Le CEA et CISBIO-international créent le GIP sources HA, et révisent leur stratégie de gestion des sources scellées usagées

Pour répondre à leur obligation de reprises de sources scellées devenues sans emploi ou périmées, le CEA et CISBIO international ont, en 2009, créé le groupement d’intérêt public (GIP) sources HA qui a pour objet d’assurer la récupération, le conditionnement, ainsi que l’élimination des sources radioactives scellées de haute activité (SSHA), notamment de césium-137 et de cobalt-60, qu’ils ont fabriquées et distribuées en France. Le GIP peut également reprendre les sources orphelines de même nature, ce qui inclut les sources sans détenteur autorisé et les sources sans filière de reprise ou d’élimination. Afin de récupérer l’ensemble de ces sources d’ici 2016, le GIP souhaite entrer en contact avec les utilisateurs afin d’identifier leurs besoins et leurs intentions et de planifier le retour des sources. Parallèlement, CISBIO et le CEA continuent à assurer les mêmes missions pour les autres sources dont ils ont été fournisseurs ou fabricants. Seul, ou en partenariat, le GIP, CISBIO et le CEA souhaitent optimiser cette mission de service public : (1) en développant les services connexes rendus aux utilisateurs ou aux fournisseurs actuels, et (2) en déployant une stratégie d’élimination des sources destinée à écarter le risque de saturation des capacités d’entreposage

Uncertainties of the transfer of radionuclides in terrestrial ecosystems

The Nord-Cotentin radioecological study was conducted in different stages. First, an assessment tool was developed and implemented to estimate the number of leukaemia radio-induced by the operation of nuclear facilities of the La Hague site (Nord-Cotentin region, France). Then, an uncertainty analysis was initiated to verify if the confidence intervals around the best estimate previously calculated allows to confirm the low impact of the nuclear facilities. The modelling of the terrestrial ecosystems was especially studied because of the paucity of results of measurements. That is also why the methodology built to reconstruct the statistical laws for each parameter of the model mixes the bibliographic knowledge and exploitation of a national database of environmental measurements. The application of this methodology for up to forty parameters shows that the possibility of fitting an accurate distribution such as a normal or a lognormal law is strongly linked with the availability and the number of measured data

A study of the near field atmospheric dispersion of emissions at height: Comparison of Gaussian plume models (Doury, Pasquill-Briggs, Caire) with krypton 85 measurements taken around La Hague nuclear reprocessing plant

Gaussian atmospheric dispersion models are principally validated for release at ground level, or, if the release is very high up, at distances sufficiently removed from the source for the plume to have reached the ground. In order to improve the evaluation of the near field dispersion (< 4 km) for above-ground releases, the Institute for Protection and Nuclear Safety (IPSN) began an in situ study in June 1997 around the La Hague nuclear reprocessing plant using krypton 85 (85Kr, released in the gaseous effluent by a stack of 100 m high) as a plume tracer. The aim of this study is to compare the results for the atmospheric transfer coefficients (ATC) obtained in 85Kr measurement surveys with the results of three Gaussian atmospheric dispersion models (Doury, Pasquill-Briggs and CAIRE) in order to define the distances at which corrections need to be made to the models and thus improve determination of the ATCs. For all the results, it is observed as expected that the models are not applicable for the source near field; however, the study clearly shows that the CAIRE model gives the best results at all distances

Childhood encephalitis in the Greater Mekong region (the SouthEast Asia Encephalitis Project): a multicentre prospective study

Background Encephalitis is a worldwide public health issue, with a substantially high burden among children in southeast Asia. We aimed to determine the causes of encephalitis in children admitted to hospitals across the Greater Mekong region by implementing a comprehensive state-of-the-art diagnostic procedure harmonised across all centres, and identifying clinical characteristics related to patients’ conditions. Methods In this multicentre, observational, prospective study of childhood encephalitis, four referral hospitals in Cambodia, Vietnam, Laos, and Myanmar recruited children (aged 28 days to 16 years) who presented with altered mental status lasting more than 24 h and two of the following minor criteria: fever (within the 72 h before or after presentation), one or more generalised or partial seizures (excluding febrile seizures), a new-onset focal neurological deficit, cerebrospinal fluid (CSF) white blood cell count of 5 per mL or higher, or brain imaging (CT or MRI) suggestive of lesions of encephalitis. Comprehensive diagnostic procedures were harmonised across all centres, with first-line testing was done on samples taken at inclusion and results delivered within 24 h of inclusion for main treatable causes of disease and second-line testing was done thereafter for mostly non-treatable causes. An independent expert medical panel reviewed the charts and attribution of causes of all the included children. Using multivariate analyses, we assessed risk factors associated with unfavourable outcomes (ie, severe neurological sequelae and death) at discharge using data from baseline and day 2 after inclusion. This study is registered with ClinicalTrials.gov, NCT04089436, and is now complete. Findings Between July 28, 2014, and Dec 31, 2017, 664 children with encephalitis were enrolled. Median age was 4·3 years (1·8–8·8), 295 (44%) children were female, and 369 (56%) were male. A confirmed or probable cause of encephalitis was identified in 425 (64%) patients: 216 (33%) of 664 cases were due to Japanese encephalitis virus, 27 (4%) were due to dengue virus, 26 (4%) were due to influenza virus, 24 (4%) were due to herpes simplex virus 1, 18 (3%) were due to Mycobacterium tuberculosis, 17 (3%) were due to Streptococcus pneumoniae, 17 (3%) were due to enterovirus A71, 74 (9%) were due to other pathogens, and six (1%) were due to autoimmune encephalitis. Diagnosis was made within 24 h of admission to hospital for 83 (13%) of 664 children. 119 (18%) children had treatable conditions and 276 (42%) had conditions that could have been preventable by vaccination. At time of discharge, 153 (23%) of 664 children had severe neurological sequelae and 83 (13%) had died. In multivariate analyses, risk factors for unfavourable outcome were diagnosis of M tuberculosis infection upon admission (odds ratio 3·23 [95% CI 1·04–10·03]), coma on day 2 (2·90 [1·78–4·72]), supplementary oxygen requirement (1·89 [1·25–2·86]), and more than 1 week duration between symptom onset and admission to hospital (3·03 [1·68–5·48]). At 1 year after inclusion, of 432 children who were discharged alive from hospital with follow-up data, 24 (5%) had died, 129 (30%) had neurological sequelae, and 279 (65%) had completely recovered. Interpretation In southeast Asia, most causes of childhood encephalitis are either preventable or treatable, with Japanese encephalitis virus being the most common cause. We provide crucial information that could guide public health policy to improve diagnostic, vaccination, and early therapeutic guidelines on childhood encephalitis in the Greater Mekong region. Funding Institut Pasteur, Institut Pasteur International Network, Fondation Merieux, Aviesan Sud, INSERM, Wellcome Trust, Institut de Recherche pour le Développement (IRD), and Fondation Total. Translations For the Khmer, Lao, Vietnamese and Burmese translation of the abstract see Supplementary Materials section