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International audience; Progress in the diagnosis of leishmaniases depends on the development of effective methods and the discovery of suitable biomarkers. We propose firstly an update classification of Leishmania species and their synonymies. We demonstrate a global map highlighting the geography of known endemic Leishmania species pathogenic to humans. We summarize a complete list of techniques currently in use and discuss their advantages and limitations. The available data highlights the benefits of molecular markers in terms of their sensitivity and specificity to quantify variation from the subgeneric level to species complexes, (sub) species within complexes, and individual populations and infection foci. Each DNA-based detection method is supplied with a comprehensive description of markers and primers and proposal for a classification based on the role of each target and primer in the detection, identification and quantification of leishmaniasis infection. We outline a genome-wide map of genes informative for diagnosis that have been used for Leishmania genotyping. Furthermore, we propose a classification method based on the suitability of well-studied molecular markers for typing the 21 known Leishmania species pathogenic to humans. This can be applied to newly discovered species and to hybrid strains originating from inter-species crosses. Developing more effective and sensitive diagnostic methods and biomarkers is vital for enhancing Leishmania infection control programs.

International audience; BACKGROUND: Canine leishmaniasis (CanL), a parasitic zoonotic disease caused by Leishmania infantum and usually transmitted by phlebotomine sandflies, has rarely been reported in Pacific islands, which have been regarded until now as leishmaniasis-free territory. Here, we report the first autochthonous CanL case in New Caledonia (south-western Pacific) and the investigations carried out 1) to determine how infection was introduced into and transmitted among these dogs and 2) to assess the risks to animal and public health.METHODS: Extensive epidemiological and entomological investigations in and around the focus were carried out. Leishmaniasis infection was confirmed by histopathology, indirect fluorescent antibody test, real-time PCR, and culture. Parasite strain was typed by the isoenzymatic technique.RESULTS: The survey revealed close contacts between the autochthonous dog and two infected bitches imported from Spain, but failed to find any possible vector or disease spreading to other animals or humans. L. infantum zymodeme MON-1, the most frequent type in the Mediterranean basin, was identified. Although transplacental and venereal transmissions could not be excluded, the evidence was in favour of non-vectorial, direct dog-to-dog transmission.CONCLUSIONS: This study corroborates the possibility of non-vectorial routes (transplacental, venereal, and direct dog-to-dog) of canine leishmaniasis transmission in New Caledonia and raises the debate of relevant test requirements and diagnostic sensitivity prior to importation of dogs in Leishmania-free regions. New leishmaniasis control measures and recommendations to avoid future CanL introduction on the island are discussed.

International audience; Schmallenberg virus (SBV), a novel arboviral pathogen, has emerged and spread across Europe since 2011 inflicting congenital deformities in the offspring of infected adult ruminants. Several species of Culicoides biting midges (Diptera: Ceratopogonidae) have been implicated in the transmission of SBV through studies conducted in northern Europe. In this study Culicoides from SBV outbreak areas of mainland France and Italy (Sardinia) were screened for viral RNA. The role of both C. obsoletus and the Obsoletus complex (C. obsoletus and C. scoticus) in transmission of SBV were confirmed in France and SBV was also discovered in a pool of C. nubeculosus for the first time, implicating this species as a potential vector. While collections in Sardinia were dominated by C. imicola, only relatively small quantities of SBV RNA were detected in pools of this species and conclusive evidence of its potential role in transmission is required. In addition to these field-based studies, infection rates in colony-derived individuals of C. nubeculosus and field-collected C. scoticus are also examined in the laboratory. Rates of infection in C. nubeculosus were low, confirming previous studies, while preliminary examination of C. scoticus demonstrated that while this species can replicate SBV to a potentially transmissible level, further work is required to fully define comparative competence between species in the region. Finally, the oral competence for SBV of two abundant and widespread mosquito vector species in the laboratory is assessed. Neither Aedes albopictus nor Culex pipiens were demonstrated to replicate SBV to transmissible levels and appear unlikely to play a major role in transmission. Other vector competence data produced from studies across Europe to date is then comprehensively reviewed and compared with that generated previously for bluetongue virus.

To the Editor: The report of a human cutaneous leishmaniasis case acquired in Clairvaux-les-lacs (1) led us to carry out an investigation with the veterinary clinics in Jura Department, France. Clairvaux-les-lacs is a lakeside resort located in Jura, one of the areas in France with the coldest average temperatures, and is clearly located outside the usual leishmaniasis-endemic area. At least 31 cases of canine leishmaniasis were diagnosed by veterinary clinics in Jura during 2007–2011. Because these dogs were native of or traveled in the leishmaniasis-endemic area along the Mediterranean Sea, all veterinarians considered the infections as acquired outside Jura. Although phlebotomine sand flies have not been reported in Jura to date, Phlebotomus perniciosus sand flies, proven vectors of leishmaniasis, have been found in 2 areas neighboring Jura: Cote-d'Or and Saone-et-Loire (2,3). We have also recently caught P. mascittii sand flies, a species with an unknown vectorial competence, in the Swiss region of Jura, Alsace, Champagne-Ardennes, and Belgium. Therefore, the presence of sand flies in Jura, particularly in wet and milder microclimatic areas (as Clairvaux-les-lacs), is likely, and canine infections could have been acquired locally. A recent model predicted that new at-risk areas are mostly located in western France along the Atlantic coast (4). In accordance with this model, we report new foci of autochthonous canine leishmaniasis in Deux Sevres, Loire-Atlantique, and Loiret. Canine leishmaniasis cases contracted in the Rhine Valley in Germany (5) and the canine cases in Jura argue for a northeastern spread of the disease-endemic area along the Rhone-Rhine axis and mild microclimatic niches. Entomologic and serologic surveys will be carried out in summer 2012 in Jura to look for evidence of possible indigenous transmission of leishmaniasis. These data should supplement the current model of northern spread of leishmaniasis-endemic areas.

The diagnostic performance of a polymerase chain reaction assay (PCR) for monitoring the effectiveness of aceturate diminazene treatment was compared with those of an antibody-detection ELISA test and the buffy-coat technique using sheep experimentally infected with either savannahtype or forest-type Trypanosoma congolense or T. vivax. Within the period of infection, the PCR using specific savannah-type T. congolense primers showed a significant higher diagnostic sensitivity (p < 0.05) than the buffy-coat technique. Both techniques gave closed results for detecting forest-type T. congolense or T. vivax infections. Following trypanocidal treatment, the PCR showed that specific product disappeared definitively 1 or 2 days later in animals in which a decrease of the antibody level and a significant improvement of the red packed cell volume were observed. The occurrence of relapse infection was detected by the PCR in one animal infected by T. vivax on day 19 post-treatment and confirmed by the persistence and increasing antibody level whereas the buffy-coat technique detected parasites 42 days later. Then, the PCR signals remained positive on several occasions while parasitaemia was detected only two times. The application of PCR combined with the antibody detection appeared to provide a useful tool as compared to the buffy-coat technique for monitoring the effectiveness of trypanocidal treatment.