130 research outputs found

    Contacts and foot and mouth disease transmission from wild to domestic bovines in Africa

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    Wildlife is a maintenance host for several significant livestock diseases. Interspecific pathogen transmission may occur in complex socio-ecological systems at wild-domestic interfaces that have so far been seldom studied. We investigated the relationship between the dynamics of foot and mouth disease (FMD) in vaccinated and unvaccinated cattle populations with respect to frequency of contacts with African buffalo at different buffalo-cattle interfaces. A total of 36 GPS collars were deployed on African buffalo (Syncerus caffer) and cattle (Bos taurus, Bos indicus) to assess contact patterns at the periphery of 3 protected areas in Zimbabwe. Simultaneously, a longitudinal survey of 300 cattle with five repeated sampling sessions on known individuals during 16 months was undertaken. Immunological assays (ELISAs), that allowed tracking the production of antibodies following infection or vaccination, were used to assess serological transitions (i.e., incidence and reversion) in the surveyed cattle. Variation in rates of serological transitions across seasons, sites and as a function of the frequency of contact with buffalo was analyzed using generalized linear mixed models. The incidence in the cattle populations of FMD antibodies produced following infection varied among sites and as a function of contact rates with African buffalo. The incidence was higher for sites with higher contact rates between the two species. The serological incidence was also related to seasons, being higher during the dry or rainy seasons depending on sites. The reversion rate pattern was the opposite of this incidence rate pattern. Vaccination seemed partly efficient at the individual level, but it did not prevent the diffusion of FMD viruses from the wild reservoir host to the domestic cattle population. Furthermore, antibodies were detected in areas where cattle had not been vaccinated, suggesting that the virus may have spread without being detected in domestic populations. Access to resources shared by buffalo and livestock, particularly water and grazing areas during the dry season, could partly explain the observed patterns of FMD transmission. We discuss how insights on ecological processes leading to wildlife-livestock contacts may provide some innovative solutions to improve FMD management, including surveillance, prevention or control of buffalo-borne outbreaks, by adopting strategies targeting risky areas and periods. (Résumé d'auteur

    A 1.5 Ma Marine Record of Volcanic Activity and Associated Landslides Offshore Martinique (Lesser Antilles): Sites U1397 and U1399 of IODP 340 Expedition

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    The products of eruptive and mass-wasting processes that built island arc volcanoes are better preserved in marine deposits than on land. Holes U1397A and U1399A drilled during IODP Expedition 340 provide a 1.5 Ma record of the volcanic history of Martinique. 14C dating and δ18O patterns are used to reconstitute the chronostratigraphy of tephra, volcaniclastic turbidites, and mass-wasting events (traced by debris avalanches, debrites, and duplication and deformation of pre-existing sediments), leading to a new volcanic history of Montagne Pelée and Pitons du Carbet volcanoes. The top 50 m of core U1397A provides a continuous high-resolution sedimentation record over the last ∼130 ka. The sedimentation record deeper than 50 m in core U1397A and in the whole core U1399A is discontinuous because of the numerous sliding and deformation events triggered by debris avalanches related to flank collapses. Three successive activity periods are identified since ∼190 ka: the “Old Pelée” until 50 ka, the “Grand Rivière” (50–20 ka), and the “Recent Pelée” (20 ka—present day). The first two periods have the highest volcanic deposition rates offshore but very little outcrop on land. The whole magmatic activity of Mt Pelée comprises silicic andesites, but mafic andesites were also emitted during the whole “Grand Rivière.” At ∼115 ka, a major flank collapse (“Le Prêcheur”) produced a debris avalanche and submarine landslide that affected sea floor sediments by erosion and deformation up to ∼70 km from the shore. The Pitons du Carbet volcano was active from 1.2 Ma to 260 ka with numerous large flank collapses at a mean rate of 1 event every 100 ka. The average deposition rate of tephra fall offshore is much less than that at Mt Pelée. Our data show that correlations between the timing of large landslides or emission of mafic magmas and rapid sea level rise or lowstands suggested by previous studies are not systematic. The reconstituted chronostratigraphy of cores U1397A and U1399A provides the framework necessary for further studies of the magma petrology and production rates and timing of the mechanisms triggering flank collapses and related submarine landslides of Mt Pelée and Pitons du Carbet

    Acute bacterial prostatitis: heterogeneity in diagnostic criteria and management. Retrospective multicentric analysis of 371 patients diagnosed with acute prostatitis

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    <p>Abstract</p> <p>Background</p> <p>There is currently a lack of consensus for the diagnosis, investigations and treatments of acute bacterial prostatitis (AP).</p> <p>Methods</p> <p>The symptoms, investigations and treatments of 371 inpatients diagnosed with AP were analyzed through a retrospective study conducted in four departments – Urology (U), Infectious Diseases (ID), Internal Medicine (IM), Geriatrics (G) – of two French university hospitals.</p> <p>Results</p> <p>The cause of admission, symptoms, investigations and treatments depended markedly on the department of admission but not on the hospital. In U, patients commonly presented with a bladder outlet obstruction, they had a large imaging and functional check-up, and received alpha-blockers and anti-inflammatory drugs. In ID, patients were febrile and received longer and more appropriate antibiotic treatments. In G, patients presented with cognitive disorders and commonly had post-void urine volume measurements. In IM, patients presented with a wide range of symptoms, and had very diverse investigations and antibiotic regimen.</p> <p>Overall, a 3:1 ratio of community-acquired AP (CA-AP) to nosocomial AP (N-AP) was observed. Urine culture isolated mainly <it>E. coli </it>(58% of AP, 68% of CA-AP), with venereal agents constituting less than 1%. The probabilistic antibiotic treatments were similar for N-AP and CA-AP (58% bi-therapy; 63% fluoroquinolone-based regimen). For N-AP, these treatments were more likely to be inadequate (42% <it>vs. </it>8%, p < 0.001) and had a higher rate of bacteriological failure (48% <it>vs. </it>19%, p < 0.001).</p> <p>Clinical failure at follow-up was more common than bacteriological failure (75% versus 24%, p < 0.001). Patients older than 49 had more underlying urinary tract disorders and a higher rate of clinical failure (30% versus 10%, p < 0.0001).</p> <p>Conclusion</p> <p>This study highlights the difficulties encountered on a daily basis by the physicians regarding the diagnosis and management of acute prostatitis.</p
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