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The Alderney Race is assumed to have the largest tidal-stream energy potential in the north-western European coastal seas. Interaction of the powerful tidal stream with strong wind, high waves and irregular bathymetry creates hydrodynamic conditions of extreme complexity, with high levels of turbulence. A comprehensive dataset has been created to improve the understanding of physical processes, turbulence, tidal stream and resource variability at the site. The database contains a large amount of oceanographic and meteorological measurements acquired in Alderney Race in 2017-2018. This exceptionally long period of observations (nearly one year) became possible due to modern tools and strategies of data acquisition. The paper presents some significant results from the database analysis. Among many results, we would like to underline the following: (i) a wide range of variability of mean flow and sea state parameters was documented; (ii) exceptionally large values of current velocity (7 m s -1 ) and significant wave height (8 m) were measured during extreme meteorological conditions; (iii) high-frequency variability of current speed during storm events was also found to be very large, with the standard deviation of velocity reaching 0.3 m s -1 in the bottom boundary layer, and 0.6 m s -1 in the surface layer; and (iv) predominant wind and wave direction relative to the flow impacts the wave height and significantly increases the turbulence kinetic energy of the flow. To our knowledge, this is the largest multi-variable database available on potential tidal energy sites. The results of database analysis can represent a significant advance in environmental conditions and resource characterization and provide advanced information to turbine developers. This article is part of the theme issue 'New insights on tidal dynamics and tidal energy harvesting in the Alderney Race'.

Tritium concentrations in oceans were compiled from the literature, online databases and original measurements in order to determine the global distribution of tritium concentrations according to latitude and depth in all oceans. The total inventory of tritium decay corrected in 2016 has been estimated using evaluation of the natural and artificial contributions in 23 spatial subdivisions of the total ocean. It is determined equal to 26.8 ± 14 kg including 3.8 kg of cosmogenic tritium. That is in agreement with the total atmospheric input of tritium from nuclear bomb tests and the natural inventory at steady-state estimated from natural production rates in the literature (27.8-29.3 kg in the Earth). We confirm the global increase in tritium according to latitude observed in the Northern hemisphere since 1967 with a maximum in the Arctic Ocean. The minimum tritium concentrations observed in the Southern Ocean were close to steady-state with known natural tritium deposition. We focused on the temporal evolution of surface (0 to 500 m) tritium concentrations in a selected area of the North Atlantic Ocean (30°N-60°N) where we found the 2016 concentration to be 0.60 ± 0.10 TU (1σ). Results showed that in that area, between 1988 and 2013, tritium concentrations: i) decreased faster than the sole radioactive decay, due to a mixing with lower and lateral less concentrated waters, and ii) decreased towards an apparent steady state concentration. The half-time mixing rate of surface waters and the steady state concentration were respectively calculated to be 23 ± 5 years (1σ) and 0.38 ± 0.07 TU (1σ). This apparent steady-state concentration in the North Atlantic Ocean implies a mean tritium deposition of 1870 ± 345 Bq·m -2 (1σ), five folds higher than the known inputs (natural, nuclear tests fallout and industrial releases, ~367 Bq·m -2 ) in this area., (Copyright © 2018 Elsevier B.V. All rights reserved.)

In this paper, a dynamic compartment model with a high temporal resolution has been investigated to describe tritium transfer in grassland ecosystems exposed to atmospheric 3 H releases from nuclear facilities under normal operating or accidental conditions. TOCATTA-χ model belongs to the larger framework of the SYMBIOSE modelling and simulation platform that aims to assess the fate and transport of a wide range of radionuclides in various environmental systems. In this context, the conceptual and mathematical models of TOCATTA-χ have been designed to be relatively simple, minimizing the number of compartments and input parameters required. In the same time, the model achieves a good compromise between easy-to-use (as it is to be used in an operational mode), explicative power and predictive accuracy in various experimental conditions. In the framework of the VATO project, the model has been tested against two-year-long in situ measurements of 3 H activity concentration monitored by IRSN in air, groundwater and grass, together with meteorological parameters, on a grass field plot located 2 km downwind of the AREVA NC La Hague nuclear reprocessing plant, as was done in the past for the evaluation of transfer of 14 C in grass. By considering fast exchanges at the vegetation-air canopy interface, the model correctly reproduces the observed variability in TFWT activity concentration in grass, which evolves in accordance with spikes in atmospheric HTO activity concentration over the previous 24 h. The average OBT activity concentration in grass is also correctly reproduced. However, the model has to be improved in order to reproduce punctual high concentration of OBT activity, as observed in December 2013. The introduction of another compartment with a fast kinetic (like TFWT) - although outside the model scope - improves the predictions by increasing the correlation coefficient from 0.29 up to 0.56 when it includes this particular point. Further experimental investigation will be undertaken by IRSN and EDF next year to better evaluate (and properly model) other aspects of tritium transfer where knowledge gaps have been identified in both experimental and modelling areas., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

[This corrects the article DOI: 10.1371/journal.pone.0172442.].

The Fukushima Daï-ichi nuclear power plant (FDNPP) accident resulted in radioactive Cs being discharged into the local marine environment. While Cs bioaccumulates in biota and slowly depurates, the Cs concentrated in biota constitutes a source of Cs for animals feeding on each other. The marine biota therefore serves as a pool that recycles Cs, and this recycling process delays depuration in the fish feeding on this biota pool. Because the continental shelf is squeezed between the coast and very deep sea, the demersal marine species are confined to a narrow strip along the coast, close to the source of the radioactive input. Unlike demersal species, however, pelagic species are not restricted to the most contaminated area but instead spend some, if not most, of their time and feeding off-shore, far from the input source. We suggest that the feeding pathway for fish is a box whose size depends on their mobility, and that this feeding box is much larger and less contaminated (because of dilution through distance) for pelagic fish than for demersal fish. The aim of this paper is to test this hypothesis and to propose a simple operational model implementing two transfer routes: from seawater and from feeding. The model is then used to match the observational data in the aftermath of the FDNPP accident.

Tritium ( 3 H) is mainly released into the environment by nuclear power plants, military nuclear facilities and nuclear reprocessing plants. The construction of new nuclear facilities in the world as well as the evolution of nuclear fuel management might lead to an increase of 3 H discharges from the nuclear industry. The VATO project was set up by IRSN (Institut de Radioprotection et de Sûreté Nucléaire) and EDF (Electricité de France) to reduce the uncertainties in the knowledge about transfers of 3 H from an atmospheric source (currently releasing HT and HTO) to a grassland ecosystem. A fully instrumented technical platform with specifically designed materials was set up downwind of the AREVA NC La Hague reprocessing plant (Northwest of the France). This study, started in 2013, was conducted in four main steps to provide an hourly data set of 3 H concentrations in the environment, adequate to develop and/or validate transfer models. It consisted first in characterizing the physico-chemical forms of 3 H present in the air around the plant. Then, 3 H transfer kinetics to grass were quantified regarding contributions from various compartments of the environment. For this purpose, an original experimental procedure was provided to take account for biases due to rehydration of freeze-dried samples for the determination of OBT activity concentrations in biological samples. In a third step, the 3 H concentrations measured in the air and in rainwater were reconstructed at hourly intervals. Finally, a data processing technique was used to determine the biological half-lives of OBT in grass., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The Fukushima nuclear accident resulted in the largest ever accidental release of artificial radionuclides in coastal waters. This accident has shown the importance of marine assessment capabilities for emergency response and the need to develop tools for adequately predicting the evolution and potential impact of radioactive releases to the marine environment. The French Institute for Radiological Protection and Nuclear Safety (IRSN) equips its emergency response centre with operational tools to assist experts and decision makers in the event of accidental atmospheric releases and contamination of the terrestrial environment. The on-going project aims to develop tools for the management of marine contamination events in French coastal areas. This should allow us to evaluate and anticipate post-accident conditions, including potential contamination sites, contamination levels and potential consequences. In order to achieve this goal, two complementary tools are developed: site-specific marine data sheets and a dedicated simulation tool (STERNE, Simulation du Transport et du transfert d'Eléments Radioactifs dans l'environNEment marin). Marine data sheets are used to summarize the marine environment characteristics of the various sites considered, and to identify vulnerable areas requiring implementation of population protection measures, such as aquaculture areas, beaches or industrial water intakes, as well as areas of major ecological interest. Local climatological data (dominant sea currents as a function of meteorological or tidal conditions) serving as the basis for an initial environmental sampling strategy is provided whenever possible, along with a list of possible local contacts for operational management purposes. The STERNE simulation tool is designed to predict radionuclide dispersion and contamination in seawater and marine species by incorporating spatio-temporal data. 3D hydrodynamic forecasts are used as input data. Direct discharge points or atmospheric deposition source terms can be taken into account. STERNE calculates Eulerian radionuclide dispersion using advection and diffusion equations established offline from hydrodynamic calculations. A radioecological model based on dynamic transfer equations is implemented to evaluate activity concentrations in aquatic organisms. Essential radioecological parameters (concentration factors and single or multicomponent biological half-lives) have been compiled for main radionuclides and generic marine species (fish, molluscs, crustaceans and algae). Dispersion and transfer calculations are performed simultaneously on a 3D grid. Results can be plotted on maps, with possible tracking of spatio-temporal evolution. Post-processing and visualization can then be performed., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The aim of this work was to study the near-field dispersion of (85)Kr around the nuclear fuel reprocessing plant at La Hague (AREVA NC La Hague - France) under stable meteorological conditions. Twenty-two (85)Kr night-time experimental campaigns were carried out at distances of up to 4 km from the release source. Although the operational Gaussian models predict for these meteorological conditions a distance to plume touchdown of several kilometers, we almost systematically observed a marked ground signal at distances of 0.5-4 km. The calculated atmospheric transfer coefficients (ATC) show values (1) higher than those observed under neutral conditions, (2) much higher than those proposed by the operational models, and (3) higher than those used in the impact assessments., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

After becoming a military doctor at the behest of his father, Ronald Ross was destined to make a discovery of paramout importance, i.e., malaria transmission through mosquito bites. This landmark discovery that was the fruit of a combination of curiosity, tenacity and luck, earned him the Nobel Prize in Medicine.

Events ongoing in the thymus are critical for deleting developing thymocytes specific for tissue antigens, and establishing self-tolerance within the T cell compartment. Aberrant thymic negative selection, however, is believed to generate a repertoire with increased self-reactivity, which in turn can contribute to the development of T cell-mediated autoimmunity. In this review, mechanisms that regulate the efficacy of negative selection and influence the deletion of autoreactive thymocytes will be discussed.

Klebsiella pneumoniae resistant to ceftazidime was isolated from ten neonates hospitalised between February and March 2006 in two Antananarivo hospitals, Madagascar. The main environmental source, for one hospital in particular, was the liquid used to rinse aspiration tubes in the paediatric wards. The risk of contamination from aspiration tubes is very high in the hospitals of Antananarivo since tap water used to rinse the tubes is not regularly changed. Phenotypical (biotyping and antibiotyping) and genotypical (pulsed-field gel electrophoresis) analysis of all the clinical isolates indicated that nine cases were due to a single clone. This clone carried the genes encoding SHV-2 and CTX-M-15 beta-lactamases. This is the first description of an epidemic due to an ESBL-producing member of the family Enterobacteriaceae in Malagasy hospitals.

Background: Chikungunya virus (CHIKV), an arbovirus, is responsible for a two-stage disabling disease, consisting of an acute febrile polyarthritis for the first 10 days, frequently followed by chronic rheumatisms, sometimes lasting for years. Up to now, the pathophysiology of the chronic stage has been elusive. Considering the existence of occasional peripheral vascular disorders and some unexpected seronegativity during the chronic stage of the disease, we hypothesized the role of cryoglobulins., Methods: From April 2005 to May 2007, all travelers with suspected CHIKV infection were prospectively recorded in our hospital department. Demographic, clinical and laboratory findings (anti-CHIKV IgM and IgG, cryoglobulin) were registered at the first consultation or hospitalization and during follow-up., Results: Among the 66 travelers with clinical suspicion of CHIKV infection, 51 presented anti-CHIKV IgM. There were 45 positive with the serological assay tested at room temperature, and six more, which first tested negative when sera were kept at 4 degrees C until analysis, became positive after a 2-hour incubation of the sera at 37 degrees C. Forty-eight of the 51 CHIKV-seropositive patients were screened for cryoglobulinemia; 94% were positive at least once during their follow-up. Over 90% of the CHIKV-infected patients had concomitant arthralgias and cryoglobulinemia. Cryoglobulin prevalence and level drop with time as patients recover, spontaneously or after short-term corticotherapy. In some patients cryoglobulins remained positive after 1 year., Conclusion: Prevalence of mixed cryoglobulinemia was high in CHIKV-infected travelers with long-lasting symptoms. No significant association between cryoglobulinemia and clinical manifestations could be evidenced. The exact prognostic value of cryoglobulin levels has yet to be determined. Responsibility of cryoglobulinemia was suspected in unexpected false negativity of serological assays at room temperature, leading us to recommend performing serology on pre-warmed sera.

Visceral leishmaniasis is present in 61 countries but 90% of the 500,000 new cases that arise annually occur in five countries, i.e., India, Bangladesh, Nepal, Sudan, and Brazil. Annual mortality is approximately 59000 cases. Agents based on pentavalent antimony have been the mainstay of treatment for the last 60 years. In recent years, however, clinical resistance to these agents has been reported especially in the state of Bihar in India. Pentamidine and amphotericin B were introduced in the 1950s and 1960s. More recent additions to the therapeutic arsenal include liposomal amphotericin B, miltefosine, and paromomycin. Among these recent molecules, miltefosine, i.e., the only oral agent, appears most vulnerable because it involves long-term treatment and has a long half-life. The main therapeutic problems now being encountered are the emergence of acquired resistance to antimonials, the high cost of treatment, and failure of therapy in immunocompromised patients mainly due to concurrent human immunodeficiency virus (HIV) infection. For eradication initiatives such as the one aimed at eliminating leishmaniasis on the Indian subcontinent, the appearance of drug resistance increases the risk associated to parasite infection and, as for malaria, tuberculosis and HIV infection, raises fears that the problems in the implementation of public health policies will lead to highly refractory forms.

A total of 248 Plasmodium falciparum isolates were sampled in travelers with malaria who came to Marseille, France from Comoros to investigate in vitro activities of antimalarial drugs and molecular markers of drug resistance. Of the 248 isolates, 126 were maintained in culture. Of these, 53% were resistant to chloroquine, and 3% had reduced susceptibility to quinine, mefloquine, and atovaquone; 1% had reduced susceptibility to halofantrine and dihydroartemisinin; 7% had reduced susceptibility to monodesethylamodiaquine; 37% had reduced susceptibility to cycloguanil; and none had reduced susceptibility to lumefantrine. Resistance-associated point mutations were screened in 207 isolates. No mutations in the cytochrome b gene were found. Of the 207 isolates, 119 (58%) had a mutation in the P. falciparum dihydrofolate reductase (Pfdhfr) gene at codon 108, 6 (5%) had mutations in both Pfdhfr codon 108 and the P. falciparum dihydropteroate synthase codon 437, and 115 (56%) had the chloroquine resistance-associated K76T mutation in the P. falciparum chloroquine resistance transporter gene. This study represents a unique opportunity to improve surveillance of P. falciparum drug resistance in Comoros with consequences for treatment and chemoprophylaxis guidelines.

We report on two patients with myeloid disorders and complex karyotypes including a dicentric chromosome, dic(17;20)(p11.2;q11.2), resulting in the loss of most of 17p and 20q. The presence of the centromeres of chromosomes 17 and 20 in the dic(17;20), as well as the loss of TP53, were confirmed by fluorescence in situ hybridization. Deletions of 17p and 20q are recurrent abnormalities in hematologic disorders, particularly myelodysplastic syndrome and acute myeloid leukemia). However, a dic(17;20) is an uncommon finding. According to the few reports in the literature, dic(17;20) is associated with an unfavorable prognosis. The key mechanism might be the loss of TP53 as well as other tumor suppressor genes in 20q that may have a critical role in tumor genesis.

Zoonosis is the cause of the vast majority of emerging diseases. Bats that occupy the second place in the mammal class play an important role. Whether they belong to the microchiroptera suborder or to the megachiroptera suborder, bats on all five continents have been implicated in transmission of numerous pathogens including not only viruses such as Lyssavirus (e.g. rabies), Hepanivirus (e.g. Hendra and Nipah virus) and recently coronavirus (e.g. SARS-like coronavirus and Ebola virus) but also fungus such as histoplasmosis. By modifying environmental conditions and encroaching on their biotope, human intervention has probably contributed to the introduction of chiropteras into an epidemiologic chain in which they previously had no place, thus promoting the emergence of new pathogens.

Malaria is a parasitological emergency requiring safe quick accurate diagnosis so that appropriate therapy can be implemented. A number of rapid diagnostic tests based on detection of HRP2 Ag, enzymes, LDH or aldolase are now available. However the use of these tests is restricted to trained, experienced staff in special situations. The purpose of this report is to describe the different tests on the market and clarify the limitations for their use.

In 2001, an outbreak of typhoid fever occurred among the members of the French Armed Forces. All had received a typhoid vaccination as per the immunization schedule practiced in the Armed Forces (every 5 years). A retrospective cohort study was conducted in 94 personnel. The objectives were to confirm the diagnosis, determine the source of contamination and identify the factors associated with defective vaccinal efficacy. Twenty-four cases were clinically identified. A cucumber salad was identified as the contaminating dish (Risk Ratio = 3.6; 95%CI 1.5-8.9). Only one factor was related to defective vaccinal efficacy; the risk of typhoid fever was two-fold higher in people vaccinated more than 3 years previously (Risk Ratio = 2.2; 95%CI, 1.1-4.2). Compliance with food hygiene rules could have prevented 24 cases of typhoid fever. Nevertheless, repeat vaccination against typhoid fever is now conducted every 3 years in the French Forces, in compliance with the manufacturers' recommendations.

The purpose of this retrospective analysis was to evaluate the outcome of pentamidine isethionate treatment (4 mg/kg of Pentamidine by the intramuscular route on Days 1 and 3) of cutaneous leishmaniasis in 326 cases that occurred during an outbreak among French military personnel in French Guyana from 1998 to 1999. A great difference was found between the 205 patients treated in French Guyana (series G) and 32 patients treated at the Laveran Military Hospital in Marseille, France (series L). Failure rate, i.e. 25% in series L versus 5% in series G, was significantly correlated with the delay to treatment which was much longer in series L. Extensive rhabdomyolysis was observed in all cases tested: this side-effect has not been reported. Based on these findings and a review of the literature on pentamidine isethionate, the authors recommend prompt treatment using lower doses. Other treatment alternatives for American cutaneous leishmaniasis are also presented including two of the latest developments in the field, i.e., oral treatment using miltefosine and topical treatment using agents such as paromomycine.

We identified an unusual strain of mycobacteria from two patients with pulmonary tuberculosis by its smooth, glossy morphotype and, primarily, its genotypic characteristics. Spoligotyping and restriction fragment length polymorphism typing were carried out with the insertion sequence IS6110 patterns. All known cases of tuberculosis caused by Mycobacterium canetti have been contracted in the Horn of Africa.

Objectives: Monitor the evolution in France of antibiotic sensitivity of non-typhoid salmonella isolated in fecal cultures conducted in army hospital laboratories., Methods: A prospective study was performed from January 1998 to December 1999 in all the biology departments of the 11 army hospitals in France. All the non-repetitive strains were sent to an official center for serotyping and determination of the minimum inhibiting concentrations, by dilution in Mueller Hinton's gelose. The antibiotics currently used in treatment were tested and interpretation endpoints followed the recent recommendations of the Antibiogram committee of the French society of microbiology. Identification of beta-lactamase was conducted by iso-electric focalization and polymerization by chain reaction (PCR). For Salmonella Typhimurium, research for the specific resistance locus of the DT104 clone was made using PCR., Results: Two hundred and twenty-two non-repetitive salmonella strains were isolated. The principle serotypes found were: Salmonella Enterididis (23.9%), S. Typhimurium (21.2%) and S. Hadar (10.8%). All the strains were sensitive to ciprofloxacin and cefotaxim, whereas one third exhibited reduced sensitivity to aminopenicillin. Depending on the serotype, Typhimurium and Hadar serotypes exhibited significantly lesser sensitivity to aminopenicillin, nalidixic acid and tetracycline. For S. Typhimurium, resistance is related to the diffusion of the multiresistant DT104 clone, which involves half of the strains of this serotype. For S. Hadar, 18 out of 24 strains (75%) were resistance to nalidixic acid, and 5 of them exhibited reduced resistance to ciprofloxacin. There was no difference in sensitivity to antibiotics between the strains responsible for diarrhea and those isolated in systematic examinations for capacity to work in the food trade (respectively 54 and 46% of strains)., Conclusion: Non-typhoid salmonella are frequently isolated in diarrhea of infectious origin. The increasing resistance to antibiotics is primarily related to the diffusion of the DT104 clone, regarding S. Typhimurium and to the increase in resistance to quinolone, regarding S. Hadar.

This richly illustrated article (80 color photographs) based on the authors' experience in French Guyana documents the clinical diversity of American tegumentary leishmaniasis. Main highlights include the often outstanding aspect of lesions, the high frequency of forms not associated with ulceration or scab formation that must be recognized to achieve diagnosis in travellers returning from endemic zones, and the special prognosis of clinical forms associated with intradermic, lymphatic or hematogenous spread. The article also reviews an original diagnostic method based on culture of cutaneous biopsy specimens on specific nutrient mediums that provides isolates in a high percentage of cases (80%) and thus allows identification of offending parasite.

Most outbreaks of noscomial infection are detected by means of molecular biological testing. However Euclidian distance is a rapid, reliable alternative if facilities for molecular biological testing are unavailable, as at the Principal Hospital in Dakar, Senegal. Over the 7 month period from 01/10/98 to 31/04/99, 110 of the 1033 blood cultures specimens collected in a group of 2360 children hospitalized in pediatric departments A and B of the Principal Hospital were found to be positive for Burkholderia cepacia. This high incidence suggested the possibility of an epidemic. This likelihood was further increased by evidence showing that all strains exhibited the same biotype and by results of pulsed-field electrophoresis (CHEF Mapper, Spel digestion) indicating that bacteria was of clonal origin. These findings were entirely consistent with those obtained by Euclidian distance but excessive mortality was not observed in the children involved. Testing of environmental specimens demonstrated the presence of the same strains in respirators and catheters. The most feasible hypothesis to account for these findings is environmental contamination resulting in mucocutaneous contamination of patients. Hemoculture containers were probably contaminated during handling.

The purpose of this report is to describe the results of a prospective study on pulmonary histoplasmosis in French Guiana. Chest radiographs were performed in 232 French legionnaires returning from a two-year assignment in French Guiana. Further examinations were performed in a total of 8 subjects in whom chest radiographs demonstrated the presence of nodules in the lungs. No evidence of cancer or tuberculosis was found. Findings confirmed histoplasmomas in two cases and demonstrated probable histoplasmosis nodules in 6 cases including three involving calcified lesions. Five of these eight patients had been in high-risk rain forest environments. Pulmonary histoplasmosis should be considered as a possible diagnosis in subjects returning from endemic zones. Confirmation depends on a spectrum of findings. Calcified nodules require only radiographic surveillance with follow-up at six months. Non-calcified nodules require further investigation including CT-scan, bronchoscopy, and serological tests. Surgical biopsy may be necessary to achieve exact histological and mycological identification of the lesion and is recommended in smokers.

This report describes the results of epidemiological surveillance of cutaneous leishmaniasis in French military personnel in French Guiana. Data was collected regarding microscopic diagnosis, clinical manifestations, and lesion location as well as compliance with vector control measures. Year-to-year variations in the incidence in the general population have been attributed to changes in climatic conditions. Monitoring incidence and density curves, correlation of findings with local epidemiological data, and analysis of the most recent epidemic in 1998/99 (326 cases, attack rate 3.2% men years) highlight the importance of behavioral factors. The proportion of total cases involving military personnel varied widely from 20 to 85%. Investigation consistently showed that failure to apply elementary protective measures against sandfly bites was the most determinant factor in this proportion. Strict compliance with these measures appears to reduce the risk of infection considerably.

Objective: The aim of this study, conducted in the French Military hospitals, was to monitor the course of the antimicrobial sensibility of bacteria isolated from nosocomial infection in intensive care units., Patients and Methods: A prospective study has been conducted from January to December 1998 in all the intensive care units of the French Army. All the non-repetitive strains isolated from nosocomial infection were collected and sent to a reference centre. Antimicrobial susceptibility was determined by the agar dilution method. Beta-lactamase were identified by iso-electro-focalisation. Antibiotics choice and interpretative criteria were those of the "Comité Français de l'Antibiogramme de la Société Française de Microbiologie"., Results: A total of 849 strains are included in this study. Pseudomonas aeruginosa was the most frequently isolated bacterium (20%) followed by Escherichia coli (19%) Staphylococcus aureus (15%), coagulase-negative Staphylococci (CoNS) (11%) and Enterococci (7%). Imipenem was the most effective antibiotic against enterobacteriaceae (336 isolates; 100% susceptibility). Gentamicin (92%), amikacin (92%) third generation cephalosporins (83%), aztreonam (83%) and ciprofloxacin (78%) were also very effective. Resistance to III generation cephalosporins was correlated with an extended spectrum beta-lactamase (BLSE) in 36% of cases. This BLSE could be associated with an over production of the constitutive cephalosporinase. The most frequent species producing BLSE were Enterobacter aerogenes (75% of BLSE) and Klebsiella pneumoniae (17%). Among the 172 P. aeruginosa isolated, antimicrobial susceptibility were respectively: 71% for imipenem, 62%: tobramycin, 60%: amikacin 59%: ciprofloxacin 59% piperacillin + tazobactam, 55% piperacillin, 53%: ceftazidime and 44% for ticarcillin. Seventy per cent of the 96 CoNS and 50.2% of the 126 S. aureus isolated were resistant to methicillin. A strain of S. aureus and 2 CoNS strains had intermediate resistance to teicoplanin. Twenty per cent of the 59 Enterococci strains isolated were resistant to aminopenicillins (10/11 strains of E. faecium), and 9% presented a high level of resistance to gentamicine. One strain of E. faecium was resistant to vancomycin., Conclusion: The evolution of the susceptibility to antibiotics in intensive care units reflects the antibiotic pressure and level of cross-transmission. High rates of meticillin-resistance among staphylococci, of resistance to beta-lactams antibiotics among P. aeruginosa and of ciprofloxacin among Enterobacteriaceae are shown in this study. The implementation of appropriate strategies for surveillance and prevention is necessary.

The increasing hospital-to-hospital transmission of multiple drug-resistant bacteria is a major concern for bacteriology laboratories involved in nosocomial infection control. The interlaboratory reproducibility of pulsed-field gel electrophoresis (PFGE) for Pseudomonas aeruginosa typing was evaluated by asking four hospital laboratories (two in Lyon, one in Brest, and one in Marseille) to study 11 P. aeruginosa isolates, some of which were epidemiologically related, and the reference strain ATCC 27853. Two laboratories used the Genepath system, one the Chef DR II, system, and one the Chef Mapper system, Bio-Rad, restriction/Spe I. Profiles were read visually and by computerized comparison of restriction band molecular weights (Taxotron, software, PAD Grimont, Pasteur Institute, Paris, France). These two methods led to similar epidemiological conclusions. However, centralization of the data showed poor center-to-center reproducibility due to inadequate standardization of the procedure.

The lack of expensive equipment and well-trained laboratory technicians in developing countries makes it difficult to use standard methods (2 EIA confirmed by western blotting) to diagnose HIV infection. This led the WHO to develop simplified algorithms based on sequential screening tests, with no confirmation by immunoblotting. These algorithms were tested in the normal diagnosis conditions of a medical unit in Maputo, Mozambique. We tested 402 sera, collected with the consent of the patients concerned. The sera were first tested for HIV according to French regulations (2 EIA with western blot if at least one EIA was positive). This strategy identified 53 sera as positive for HIV1 and 1 serum as positive for HIV2. We then tested who algorithms, one for a predicted rate of prevalence < 10% and the other for a predicted rate of prevalence > 10%. Neither algorithm performed adequately for diagnostic purposes. Further evaluation with a panel of local sera is required to select the most suitable algorithm in terms of specificity and sensitivity, and algorithms should be throughly tested before inclusion in national AIDS control strategies.

Since the first outbreak in 1970, cholera epidemics have occurred regularly in Guinea. Until 1994, epidemics recurred every 8 years and were confined to the capital and coastal areas. The first cases in every epidemic were observed in coastal lagoons near the Sierra Leone border. In 1994, the disease demonstrated its migratory ability as the first cases were reported in towns located in far eastern inland areas. Spread of the disease from war-torn Sierra Leone and Liberia where epidemics have also been reported cannot be ruled out. Control measures have gradually been implemented to deal with these outbreaks and a treatment facility was built at the University of Conakry in 1994. Bacteriological studies including antibiotic susceptibility tests carried out at this center showed that the offending bacteria was Vibrio cholerae El Tor of the Ogawa group. Although this strain is relatively sensitive to all antibiotics, analysis of epidemiological data revealed high mortality rates at the beginning of every outbreak probably due to delays in organizing appropriate care. A major effort is now being made to improve the response time particularly in remote inland areas.

The far-infrared spectrum of nitryl chloride was studied using high-resolution Fourier-transform spectroscopy in the 300-525 cm-1 region. Vibrational band centers of fundamental, hot, and difference bands were determined. Furthermore, rotational and centrifugal distortion constants up to fourth order for the nu3 bands of 35ClNO2 and 37ClNO2 (centered at 370 and 364 cm-1, respectively) were obtained. The nu5 fundamental of ClNO2 (predicted around 410 cm-1) is very weak and overlapped by difference bands. Copyright 1998 Academic Press.

Major progress has been made in the epidemiology and prophylaxis of hepatitis A virus (HAV) since it was first discovered in stool samples by MacCallum in 1973. Seven types of the virus have been described. Types 1, 2, 3 and 7 occur in humans and types 4, 5 and 6 in monkeys, but genotype is not correlated with antigenic response. Immunization with the HM175 viral strain or natural infection by any of the virus types gives protection against all types of HAV affecting humans. Serological tests detect all types of the virus and make it possible to carry out epidemiological studies anywhere in the world. HAV is common in very young children in developing countries. Most ten-year-old children are immune and have no clinical signs of the illness. HAV infection has become less common in developed countries due to improvements in hygiene. Less than 40% of people under the age of 30 have been immunized. Non-immune individuals have a high risk of developing clinical hepatitis if they become infected and the older the patient at the time of infection, the more severe the disease is likely to be. The introduction of HAV into groups in which the majority of individuals have not been immunized may result in major local outbreaks. Prophylaxis schemes are developed on the basis of epidemiology. Vaccination is not routinely recommended in developing countries, except for visitors to those countries. Vaccination is recommended for individuals in high-risk groups, such as health workers, cooks, sewer maintenance engineers and tourists, in developed countries. In countries with an intermediate level of risk (East Europe, the Middle East and Southeast Asia), there is a high level of HAV infection and a low level of immunization. Vaccination programs are likely to be of value in these countries.

Management of blood eosinophilia in travelers returning from the tropics is controversial. In this prospective study, 102 asymptomatic tropical travelers underwent investigation and treatment for hypereosinophilia. In contrast with direct tests for parasitic infection which were positive in only 15% of cases, immunological tests were suggestive of helminthic infection is 77%. The most common diagnoses were toxocarosis (49%), strongyloidiasis (30%), and filariasis (19%). Anti-parasite treatment was undertaken based on laboratory findings (12 cases) or on presumptive diagnosis using two-agent therapy (ivermectin and praziquantel) in 13 cases or three-agent therapy (ivermectin, praziquantel, flubendazole) in 77 cases. As a result of treatment, eosinophil count returned to normal in 61% of cases and decreased in 30%. These findings suggest that presumptive treatment of blood eosinophilia can be undertaken in tropical travelers using three anti-parasitic drugs: ivermectin (1 x 0.4 mg/kg), flubendazole (2 x 100 mg per day for 3 days), and praziquantel (1 x 40 mg). As a precaution before using ivermectin, tests should be performed to detect loiasis which can lead to adverse reactions.

When two cholera epidemics broke out in Djibouti, respectively in 1993 and 1994, Bioforce was obliged to intervene. The first time, three goals were pursued: setting up a rehydration centre in a tent, organizing epidemiological surveillance and training local personnel in treatment and diagnosis techniques. The next year, the epidemic followed serious flooding. The epidemiological analysis showed that cholera had become endemic in the poor neighbourhoods of the town and that epidemic break-outs were favoured by contaminated surface water and disturbances in the distribution of drinking water. The epidemic of 1997, likewise following flooding, only confirmed this point of view.