The experience of the discovery and management of endemic fluorosis from hydric origin in the North of Meuse department : history, critical evaluation and perspective

Il y a maintenant 40 ans, A. Forfert, un lanceur d’alerte observateur, émettait l’hypothèse que l’eau de trois villages du nord-meusien puisse contenir un élément responsable de la coloration de l’émail des enfants y résidant. Il a ainsi permis de découvrir la présence naturelle de fluor dans l’eau de la nappe alimentant plusieurs communes à des concentrations allant de 1,2 à 12 mg/L. Ceci a conduit à la réalisation d’enquêtes épidémiologiques sur les effets de cette exposition hydrique sur la santé des populations. En dehors des effets visibles sur la qualité de l’émail dentaire liée à l’intensité de l’exposition et de la diminution significative des caries dentaires en fonction de la dose cumulée de fluor, hydrique ou non, ingérée au cours de la vie, les effets sur le système osseux ont été limités et non pathologiques. Ceci est probablement lié à la diversité du régime alimentaire des personnes exposées. La réaction médiatique a été à l’époque quasi-inexistante, sans grande mobilisation, ce qui n’a pas permis de poursuivre les investigations sur le plan métabolique. Des mesures de mélange d’eaux ont alors permis de distribuer une eau d’alimentation de qualité satisfaisante pour ce paramètre.Forty years ago, A. Forfert, an observing whistleblower, expressed the hypothesis of the presence of an element responsible for the enamel coloration of children’s teeth in 3 villages located in the North of the Meuse department. This allowed for discovering the presence of natural fluorine in the ground water used by many villages as source of their drinking water with concentrations ranging from 1.2 to 12 mg/L. This led to conducting epidemiological studies on the health effects of this hydric exposure. Except for the visible effects on the dental enamel quality linked to the exposure intensity and the significant decrease of the DMFT index in relation with the cumulated dose of ingested fluorine (hydric and foodborne), only limited and not really pathological effects have been discovered on the musculoskeletal system. This was probably due to the variety of diet of the exposed people in this area. Media reaction was quite inexistent, as well as mobilization of the population, making it impossible to pursue more intensive metabolic studies. Remediation has been organized through mixture of waters from different origins allowing the distribution of drinking water in accordance with the regulation for fluorine concentration

Consensus report: E. coli O104:H4 (HUSEC041) and the potential threat to European water supplies.

Among the 3rd Seminar for PhD students working on Water and Health which was held in Cannes on 27–29 June 2011, experts from a number of universities and research institutes took the opportunity to discuss the emergence of Escherichia coli O104:H4 in Europe. Especially, possible threats for European water suppliers were considered. The consensus is summarized in this report. The main conclusion was that E. coli O104:H4 would not pose a substantial risk to well managed water supplies, especially where regular monitoring of indicator E. coli is negative. However, this may not apply for small and very small water systems which are quite common in Europe. New strategies like the Water Safety Plan approach are needed to protect also small scale drinking water systems and private wells in Europe. Water used in the processing of foods likely to be eaten raw, especially sprouts, should be of drinking water quality

Les processus de différenciation et la résistance des kystes aux traitements de désinfection chez l'amibe libre Vermamoeba vermiformis

V. vermiformis est une amibe libre répandue dans l'environnement et les milieux artificiels comme les réseaux d'eau chaude sanitaire (RECS). Il est maintenant bien établi qu'elle joue un rôle de réservoir pour des bactéries pathogènes, comme L. pneumophila. Le contrôle de V. vermiformis dans les RECS représente donc un enjeu sanitaire important. Les amibes libres peuvent passer d'une forme métaboliquement active (trophozoïte) à une forme de résistance, le kyste, lorsque les conditions sont défavorables ce qui leur confère une résistance aux traitements. Malgré la haute prévalence de V. vermiformis dans les RECS, les processus de différenciation et la résistance de ses kystes aux traitements n'ont été que peu étudiés. Nous avons donc investigué les changements morphologiques et ultrastructuraux qui s'opèrent lors de l'enkystement et désenkystement de V. vermiformis. Il en ressort que l'enkystement est un phénomène rapide (9 h) qui conduit à la formation de kystes entourés d'une paroi double couche. Lors du désenkystement, les trophozoïtes n'émergent pas à travers un ostiole comme c'est le cas chez Acanthamoeba. Puis, nous avons étudié l'effet des conditions environnementales et de la concentration cellulaire sur l'enkystement. Nous avons observé que plus la concentration cellulaire est élevée plus l'enkystement est rapide, ce qui suggère l'existence de mécanismes de communication intercellulaire. Enfin, nous avons étudié la résistance des kystes aux traitements utilisés dans les RECS et aux protéases. Ces traitements étaient efficaces, in vitro, pour inactiver les kystes de V. vermiformis. Ces travaux ont permis d'apporter des connaissances de bases sur les processus de dVermamoeba vermiformis is a free-living amoeba (FLA) widespread in the environment and artificial environments such as hot water networks. It is now well established that it acts as a reservoir for many pathogenic bacteria, such as Legionella pneumophila. The control of V. vermiformis in artificial environments represents an important health issue. FLA can turn from a metabolic active form (trophozoite) to a resistance form, called cyst, when conditions are unfavorable. Cysts are more resistant to treatments. Despite the high prevalence of V. vermiformis in hot water networks, the processes of differentiation and the resistance of cysts to disinfection treatments have been poorly studied. Therefore we investigated morphological and ultrastructural changes occurring during encystment and excystment of V. vermiformis. It appears that encystment is a fast process (9 h) which leads to the formation of cysts surrounded by a double-layered wall. During excystment, trophozoites do not emerge through an ostiole as is the case with Acanthamoeba. Then, we studied the effect of environmental conditions and cell concentration on encystment. We observed that the higher cell concentration was, the faster the encystment was, which suggests the existence of intercellular communication. Finally, we studied the resistance of cysts to conventional disinfection treatments used in hot water networks and to innovative treatment with proteases. These treatments were effective, in vitro, to inactivate V. vermiformis cysts. This work provides new finding regarding differentiation processes and cysts resistance of V. vermiformis, a free-living amoeba poorly studied.POITIERS-SCD-Bib. électronique (861949901) / SudocSudocFranceF

Antimicrobial resistance of Staphylococcus aureus, fecal streptococci, Enterobacteriaceae and Pseudomonas aeruginosa isolated from the coastal water of the Gaza strip-Palestine

Objectives: To document the occurrence and distribution of antibiotic resistance of clinically important bacteria in the seawater of Gaza strip-Palestine. Methods: Seawater samples were collected at 16 location distributed along the coast of the Gaza strip. Sampling was accomplished during 12 months, from March 2014 to June 2015. The microbial composition including Enterobacteriaceae, Staphylococcus aureus, fecal streptococci and Pseudomonas aeruginosa was recorded and tested for their resistance to specific antimicrobial agents according to CLSI using the disc diffusion method. Results: A total of 816 isolates of Enterobacteriaceae (377), S. aureus (29), fecal enterococci (FS)(369), and P. aeruginosa (29) were recovered and identified. Enterobacteriaceae, P. aeruginosa, FS and S. aureus isolates exhibited the highest rates of resistance against β-lactam drugs. The isolates also showed resistance to at least

Does microbicide use in consumer products promote antimicrobial resistance? A critical review and recommendations for a cohesive approach to risk assessment

The increasing use of microbicides in consumer products is raising concerns related to enhanced microbicide resistance in bacteria and potential cross resistance to antibiotics. The recently published documents on this topic from the European Commission have spawned much interest to better understand the true extent of the putative links for the benefit of the manufacturers, regulators, and consumers alike. This white paper is based on a 2-day workshop (SEAC-Unilever, Bedford, United Kingdom; June 2012) in the fields of microbicide usage and resistance. It identifies gaps in our knowledge and also makes specific recommendations for harmonization of key terms and refinement/standardization of methods for testing microbicide resistance to better assess the impact and possible links with cross resistance to antibiotics. It also calls for a better cohesion in research in this field. Such information is crucial to developing any risk assessment framework on microbicide use notably in consumer products. The article also identifies key research questions where there are inadequate data, which, if addressed, could promote improved knowledge and understanding to assess any related risks for consumer and environmental safety

Epidemiology of MRSA and current strategies in Europe and Japan

The prevalence of health-care associated infections caused by multi-drug resistant organisms has significantly increased over the past decade. Among these organisms, Methicillin-resistant Staphylococcus aureus (MRSA) plays a prominent and increasing role. Because of consequences for patients and the economic burden in course of prolonged treatment following MRSA infections and additional indirect costs for e.g. isolation or antiseptic treatment, this trend will further damage European health-care systems