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The heterogeneity in response to the H5N1 infection of three different species of waterfowl (Mute Swan, Common Pochard, Mallard), which were affected during the 2006 outbreak of highly pathogenic avian influenza in France, was suggested as the underlying reason for the small size of the outbreak. Through stochastic simulations of compartmental epidemiologic models that take into account both the individual behaviour of each of the three bird species and the interactions between them, the effect of host heterogeneity on the characteristics of the outbreak was analysed. Species diversity was found to induce either a decrease or an increase of the outbreak severity, depending on the mixing rates between the species and on the species to which the initially infected individual belonged to. It is found that an initially infected Mute Swan could generate major outbreaks, whereas Common Pochards and Mallards induce outbreaks of rather moderate sizes. [ABSTRACT FROM AUTHOR]

Wild birds share with humans the capacity for moving fast over large distances. During migratory movements, birds carry pathogens that can be transmitted between species at breeding, wintering, and stopover places where numerous birds of various species are concentrated. We consider the area of the Camargue (southern France) as an example to highlight how ad hoc information already available on birds' movements, abundance, and diversity can help assess the introduction and transmission risk for birdborne diseases in the western Mediterranean wetlands. Avian influenza and West Nile viruses are used as examples because birds are central to the epidemiology of these viruses. [ABSTRACT FROM AUTHOR]

Background: Millions of workers are exposed to polycyclic aromatic hydrocarbons (PAHs), a well-known family of carcinogens, but occupational exposure data about PAH mixture compositions are scarce.Objectives: To provide a detailed picture of airborne PAH exposures encountered in the French industrial landscape over the previous 20 years and to identify determinants driving exposures.Methods: Results from 1643 airborne samples of 16 gaseous and particulate PAHs implemented into the Exporisq HAP database from 1995 to 2014 were used to describe exposure levels and aerosol chemical composition in many industries and activities. Compliance of benzo[a]pyrene (BaP) levels with several existing occupational exposure limits for long-term exposure was assessed.Results: BaP levels were lower than those reported in the literature, but the level and composition of PAH mixtures were highly variable between and within industries. Numerous exposure determinants (e.g., product composition, type and temperature of process, ventilation and confinement) were assumed to explain these differences. The highest levels were found in industries using products derived from coal (aluminum, silicon, and coke production, manufacturing of carbon products and foundries), with mean BaP levels up to 23 times higher than the French recommended value of 150 ng/m3. Forty-seven percent of the occupational activities exceeded this value. Conversely, exposures resulting from petroleum-derived products were relatively low.Conclusions: As health effects depend on PAH levels but also on the composition of the mixture, exposure assessments must characterize the entire mixtures and record specific determinants to define homogeneous exposure groups and to accurately assess health risks. [ABSTRACT FROM AUTHOR]

Tularemia is a zoonosis caused by the bacterium Francisella tularensis Its specific diagnosis remains based on serological methods, while F. tularensis is rarely detected in clinical samples by culture or PCR. The aim of the present study was to evaluate the performance of the Serion enzyme-linked immunosorbent assay (ELISA) classic Francisella tularensis IgG and IgM tests (Virion/Serion GmbH Institute, Würzburg, Germany) and the VIRapid tularemia immunochromatographic test (ICT) (Vircell, Granada, Spain) compared to that of the in-house microagglutination test (MAT) and indirect immunofluorescence assay (IFA) currently used at the French National Reference Center for Francisella We evaluated 256 consecutive sera from 208 patients, including 51 confirmed and 23 probable tularemia cases, and 134 control patients not infected with F. tularensis The IFA tests displayed 72.5% sensitivity for IgM (cutoff titer ≥80) and 74.5% for IgG (cutoff titer ≥160), and 99.3% specificity for both IgM and IgG. Using cutoffs advocated by the manufacturer, the Serion ELISAs displayed 88.2% sensitivity for IgM and 86.3% for IgG antibodies; specificity was 94.8% for IgM and 95.5% for IgG. Compared to MAT and IFA tests, the Serion ELISAs allowed earlier detection of specific antibodies (1 to 2 weeks versus 2 to 3 weeks after the onset of symptoms). The ICT sensitivity and specificity were 90% and 83.6%, respectively, when considering the cutoff advocated by the manufacturer. In conclusion, the Serion ELISAs are useful as screening tests for tularemia diagnosis, but additional confirmatory tests (such as MAT and IFA) are needed, especially in areas of low endemicity., (Copyright © 2017 American Society for Microbiology.)

Background: Urban leptospirosis has increasingly been reported in both developing and developed countries. The control of the disease is limited because our understanding of basic aspects of the epidemiology, including the transmission routes of leptospires among rat populations, remains incomplete. Through the ability to distinguish among Leptospira strains in rats, multispacer sequence typing (MST) could provide a modern understanding of Leptospira epidemiology; however, to our knowledge, the distribution of Leptospira strains among urban rat colonies has not been investigated using MST., Aims and Methodology: The objective of this study was to identify the Leptospira strains present in rats (Rattus norvegicus) in Lyon (France) using MST and to characterize their spatial distribution. Kidneys and urine were collected from rats trapped live in seven locations in the city and in one suburban location. Each location was considered to represent a rat colony. Bacterial cultures and quantitative polymerase chain reaction (qPCR) assays were performed, and the L. interrogans DNA identified was then genotyped using MST. The distributions of Leptospira strains were spatially described., Key Results: Among 84 wild rats, MST profiles were obtained in 35 of 37 rats that had a positive result for L. interrogans by bacterial culture and/or qPCR analyses. All of the MST profiles were related to reference strains previously isolated from human patients that belong to the serogroup Icterohaemorrhagiae and the serovars [strain(s)] Copenhageni [Wijinberg or M20] (n = 26), Icterohaemorrhagiae [CHU Réunion] (n = 7), Icterohaemorrhagiae [R1] (n = 1) and Copenhageni [Shibaura 9] (n = 1). Each colony was infected with leptospires having the same MST profile., Major Conclusions: This study demonstrated that MST could be used for the purpose of field studies, either on culture isolates or on DNA extracted from kidneys and urine, to distinguish among L. interrogans isolates in rats. MST could thus be used to monitor their distributions in urban rats from the same city, thereby providing new knowledge that could be applied to explore the circulation of L. interrogans infection in rat colonies. Because the strains are related to those previously found in humans, this application of MST could aid in the source tracking of human leptospirosis, and the findings would be relevant for public health purposes according to the One Health principle.

A retrospective study was conducted to identify and describe the distribution pattern of Leptospira serogroups in domestic animals in France. The population consisted of cattle herds and dogs with clinically suspected leptospirosis that were tested at the "Laboratoire des Leptospires" between 2008 and 2011. The laboratory database was queried for records of cattle and dogs in which seroreactivity in Leptospira microagglutination tests was consistent with a recent or current infection, excluding vaccine serogroups in dogs. A total of 394 cattle herds and 232 dogs were diagnosed with clinical leptospirosis, and the results suggested infection by the Leptospira serogroup Australis in 43% and 63%, respectively; by the Leptospira serogroup Grippotyphosa in 17% and 9%, respectively; and by the Leptospira serogroup Sejroe in 33% and 6%, respectively. This inventory of infecting Leptospira serogroups revealed that current vaccines in France are not fully capable of preventing the clinical form of the disease., (© The American Society of Tropical Medicine and Hygiene.)

Introduction: Amyotrophic lateral sclerosis (ALS) is the most common motor neurone disease. It occurs in two forms: (1) familial cases, for which several genes have been identified and (2) sporadic cases, for which various hypotheses have been formulated. Notably, the β-N-methylamino-L-alanine (L-BMAA) toxin has been postulated to be involved in the occurrence of sporadic ALS. The objective of the French BMAALS programme is to study the putative link between L-BMAA and ALS., Methods and Analysis: The programme covers the period from 1 January 2003 to 31 December 2011. Using multiple sources of ascertainment, all the incident ALS cases diagnosed during this period in the area under study (10 counties spread over three French regions) were collected. First, the standardised incidence ratio will be calculated for each municipality under concern. Then, by applying spatial clustering techniques, overincidence and underincidence zones of ALS will be sought. A case-control study, in the subpopulation living in the identified areas, will gather information about patients' occupations, leisure activities and lifestyle habits in order to assess potential risk factors to which they are or have been exposed. Specimens of drinking water, food and biological material (brain tissue) will be examined to assess the presence of L-BMAA in the environment and tissues of ALS cases and controls., Ethics and Dissemination: The study has been reviewed and approved by the French ethical committee of the CPP SOOM IV (Comité de Protection des Personnes Sud-Ouest & Outre-Mer IV). The results will be published in peer-reviewed journals and presented at national and international conferences., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Host-feeding patterns play a key role in the transmission of vector-borne diseases such as West Nile fever, which involves two kinds of vertebrates, birds and mammals. In this study, we propose a theoretical formulation for mosquito host-feeding patterns using three quantities, as follows: the apparent attractiveness/contact probabilities, the conditional host(-feeding) preferences, and the enzootic versus bridge probabilities. Using results from host-baited trap collections, the quantities defined above were assessed for the most abundant mosquito species in the main West Nile virus focus of southern France. We found that host availability is important in determining the efficiency of bridge vectors, and that even ornithophilic mosquitoes like Culex species, classically classified as enzootic vectors, may turn out to be efficient bridge vectors in certain contexts of host abundance. Our developed theoretical framework can easily be adapted and applied to other experimental data and other vector-borne diseases.

Surveillance of work-related diseases and associated exposures is a major issue of public health, in particular for identifying and preventing new threats for health. In the occupational health context, the French national occupational disease surveillance and prevention network (RNV3P) have constructed a growing database that records every year all Occupational Health Problems (OHPs) diagnosed by a network of physician specialists. The network aims to provide and develop an expertise on the disease-exposure relationships, and uses the RNV3P database for developing the surveillance of OHPs and for the detection of emerging associations between diseases and occupational exposures. In this paper, we have developed the theoretical framework of the occupational exposome, defined as a network of OHPs linked by similar occupational exposures, as a novel approach which allows to characterize and to analyze the disease-exposure associations reported in the RNV3P database in the form of a relational network. Next, the occupational exposome is structured in terms of occupational exposure groups which constitute informative sub-sets of hazards considered as the backbone tree spectrum of the occupational exposures potentially related to a disease. To illustrate the wide possibilities of this method, the exposome approach is applied to the RNV3P database's sample of Non-Hodgkin Lymphomas (NHLs). As a result, we found that the NHL occupational exposome could be described in terms of 86 embedded exposure groups, defined as a set of OHPs sharing at least one component of the occupational multi-exposure. For example, "organic solvents and thinners" is the most represented hazards related to NHLs, but is also co-associated to "benzene", "ionizing radiations" or "agricultural products". From the knowledge stored in the database by physician experts, the occupational exposome constitutes a decisive step towards the evolving monitoring of multi-exposure associated to a given disease., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Objective: The French national occupational disease surveillance and prevention network (RNV3P) includes the 30 occupational disease consultation centres in university hospitals to which patients are referred for potentially work-related diseases, and an occupational health service. The aim of this work is to demonstrate the contribution of RNV3P to national health surveillance., Methods: Data from consultations are recorded in standardised occupational health reports and coded using international or national classifications. Programmed health surveillance is carried out through annual follow-up of annual referrals to experts for pre-selected disease-exposure associations, as well as incidence estimations for the well characterised working population followed by the occupational health service. Hypotheses on new emerging diseases are generated using statistical methods employed in pharmacosurveillance and by modelling as an exposome to analyse multiple exposures., Results: 58,777 occupational health reports were collected and analysed from 2001 to 2007. Referrals to the 30 university hospital centres increased significantly for asbestos-related diseases, mood disorders and adjustment disorders related to psychological and organisational demands, and for elbow and shoulder disorders related to manual handling. Referrals significantly decreased for asthma and for rhinitis related to exposure to organic dusts (vegetable or animal) or chemicals, except for cosmetics and cleaning products. Estimation of incidences by the occupational health services showed different patterns in different sectors of activity. The methods for detecting emerging diseases are presented and illustrated using the example of systemic sclerosis, identifying new exposures and new sectors of activity to be investigated., Conclusion: The RNV3P collects data from two complementary samples: 30 university hospital centres (workers or former workers) and an occupational health service (current workers). This dual approach is useful for surveillance and for hypothesis generation on new emerging disease-exposure associations.

To identify the mosquito species able to sustain the transmission of West Nile Virus (WNV) in the Camargue region (the main WNV focus of southern France), we assessed the vector competence of Culex modestus and Culex pipiens, the most abundant bird-feeders, and Aedes caspius, the most abundant mammophilic species occasionally found engorged with avian blood. Female mosquitoes were exposed to the infectious meal (10(10.3) plaque forming units (PFU)/mL) by membrane feeding, and hold at 26 degrees C. After the incubation period, disseminated infection was assessed by WNV detection using an indirect fluorescent antibody assay (IFA) on head squashes, and the transmission rate was assessed by the presence of WNV RNA in salivary secretions with a real-time reverse transcriptase-polymerase chain reaction (RT-PCR). After 14 incubation days, the disseminated infection and the transmission rates were 89.2% and 54.5% for Cx. modestus, 38.5% and 15.8% for Cx. pipiens, and 0.8% and 0 for Ae. caspius. Culex modestus was found to be an extremely efficient laboratory WNV vector and could thus be considered the main WNV vector in wetlands of the Camargue. Culex pipiens was a moderately efficient laboratory WNV vector, but in dry areas of the region it could play the main role in WNV transmission between birds and from birds to mammals. Aedes caspius was an inefficient vector of WNV in the laboratory, and despite its high densities, its role in WNV transmission may be minor in southern France.

The National Occupational Illness Surveillance and Prevention Network (RNV3P) established in 2002 as a network of experts from 29 university hospitals as well as occupational physicians records and monitors occupational health problems (OHPs) based on Soccupational health consultations in university hospitals in mainland France and in occupational medical health services (approximately 5000 OHPs/year for patients seen in hospital consultations). The OHP data are collected systematically according to a standardised code which is attributed based on main variables of interest: disease and co-morbidity (CIM-10), 1-5 impact codes (INRS), an occupational code (ILO) and a code for the type and domain of professional activity (NAF-93). For certain problems recorded, the clinician also reports a degree of imputance for attributing the level of certainty for the problem's relationship to the S main illness (weak, probable, strong). At present, 30,000 OHPs diagnosed and recorded in occupational illness consultation centers have been recorded in the information database and have been utilised for epidemiological surveillance. The surveillance activity of the network is carried out on two levels. First, a planned epidemiological health activity is programmed which focuses on estimating the incidence of illness--predefined problems. In a parallel fashion, research is developed to explore the tools which can be used to highlight emerging illness and develop methodologies to detect the relationships of unknown problems to the incidence of these illnesses--including those that present a communicable nature (either temporarily or over the long term), in certain professions or sectors.

Objective: To test data mining methods used in pharmacosurveillance in order to identify potential emerging disease-nuisance associations in the national occupational disease surveillance and prevention network (RNV3P) database., Methods: Proportional reporting ratios (PRR) used in pharmacosurveillance were applied to detect disproportional reporting of disease-nuisance associations which are not compensated by the national social security system., Results: The 24 785 reports of the RNV3P were grouped into 1344 different disease-nuisance associations reported more than twice, of which 422 did not give entitlement to compensation by the social security system. Among these associations, 162 were potentially emergent and generated a signal, of which eight associations involve cancer., Conclusion: This work is the first stage of an exploratory investigation submitting the questions raised to experts and involving participants in the network in reflection on the hypotheses generated.