17/Treg después de la reinfección, correlacionándolos con sus correspondientes biomarcadores hematológicos de morbilidad. La reinfección en la fase crónica fue capaz de activar una respuesta inmune mixta (Th1/Th2/Th17/Treg). La respuesta inmunológica sistémica fue diferente en cada grupo, lo que sugiere que la supresión está mediada por diferentes mecanismos en cada caso. Se realizaron cinco modelos matemáticos multivariantes para describir los niveles de expresión de Th1/Th2/Th17/Treg y el fenotipo clínico. B. Impacto de la reinfección en Fascioliasis en la emisión de huevos de F. hepatica: relación con la respuesta inmunorreguladora. Se analizaron los niveles séricos de IgG1 y el contaje de huevos por gramo de heces (hpg) tras la reinfección, correlacionándolos con su correspondiente perfil de los niveles de expresión de citoquinas Th1/Th2/Th17/Treg. Se detectaron promedios transitoriamente más altos de hpg y hpg/parásito en los grupos reinfectados frente a los grupos primoinfectados (PI) en las semanas posteriores a la reinfección. Los hpg se correlacionaron con los niveles de IgG1 así como con los niveles de expresión sistémicos de Il10 y tímicos de Ifng e Il10. Estos resultados sugieren que la cantidad de hpg depende del fenotipo Th1 y Treg y que la determinación de la carga parasitaria por el conteo de hpg podría sobreestimarla en los casos de reinfección reciente. Se requiere un protocolo que facilite la aplicación de las técnicas de recuento por hpg y la consiguiente decisión sobre la dosis de tratamiento apropiada para cada paciente a fin de prevenir el riesgo de cólico. C. Análisis fenotípico de los huevos de tres especies de Schistosoma: propuesta de una metodología de estudio estandarizada. El presente estudio se centró en huevos considerados como S. haematobium puro por caracterización genética (secuenciación de la región ITS del ADNr y RD-PCR de cox 1 del ADNmt). Se realizó una caracterización fenotípica de los huevos de S. haematobium mediante comparación morfométrica con poblaciones experimentales de S. bovis y S. mansoni utilizando el Sistema de Análisis de Imágenes por Computadora (CIAS) aplicado sobre diecisiete nuevas medidas estandarizadas. El análisis de componentes principales (ACP) y el análisis canónico de la varianza (ACV) mostraron tres patrones fenotípicos en los huevos de S. haematobium, S. bovis y S. mansoni. En general, S. mansoni y S. bovis presentaron mayores distancias entre ellos que con S. haematobium. En cuanto a la espina, S. haematobium y S. mansoni fueron las especies más distantes. Los resultados muestran la utilidad de esta metodología para la diferenciación fenotípica de los huevos de estas especies de Schistosoma, capaces de discernir entre huevos morfológicamente cercanos, como es el caso del grupo haematobium. El fenotipado de huevos de esquistosoma podría aplicarse para evaluar no sólo las formas híbridas sino también la posible influencia de gran variedad de factores sobre el morfotipo de los huevos. D. Caracterización fenotípica de huevos de tipo S. haematobium y genéticamente puros: descripción de morfotipos y análisis de la influencia del origen geográfico en el fenotipo de los huevos. La metodología descrita anteriormente permitió clasificar huevos de S. haematobium obtenidos de muestras de migrantes subsaharianos en España en tres morfotipos: redondeados, alargados y con forma de huso o spindle. Los resultados muestran una distribución desigual de estos morfotipos entre los países. Además, una submuestra fue geno y fenotipada (secuenciación de la región ITS y RD-PCR de cox 1), lo que permitió comparar sólo los huevos puros y eliminar la variabilidad que los huevos híbridos podrían presentar. En cuanto a la influencia del origen geográfico, se ha observado una gran variabilidad intraespecífica entre los diferentes países analizados. Futuros estudios confirmarán estos resultados y la utilidad de esta herramienta para realizar estudios comparativos sobre la morfología de los huevos híbridos del género Schistosoma. Fascioliasis and Schistosomiasis are two major (re)emerging trematodiasis with large impact on human health. Given the necessity to characterize the Trematode populations involved, the aims of the present research are, first, analyze the impact of Fasciola hepatica experimental reinfection on immunological, clinical and biological phenotypes by means of an experimental design which reproduced the usual reinfection/chronicity conditions in human Fascioliasis endemic areas. Second, the morphological phenotypic characterization of parasite eggs from Schistosomiasis haematobium infected sub-Saharan migrants in Spain and introduction of a new study methodology. The specific results have been grouped into four parts. A. Impact of Fascioliasis reinfection on host immune response: relationship with the clinical phenotypes of anemia. The profile of the Th1/Th2/Th17/Treg expression levels is analyzed after reinfection, correlating them with their corresponding hematological biomarkers of morbidity. Reinfection in the chronic phase is able to activate a mixed immune response (Th1/Th2/Th17/Treg). The systemic immune response is different in each group, suggesting that suppression is mediated by different mechanisms in each case. Multivariate mathematical models were built to describe the Th1/Th2/Th17/Treg expression levels and the clinical phenotype. B. Impact of Fascioliasis reinfection on F. hepatica egg shedding: relationship with the immune‐regulatory response. Serical IgG1 levels and eggs per gram of feces (epg) were analyzed after reinfection, correlating them with their corresponding profile of the Th1/Th2/Th17/Treg expression levels. A transiently higher averages of epg and epg/worm in reinfected groups vs primoinfected group (PI) were detected at least in the weeks following reinfection. The kinetics of IgG1 levels shows that reinfected groups followed a pattern similar to the one in the PI group, but transiently higher averages of IgG1 levels in reinfected groups vs the PI group were detected in the weeks following reinfection. Epg correlated with IgG1 levels and also with systemic Il10 and thymic Ifng and Il10 expression levels. These results suggest that epg depends on the Th1 and Treg phenotype and that the determination of the fluke burden by epg is likely to be an overestimation in cases of recent reinfection in low burden situations. A strategy to facilitate the implementation of epg count techniques and the subsequent decision on the appropriate treatment dose for each patient to prevent colic risk is required. C. Phenotypic analysis of Schistosoma species eggs: proposal for a standardized study methodology. The present study focuses on eggs, considered genetically pure S. haematobium by genetic characterization (intergenic ITS region of the rDNA and cox 1 mtDNA by RD-PCR). A phenotypic characterization of S. haematobium eggs was made by morphometric comparison with experimental populations of S. bovis and S. mansoni. Analyses were made by Computer Image Analysis System (CIAS) applied on new standardized measurements and geometric morphometric tools. The principal component analysis (PCA), including seventeen nonredundant measurements, showed three phenotypic patterns in eggs of S. haematobium, S. bovis and S. mansoni. Mahalanobis distances between each pair of groups were calculated for each discriminant analysis performed. In general, S. mansoni and S. bovis present larger distances between them than with S. haematobium, i.e. they present the greatest differences. Regarding the spine, S. haematobium and S. mansoni are the most distant species. Results show the usefulness of this methodology for the phenotypic differentiation between eggs from these Schistosoma species, capable of discerning morphologically close eggs, as is the case of the haematobium group. Schistosoma egg phenotyping approaches may be applied to assess not only hybrid forms but also potential influences of a variety of other factors. D. Phenotypic characterization of S. haematobium‐like and genetically pure eggs: description of morphotypes and analysis of the influence of the geographical origin on egg phenotypes. The above-described methodology allowed us to classify the eggs from Schistosomiasis haematobium infecting sub-Saharan migrants in Spain into three morphotypes: round, elongated and spindle. The results show an uneven distribution of these morphotypes among countries. In addition, an egg sample was both geno- and phenotyped (intergenic ITS region of the rDNA and cox 1 mtDNA by RD-PCR), allowing us to compare only genetically pure eggs and eliminate the variability hybrid eggs might entail. Regarding the influence of the geographical origin, great intraspecific variation was found amongcountries. Further studies will confirm these results and the utility of this tool for comparative studies of hybrid Schistosoma egg morphology.

Fascioliasis is a highly pathogenic zoonotic disease caused by the liver trematodes Fasciola hepatica and F. gigantica. Within the multidisciplinary initiative against this disease, there is the aim of understanding how this disease reached a worldwide distribution, with important veterinary and medical repercussions, by elucidating the spreading steps followed by the two fasciolids from their paleobiogeograhical origins. Fasciola eggs were detected in paleofaeces of a donkey, probably the present-day endangered Persian onager Equus hemionus onager, found in the Chehrabad salt mine archaeological site, Zanjan province, northwestern Iran. The biological remains dated back to the Sassanid period, 224-651 AD. Egg characteristics allowed for their specific ascription to F. hepatica. The interest of this finding relies on the fact of being the first archaeological finding of Fasciola in Asia and the Near East. Moreover, it allows to reach many conclusions about historical, epidemiological and spreading aspects of the disease. The finding in Chehrabad indicates that, at that time, this fasciolid had already spread through the Zagros mountains eastward from the Fertile Crescent. In that region and in ancient Egypt, livestock domestication played a crucial role in facilitating the disease spread during the postdomestication period. Donkeys appear at present to be usually infected by fasciolids in countries of the Fertile Crescent - Ancient Egypt region or neighbouring that region, with prevalences from low to very high. The high pathogenicity and mortality induced by Fasciola in these equines should be considered as an additional potential factor among the causes of the extinctions of E. h. hemippus in Syria, E. h. hydruntinus in the Anatolia-Balkans area, E. h. onager in the Caucasus and maybe also its decline in Iran. Indeed, Eurasiatic wild asses were present in the region and neighbourhood of the Fertile Crescent when the domestication of the livestock reservoirs of Fasciola began.

La patogénesis de la fasciolosis depende de la carga parasitaria y del tamaño de los trematodos adultos. En zonas de hiperendemia, las intensidades individuales de parasitación humana pueden alcanzar niveles muy altos, estando la mayoría de los individuos parasitados en la fase de cronicidad avanzada. En este estudio se ha utilizado el modelo experimental de fasciolosis en rata Wistar por ser un modelo animal útil que mimetiza la fasciolosis crónica avanzada en humanos. Se ha infectado un total de 169 ratas con 20 metacercarias/rata vía oral, llevándose a cabo los siguientes análisis: A) Estudio la influencia de la intensidad individual de infección por rata (entendiendo la intensidad de infección como el número de trematodos por hospedador en el canal biliar principal) sobre: a) el desarrollo del adulto; b) el tiempo comprendido entre la ingestión de metacercarias y la presencia de huevos en heces (el periodo prepatente, pp) y c) el número de huevos por gramo de heces y por adulto (hgh/adulto). B) Estudio la influencia de la presencia de litiasis sobre el desarrollo del adulto. C) Estudio la influencia del género del hospedador definitivo experimental sobre la producción de huevos (hgh). Se ha calculado las trayectorias ontogenéticas de las siguientes medidas biométricas: área corporal (AC), perímetro corporal (P), anchura corporal (AnC) y longitud corporal (LoC). En los grupos analizados las trayectorias ontogenéticas de las medidas siguen un modelo logístico [y = ym / {1 + z0 exp (-kt)}, donde ym es el valor máximo al cual tiende la variable biométrica y; z0 y k = parámetros de las trayectorias; t= tiempo]. Los resultados obtenidos muestran que cuando el número de adultos aumenta, el valor de ym de estas medidas (AC, P, LoC y AnC) disminuye. El “crowding effect” se manifiesta cuando las medidas corporales del Trematodo adulto se aproximan a los valores máximos alcanzados en la fase de cronicidad avanzada. En las últimas fases de desarrollo, las tasas de crecimiento de las medidas corporales son más altas cuando menor es la carga parasitaria. El pp y los hgh/adulto se muestran dependientes del nivel de infección, disminuyendo cuando la carga parasitaria aumenta. Esto significa que el número de huevos por gramo de heces tiende a desestimar la carga parasitaria. En todas las medidas biométricas analizadas, los valores del tiempo en el punto de inflexión en el modelo logístico son similares a los datos empíricos sobre el pp, es decir, el momento donde empieza la emisión de huevos. Los resultados muestran que los adultos de F. hepatica alcanzan un menor desarrollo corporal cuando existe la presencia de litiasis concomitante en los conductos hepáticos. El estudio de la influencia del género del hospedador definitivo experimental revela que, en la fasciolosis crónica avanzada, en hembras Wistar (con una intensidad individual de infección de Trematodos adultos por rata similar a los machos) existe una mayor producción de hgh que en machos. Los resultados obtenidos muestran que la intensidad de infección, la litiasis y el género del hospedador definitivo son factores a tener en consideración cuando estudiamos el desarrollo de los adultos de F. hepatica en el modelo Wistar en la fase crónica avanzada. La consideración de estos factores es de interés tanto en estudios epidemiológicos, como en estudios experimentales in vivo sobre la acción de fármacos antihelmínticos y vacunas, patología, inmunología y resistencia., Fascioliasis pathogenesis depends on fluke burden and size. In human hyperendemic zones, individual infection intensities can reach very high levels being the majority of infected subjects in the advanced chronic phase. Wistar rat model has been used due to the fact it offers a useful approach for pathological research in the advanced chronic period in humans. 169 rats have been orally infected with 20 metacercariae/rat, developing the following tests: (i) influence of infection intensity per rat on fluke development (adult’s development, time between metacarcariae intake and presence of eggs in faeces, and number of eggs per gramme of faeces and adult); (ii) influence of lytiasis on the adult’s development; and (iii) influence of the experimental definitive host genus on egg production. Ontogenetic trajectories of fluke body measurements (AC, P, AnC and LoC), followed a logistic model. Results showed that (i) when burden increases, maximum values of fluke body measurements decrease; (ii) crowding effect is apparent when fluke measurements approximate their maximums in the advanced chronic stage; (iii) pre-patent period (pp) and egg production (hgh) decrease when fluke burden increases, meaning that measurements of eggs per gramme of faeces tend to underestimate the fluke burden; (iv) adults of F. hepatica reach a lower body development when concomitant lytiasis is observed in liver ducts; (v) when fasciolasis chronic stage, egg production is higher in Wistar rat females. Thus, intensity of infection, lytiasis and definitive host genus are factors to take into consideraction when studying the development of the adults of F. hepatica in Wistar model on an advanced fasciolasis chronic stage. This quantification may be of great interest in both, epidemiological studies and experimental research on the in vivo actions of different anthelminthic drugs and vaccines, pathology, immunology and resistance studies.