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Resume Contexte et objectifs A la demande de la Direction generale de la sante, la Haute Autorite de sante (HAS), en partenariat avec la Societe de toxicologie clinique (STC) et avec la collaboration de la Societe francaise de medecine du travail (SFMT), la Societe francaise de sante publique (SFSP), la Societe francaise de toxicologie analytique (SFTA) et la Societe francophone de sante-environnement (SFSE) a elabore des recommandations pour le depistage des surexpositions environnementales a l’arsenic inorganique (Asi) et la prise en charge des populations concernees. Methode La methode d’elaboration utilisee est celle des Recommandations pour la pratique clinique (RPC) de la HAS (HAS, 2010). Resultats Les recommandations elaborees identifient : les sites susceptibles d’entrainer des surexpositions environnementales, a partir de la concentration d’Asi dans leur sol ; la fraction des residents qui constitue la population cible du depistage ; les modalites de ce depistage qui utilise le dosage de l’Asi et de ses metabolites dans les urines. En fonction des resultats du primo-depistage, elles precisent les indications et le deroulement de la surveillance biometrologique. Elles indiquent la fraction de la population exposee qui constitue la cible de la recherche de complications de la surexposition environnementale a l’Asi. Elles precisent les modalites de cette recherche. Enfin, elles proposent des mesures pour le traitement et la prevention des contaminations par l’Asi de l’environnement.

International audience; French Guiana is a European ultraperipheric region located on the northern Atlantic coast of South America. It constitutes an important forested region for biological conservation in the Neotropics. Although very sparsely populated, with its inhabitants mainly concentrated on the Atlantic coastal strip and along the two main rivers, it is marked by the presence and development of old and new epidemic disease outbreaks, both research and health priorities. In this review paper, we synthetize 15 years of multidisciplinary and integrative research at the interface between wildlife, ecosystem modification, human activities and sociodemographic development, and human health. This study reveals a complex epidemiological landscape marked by important transitional changes, facilitated by increased interconnections between wildlife, land-use change and human occupation and activity, human and trade transportation, demography with substantial immigration, and identified vector and parasite pharmacological resistance. Among other French Guianese characteristics, we demonstrate herein the existence of more complex multi-host disease life cycles than previously described for several disease systems in Central and South America, which clearly indicates that today the greater promiscuity between wildlife and humans due to demographic and economic pressures may offer novel settings for microbes and their hosts to circulate and spread. French Guiana is a microcosm that crystallizes all the current global environmental, demographic and socioeconomic change conditions, which may favor the development of ancient and future infectious diseases.

Although the development of vaccines for the prevention of arboviral diseases has been a priority in recent years, prevention strategies continue to depend on vector control. Risk maps at scales appropriate for these strategies can provide valuable information to assess entomological risk levels and guide actions. We used a spatio-temporal modeling approach to predict, at the local scale, the risk of homes potentially harboring Aedes aegypti larvae. The model used integrated larvae risk data collected in the field from September 2011 to February 2013, environmental data obtained from very high spatial resolution Pleiades imagery, and daily meteorological data, collected in the city of Matoury in French Guiana. Various environmental and meteorological conditions were identified as risk or protective factors for the presence of immature stages of Aedes aegypti in homes on a given date and used to produce dynamic maps with high spatial and temporal resolution. Aedes vector risk was modeled between 50 and 200 m, around houses, on a time scale of 3 to 5 days. The resulting model was extrapolated to other municipalities with the same characteristics of urbanization during the 2019-2020 dengue epidemic in French Guiana. This work represents a major opportunity to monitor the evolution of vector risk and constitutes information that could be particularly useful for public health authorities in charge of vector control.

Resume Introduction La Societe de toxicologie clinique (STC) a ete sollicitee par les pouvoirs publics pour produire des recommandations concernant la prise en charge des femmes enceintes exposees au mercure organique et leurs enfants a naitre. Methode Ces recommandations, avec la participation d’experts appartenant a des societes savantes concernees par la prise en charge des femmes enceintes et/ou de leurs enfants, ont ete etablies selon la methodologie des recommandations pour la pratique clinique definie par la Haute Autorite de sante (HAS). Resultats La principale source d’exposition de la population au methylmercure (MeHg) est alimentaire, notamment par la consommation de poissons fortement contamines. Les biomarqueurs d’exposition fiables pour la surveillance de l’impregnation au MeHg des populations sont le mercure total dans les cheveux et dans le sang total. L’effet critique du MeHg est l’alteration des fonctions cognitives resultant d’une exposition prenatale, et 11 μg/g de cheveux la valeur de la concentration capillaire de mercure maternelle, a partir de laquelle cet effet critique peut survenir chez l’enfant. La population prioritaire pour le depistage est celle des femmes en âge de procreer, ainsi que les enfants âges de moins de 7 ans, consommant plus de 2 portions de poissons par semaine, ou residant dans les bourgs isoles de Guyane, particulierement les femmes enceintes et leurs enfants allaites. Un suivi medical est recommande pour les femmes enceintes ayant une concentration capillaire de mercure superieure a 2,5 μg/g de cheveux (limite superieure de l’intervalle de confiance du 95e percentile dans la population francaise) ainsi que pour leurs nouveau-nes. Si la concentration capillaire chez la mere et/ou l’enfant a depasse 11 μg/g, l’enfant doit beneficier d’un suivi neurodeveloppemental. Conclusion Les mesures de reduction alimentaire des expositions sont primordiales : l’indication de la chelation se discute dans les cas ou des effets neurotoxiques severes sont possibles. Dans ces recommandations, la prise en charge d’une exposition maternelle au MeHg ainsi que celle de l’enfant a naitre sont detaillees dans un organigramme.

International audience; Background - Residents living close to agricultural lands might be exposed to pesticides through non-occupational pathways including spray drift and volatilization of pesticides beyond the treated area. Objective - This review aimed to identify and analyze scientific literature measuring pesticide exposure in non-farmworker residents living close to agricultural lands, and to suggest practical implications and needs for future studies. Methods - A review was performed using inclusion criteria to identify original articles of interest published between 2003 and 2018. Results - From the 29 articles selected in this review, 2 belonged to the same study and were grouped, resulting in a total of 27 studies. Seven studies assessed exposure to pesticides using environmental samples, 13 collected biological samples and 7 analyzed both. Nine studies included a reference group of residents living far from agricultural lands while 11 assessed the influence of the spraying season or spray events on pesticide exposures. Studies included in this review provide evidence that residents living near to agricultural lands are exposed to higher levels of pesticides than residents living further away. Discussion and conclusion - This review highlights that the following study design characteristics may be more appropriate than others to measure pesticide spray drift exposure in non-farmworker residents living close to agricultural lands: inclusion of a non-agricultural control group, collection of both biological and environmental samples with repeated sampling, measurements at different periods of the year, selection of numerous study sites related to one specific crop group, and measurements of pesticides which are specific to agricultural use. However, few studies to date incorporate all these characteristics. Additional studies are needed to comprehensively measure non-occupational pesticide exposures in this population in order to evaluate health risks, and to develop appropriate prevention strategies.

This assessment was conducted by a multidisciplinary task force of experts, “Emergency Collective Expertise Group—Impact of the COVID-19 pandemic and lockdown on dengue surveillance and vector control interventions” of the French Agency for Food, Environmental and Occupational Health & Safety (ANSES).; International audience; The concurrent circulation of dengue and coronavirus disease 2019 (COVID-19) may produce many unfavourable outcomes-such as co-infections; delays in diagnosis, treatment, and mitigation measures; overwhelming of the healthcare system; underreporting of cases; deterioration in surveillance and control interventions; and exacerbation of social inequalities. Indeed, lockdown is greatly compromising the effectiveness of vector control, especially social mobilization campaigns and preventive insecticide spraying in private spaces (indoor and peridomestic spraying). Thus, failure to appropriately implement the full range of vector control interventions can lead to a reduction in their overall effectiveness and an increasing risk of vector-borne diseases circulating. Consequently, the health community and policy makers should develop proactive policies and allocate adequate resources to prevent and manage the resurgence of dengue and other vector-borne diseases in the new era of COVID-19.

ObjectivesLarge amounts of mineral dust are transported from their African sources in the Saharan-Sahel region to the Caribbean Sea, generating peak exposures to particulate matter ≤10 µm (PM10). This study aimed to investigate the impact of Saharan dust episodes on preterm births in the Guadeloupe archipelago.MethodsThe study population consisted of 909 pregnant women who were enrolled in the TIMOUN mother-child cohort between 2004 and 2007. Desert dust episodes were assessed from PM10 concentrations recorded at the unique background air quality monitoring station located in Pointe-à-Pitre. For each woman, the daily PM10 concentrations were averaged over the entire pregnancy, and the proportion of days with intense dust episodes (≥55 µg PM10/m3) during pregnancy was calculated. Weighted logistic regression models adjusting for known individual sociomedical risk factors were used to estimate ORs and 95% CIs for preterm birth.ResultsDuring pregnancy, the mean PM10 concentrations ranged from 13.17 to 34.92 µg/m3, whereas the proportion of intense dust events ranged from 0.00% to 19.41%. Increased adjusted ORs were found for both the mean PM10 concentrations and the proportion of intense dust events (OR 1.40, 95% CI 1.08 to 1.81, and OR 1.54, 95% CI 1.21 to 1.98 per SD change, respectively). Restriction to spontaneous preterm births produced similar ORs but with wider 95% CIs.ConclusionConsidering the personal and social burden of this adverse pregnancy outcome, this finding is of importance for both healthcare workers and policy makers to provide necessary preventive measures.

International audience; Hair incorporates chemical compounds from the bloodstream and external sources as it grows. Different analytical procedures are proposed, but no consensus can be found for external contamination removal (washing stage). Thus, a major limitation of the use of hair analysis for human biomonitoring is the issue related to the washing efficiency, and the objective of this study was to propose a simple washing method for a better cleaning of external contamination. Based on a sequence of three steps of detergent or acid washing (Triton, nitric acid, and hydrochloric acid), the TNCl method was tested on raw and spiked samples and compared to other methods. Thirty-seven inorganic elements were analyzed by inductively Coupled Plasma Mass Spectrometry (ICP-MS) after washing and acid digestion of 10 hair samples (Li, Be, Na, Mg, Al, P, K, Ca, V, Cr, Fe, Mn, Co, N, Cu, Zn, As, Se, Sr, Mo, Ru, Ag, Cd, Sn, Sb, Cs, Ba, La, Ce, Nd, Gd, Lu, Tl, Pb, Bi, Th, and U). The inorganic element concentrations in the hair samples were compared to those reported in the literature. The TNCl method was shown to be more efficient than other methods based on the use of surfactants and organic solvents.

Epidemiologic studies are crucial to the estimation of numbers of deaths attributable to air pollution. In this paper, the authors present a framework for distinguishing estimates of attributable cases based on time-series studies from those based on cohort studies, the latter being 5-10 times larger. The authors distinguish four categories of death associated with air pollution: A) air pollution increases both the risk of underlying diseases leading to frailty and the short term risk of death among the frail; B) air pollution increases the risk of chronic diseases leading to frailty but is unrelated to timing of death; C) air pollution is unrelated to risk of chronic diseases but short term exposure increases mortality among persons who are frail; and D) neither underlying chronic disease nor the event of death is related to air pollution exposure. Time-series approaches capture deaths from categories A and C, whereas cohort studies assess cases from categories A, B, and C. In addition, years of life lost can only be derived from cohort studies, where time to death is the outcome, while in time-series studies, death is a once-only event (no dimension in time). The authors conclude that time-series analyses underestimate cases of death attributable to air pollution and that assessment of the impact of air pollution on mortality should be based on cohort studies.

International audience; Human behaviors are increasingly recognized to play a key role in the spread of infectious diseases. Although a set of social and cognitive determinants has been consistently found to affect the adoption of health protective behaviors aiming to control and prevent a variety of infections, little is currently known about the ecological drivers of these behaviors in epidemic settings. In this article, we took advantage of the outbreak of chikungunya, a reemerging mosquito-borne disease, that occurred in French Guiana in 2014-15 to test empirically the assumption proposed by Zielinski-Gutierrez and Hayden that the proximity of the disease and perceptions of the natural environment may considerably shape public response to an emerging health threat. To achieve this, a cross-sectional survey was conducted among high school students of the region ( = 1462) at an early stage of the epidemic. Surprisingly, spatial analysis of the collected data leads to counterintuitive results as the participants who lived in the most affected area expressed less concern about the disease and practiced preventive behaviors less frequently than did other participants. These paradoxical results may be attributed to the possible activation of risk denial processes which have previously been observed in the risk perception literature, and described by several social and psychological defensiveness theories.

International audience; BACKGROUND: Dengue fever is the most important arboviral infection that affects humans, particularly in tropical and subtropical regions. Here, we provide the first comprehensive overview of the severity of dengue epidemics in French Guiana. METHODOLOGY/PRINCIPAL FINDINGS: We monitored hospitalized cases between 2008 and 2013. Detailed clinical features and biological parameters were collected on a daily basis from all cases. Among the 1,356 cases, 216 (16%) were classified according to the WHO 2009 classification as dengue without warning signs (WS), 926 (68%) were classified as dengue with WS and 214 (16%) were classified as severe dengue. The severity rates were similar between the three major epidemics that occurred during the study period, whereas the hospitalization rate was highest in 2013. Fluid accumulation, aspartate aminotransferase (ASAT) counts>193 IU/L and platelet counts

Background During the last decade, French Guiana has been affected by major dengue fever outbreaks. Although this arbovirus has been a focus of many awareness campaigns, very little information is available about beliefs, attitudes and behaviors regarding vector-borne diseases among the population of French Guiana. During the first outbreak of the chikungunya virus, a quantitative survey was conducted among high school students to study experiences, practices and perceptions related to mosquito-borne diseases and to identify socio-demographic, cognitive and environmental factors that could be associated with the engagement in protective behaviors. Methodology/Principal Findings A cross-sectional survey was administered in May 2014, with a total of 1462 students interviewed. Classrooms were randomly selected using a two-stage selection procedure with cluster samples. A multiple correspondence analysis (MCA) associated with a hierarchical cluster analysis and with an ordinal logistic regression was performed. Chikungunya was less understood and perceived as a more dreadful disease than dengue fever. The analysis identified three groups of individual protection levels against mosquito-borne diseases: “low” (30%), “moderate” (42%) and “high” (28%)”. Protective health behaviors were found to be performed more frequently among students who were female, had a parent with a higher educational status, lived in an individual house, and had a better understanding of the disease. Conclusions/Significance This study allowed us to estimate the level of protective practices against vector-borne diseases among students after the emergence of a new arbovirus. These results revealed that the adoption of protective behaviors is a multi-factorial process that depends on both sociocultural and cognitive factors. These findings may help public health authorities to strengthen communication and outreach strategies, thereby increasing the adoption of protective health behaviors, particularly in high-risk populations., Author Summary Although dengue fever has been a focus of many awareness campaigns in Latin America, very little information is available about beliefs, attitudes and behaviors regarding vector-borne diseases among the population of French Guiana. At the initial onset of the first chikungunya outbreak, a quantitative survey was conducted among 1462 high school students aiming to study experiences, practices and perceptions related to mosquito-borne diseases and to identify factors that could be associated with protective behaviors. Chikungunya was less understood and perceived as a more dreadful disease than dengue fever. Students were clustered in three different groups according to their level of protection: “low” (30%), “moderate” (42%) and “high” (28%). Protective health behaviors were found to be performed more frequently among students who were female, lived with a parent who had a higher educational status, lived in an individual house, and had a better understanding of the disease. The results revealed that the adoption of protective behaviors is a multi-factorial process that depends on both socio-economic and cognitive factors. These findings may help the public health authorities to strengthen their communication and outreach strategy, thereby increasing the adoption of protective health behaviors, particularly in endemic countries and high-risk populations.

Background Dengue fever epidemic dynamics are driven by complex interactions between hosts, vectors and viruses. Associations between climate and dengue have been studied around the world, but the results have shown that the impact of the climate can vary widely from one study site to another. In French Guiana, climate-based models are not available to assist in developing an early warning system. This study aims to evaluate the potential of using oceanic and atmospheric conditions to help predict dengue fever outbreaks in French Guiana. Methodology/Principal Findings Lagged correlations and composite analyses were performed to identify the climatic conditions that characterized a typical epidemic year and to define the best indices for predicting dengue fever outbreaks during the period 1991–2013. A logistic regression was then performed to build a forecast model. We demonstrate that a model based on summer Equatorial Pacific Ocean sea surface temperatures and Azores High sea-level pressure had predictive value and was able to predict 80% of the outbreaks while incorrectly predicting only 15% of the non-epidemic years. Predictions for 2014–2015 were consistent with the observed non-epidemic conditions, and an outbreak in early 2016 was predicted. Conclusions/Significance These findings indicate that outbreak resurgence can be modeled using a simple combination of climate indicators. This might be useful for anticipating public health actions to mitigate the effects of major outbreaks, particularly in areas where resources are limited and medical infrastructures are generally insufficient., Author Summary Climatic determinants are amongst the most frequently cited in studies aimed at understanding and explaining the dynamics of vector-borne infections, and dengue in particular. French Guiana, a French overseas territory in which the vector Aedes aegypti is well established, experiences an epidemic cycle of dengue with large and prolonged epidemics occurring approximately every 3 years. Dengue is one of the most prioritized infectious diseases, and it requires an intense mobilization of local public health authorities, health services, and health professional and vector control services. A specific surveillance, preparedness and response plan has been developed based upon these needs. Gaining an accurate understanding of the drivers of dengue transmission is required to develop a model to predict the risk of an epidemic and to plan activities aimed at controlling it. Here, we assessed the effects of climatic factors on dengue spread to develop a predictive model of the epidemics in French Guiana on a country-wide scale. The goal of the model is to anticipate and plan both preventive and control activities. Given climate conditions, the model predicts that a dengue epidemic is likely to occur in early 2016. These conditions, which are favorable for Aedes mosquito proliferation, could also enhance the diffusion of other arboviruses, such as the Zika virus, in northeastern South America.

OBJECTIVE: To develop a criterion for early detection of bronchiolitis epidemics in Guadeloupe so that prevention and control strategies can be implemented in a more timely manner. METHODS: Weekly figures of bronchiolitis cases reported from July 2005-July 2010 by Guadeloupe's sentinel network were used. The criterion for detecting epidemics was created with data from the 2005-2009 bronchiolitis seasons. First, the baseline level for bronchiolitis (BL) was predicted by fitting a periodic regression on the non-epidemic observations; then a test was conducted of nine possible criteria to define epidemics by combining a statistical threshold set at different levels and a number of consecutive weeks with observations above and below them; lastly, the optimal criterion was selected considering its performances using expert advice as the gold standard. The selected criterion was validated with data from 2009-2010 season. RESULTS: The BL accounted for a linear trend and two sinusoidal functions of 52 and 26 weeks (R2 = 45%). According to the epidemic criterion selected, the statistical threshold was set at the upper limit of the one-sided 95% Confidence Interval of the predicted BL; 2 consecutive weeks with cases above it were necessary to set the start of an epidemic, and three again below to set the end. The median delay in launching the alerts was 2 weeks; there was one false alert; and the sensitivity, specificity, and positive predictive value for detecting epidemic weeks were 98%, 96%, 95%, respectively. During the validation period, the criterion launched one false alert and detected the epidemic with 4 weeks of delay. CONCLUSIONS: This criterion supports epidemiologists in timely interpretation of bronchiolitis epidemiological data for decision makers in Guadeloupe. In the future, it should be updated in accordance with trends in bronchiolitis epidemiology, and improved by integrating virological indicators. Its inclusion in an integrated management strategy for bronchiolitis prevention and control, supported by a bronchiolitis public health network, should also be encouraged.OBJETIVO: Formular un criterio para la detección temprana de las epidemias de bronquiolitis en Guadalupe, a fin de aplicar de manera más oportuna mejores estrategias de prevención y control. MÉTODOS: Se usaron las cifras semanales de los casos de bronquiolitis notificados desde julio del 2005 hasta julio del 2010 por la red de vigilancia de Guadalupe. El criterio para detectar las epidemias se estableció con los datos de las temporadas de bronquiolitis del 2005 al 2009. En primer lugar, se predijo el nivel basal de bronquiolitis ajustando una regresión periódica a los casos observados fuera de las epidemias; luego se pusieron a prueba nueve posibles criterios para definir las epidemias combinando un umbral estadístico establecido a diferentes niveles y un número de semanas consecutivas con las observaciones ubicadas por encima y por debajo de ellos; por último, se seleccionó el criterio óptimo conforme a su desempeño, usando el asesoramiento de expertos como criterio de referencia. El criterio seleccionado se validó con los datos de la temporada 2009-2010. RESULTADOS: El nivel basal de bronquiolitis presentaba una tendencia lineal y dos funciones sinusoidales de 52 y 26 semanas (R2 = 45%). Según el criterio de epidemia seleccionado, se fijó el umbral estadístico en el límite superior del intervalo de confianza de 95% unilateral del nivel basal de bronquiolitis previsto; para establecer el comienzo de una epidemia se requerían 2 semanas consecutivas con casos por encima de él, y 3 semanas con casos por debajo para determinar su finalización. La mediana del retraso para lanzar las alertas fue 2 semanas; hubo una alerta falsa; y la sensibilidad, la especificidad y el valor predictivo positivo para detectar las semanas de epidemia fueron 98%, 96% y 95%, respectivamente. Durante el período de validación se emitió, según el criterio, una alerta falsa y se detectó la epidemia con 4 semanas de retraso. CONCLUSIONES: Este criterio ayuda a los epidemiólogos a interpretar de manera oportuna los datos epidemiológicos de bronquiolitis a fin de tomar decisiones en Guadalupe. En el futuro, debe actualizarse según las tendencias en la epidemiología de la bronquiolitis, y mejorarse mediante su integración con indicadores virológicos. También debe promoverse su inclusión en una estrategia integrada de manejo para la prevención y el control de la bronquiolitis, apoyada por una red de salud pública relacionada con la bronquiolitis.

International audience; To strengthen active dengue surveillance in Saint Martin and Saint Barthélemy, two French Caribbean islands, we evaluated the epidemiological usefulness of collecting blood samples from NS1-positive dengue patients on filter paper to identify the dengue serotypes circulating in these regions during a 27-month period. This approach allowed dengue serotypes to be identified by reverse transcriptase-polymerase chain reaction in 90.1% of the total set of 666 samples analyzed and, in 95.5% of the samples collected during the acute phase of the disease. This prospective virological surveillance using blood samples absorbed onto filter paper, which were stored at 4°C and shipped at ambient temperature to a specialized laboratory for analysis, allowed us to avoid the logistic and financial costs associated with shipping frozen venous blood samples. This surveillance system offers a low-cost alternative for reinforcing dengue prevention in areas where specialized laboratories do not exist, notably by facilitating the early detection of potentially new dengue serotypes.

Introduction: Long-term exposure to air pollution (AP) has been shown to have an impact on mortality in numerous countries, but since 2005 no data exists for France. Objectives: We analyzed the association between long-term exposure to air pollution and mortality at the individual level in a large French cohort followed from 1989 to 2013. Methods: The study sample consisted of 20,327 adults working at the French national electricity and gas company EDF-GDF. Annual exposure to PM10, PM10–2.5, PM2.5, NO2, O3, SO2, and benzene was assessed for the place of residence of participants using a chemistry-transport model and taking residential history into account. Hazard ratios were estimated using a Cox proportional-hazards regression model, adjusted for selected individual and contextual risk factors. Hazard ratios were computed for an interquartile range (IQR) increase in air pollutant concentrations. Results: The cohort recorded 1967 non-accidental deaths. Long-term exposures to baseline PM2.5, PM10-25, NO2 and benzene were associated with an increase in non-accidental mortality (Hazard Ratio, HR = 1.09; 95% CI: 0.99, 1.20 per 5.9 μg/m3, PM10-25; HR = 1.09;95% CI: 1.04, 1.15 per 2.2 μg/m3, NO2: HR = 1.14; 95% CI: 0.99, 1.31 per 19.3 μg/m3 and benzene: HR = 1.10; 95% CI: 1.00, 1.22 per 1.7 μg/m3).The strongest association was found for PM10: HR = 1.14; 95% CI: 1.05, 1.25 per 7.8 μg/m3. PM10, PM10-25 and SO2 were associated with non-accidental mortality when using time varying exposure. No significant associations were observed between air pollution and cardiovascular and respiratory mortality. Conclusion: Long-term exposure to fine particles, nitrogen dioxide, sulfur dioxide and benzene is associated with an increased risk of non-accidental mortality in France. Our results strengthen existing evidence that outdoor air pollution is a significant environmental risk factor for mortality. Due to the limited sample size and the nature of our study (occupational), further investigations are needed in France with a larger representative population sample. Keywords: Air pollution, Mortality, Cohort study, Epidemiology, France

International audience; We performed a geographical analysis of cancer mortality in the communes surrounding an industrial mining complex (Salsigne, France) where suspicious levels of pollution due to arsenic were measured. Compared with that observed in a control area, we showed a significant excess of mortality due to all cancer types (ratio of standard mortality ratios (ratio of SMRs)=1.1), lung cancer (ratio of SMRs=1.8), pharynx cancer (ratio of SMRs=2.1) in the whole population, and due to digestive system cancer (ratio of SMRs=1.3) among women. The results were similar after controlling for the occupation distribution in the populations. Excluding mining complex workers deaths from the deaths in the studied populations did not modify the pattern of our results. We concluded that the excess of cancer deaths could not be exclusively due to potential professional exposures among the workers of the mining complex and are probably explained by environmental contamination.

Air pollution is associated with total mortality. This association may be confounded by uncontrolled time-varying risk factors such as influenza epidemics.We analyzed independent data on influenza epidemics from 7 European cities that also had data on mortality associated with particulates (PM10). We used 10 methods to control for epidemics (5 derived from influenza data and 5 from respiratory mortality series) and compared those results with analyses that did not control for these epidemics.Adjustment for influenza epidemics increased the PM10 effect estimate in most cases (% change in the pooled regression coefficient: -1.9 to 38.9 for total mortality and 1.3 to 25.5 for cardiovascular mortality). A 10-microg/m increase in PM10 concentrations (lag 0-1) was associated with a 0.48% (95% confidence interval=0.27-0.70%) increase in daily mortality unadjusted for influenza epidemics, whereas under the various methods to control for epidemics the increase ranged from 0.45% (0.26-0.69%) to 0.67% (0.46-0.89%). The corresponding figures for cardiovascular mortality were 0.85% (0.53-1.18%) with no adjustment and from 0.86% (0.53-1.19%) to 1.06% (0.74-1.39%) with the methods of control.The association between air pollution and mortality is not weakened by control for influenza epidemic irrespective of the method used. To adjust for influenza epidemics, one can use methods based on respiratory mortality counts instead of counts of influenza cases if the latter are not available. However, adjustment for influenza by any method tested did not markedly alter the air pollution effect estimate.

Background Leptospirosis is a neglected zoonosis affecting mainly tropical and subtropical regions worldwide, particularly South America and the Caribbean. As in many other countries, under-reporting of cases was suspected in the French West Indies because of inadequate access to diagnostic tests for the general population. Methodology/Principal findings In order to estimate the real incidence of leptospirosis in Guadeloupe and Martinique, a study was performed in 2011 using the three prevailing available biological tests for diagnosis: Microscopic Agglutination Test (MAT), IgM ELISA and PCR. The study investigated inpatients and outpatients and used active case ascertainment from data provided by a general practitioners’ sentinel network. The epidemiology of the disease was also described in terms of severity and demographic characteristics. Leptospirosis incidence was estimated at 69.4 (95%CI 47.6–91.1) and 60.6 (95%CI 36.3–85.0) annual cases per 100 000 inhabitants in Guadeloupe and Martinique, respectively, which was 3 and 4 times higher than previous estimations. Conclusion/Significance Inclusion of PCR and IgM ELISA tests for diagnosis of leptospirosis resulted in improved sensitivity in comparison with MAT alone. Our results highlighted the substantial health burden of the disease in these two territories and the importance of access to appropriate laboratory tests. Based on our results, PCR and IgM ELISA tests have now been included in the list of tests reimbursed by the national system of social security insurance in France. Our results also underline the relevance of implementing an integrated strategy for the surveillance, prevention and control of leptospirosis in the French West Indies., Author Summary Leptospirosis is a common disease in tropical regions around the world. It is caused by a bacteria excreted in environmental waters by mammals, especially rodents, through their urine. Leptospirosis has symptoms similar to other tropical diseases, including dengue fever, and early laboratory diagnosis is crucial to provide both appropriate treatments for patients and rapid control measures when an outbreak occurs. In 2011, we undertook a study to determine the incidence of leptospirosis in two territories (Guadeloupe and Martinique) in the French West Indies by establishing a surveillance network and implementing new diagnostic assays in order to ensure an exhaustive diagnostic analysis. We concluded that leptospirosis was previously significantly under-reported in the French West Indies and we recommended: 1- access to these new diagnostic tests for the entire population for a better detection of leptospirosis patients and, 2- the implementation of an integrated surveillance, alert and prevention system for the disease in this region. Our findings had raised the awareness of this neglected disease in the French West Indies and, as another consequence; new diagnostic tests are now reimbursed by the social security insurance in France.

International audience; Dengue is a public health concern across the globe, and an escalating problem in the Americas. As part of a wider programme (covering Latin America and South East Asia) to characterize the epidemiology of dengue in dengue endemic areas, we undertook a systematic literature review to assess epidemiological trends (incidence, timing and duration of outbreaks/epidemics, age and sex distribution, serotype distribution, seroprevalence and disease severity) for dengue across the French Territories of the Americas (FTA), in French Guiana, Guadeloupe, Martinique, Saint Martin and Saint Barthélemy between 2000 and 2012 (CRD42012002341: http://www.crd.york.ac.uk/prospero/display_record.asp?ID=CRD42012002341). Of 413 relevant data sources identified, 45 were eligible for inclusion. A large proportion of the available data were from national surveillance reports, and 12 publications were from peer-reviewed journals. During the review period, 3-5 epidemics were identified in each of the island territories and French Guiana, and epidemics were often associated with a shift in the predominant circulating dengue virus serotype. Substantial gaps in epidemiological knowledge were identified. In particular, information regarding dengue virus genotype distribution, seroprevalence and age distribution of dengue were lacking. Additionally, much of the available data were from epidemic years; data from inter-epidemic periods were sparse. Nevertheless, the available epidemiological data showed that dengue is endemic across the FTA and suggest an evolution towards hyperendemicity, highlighting the need to continue the efforts with the existing surveillance programmes to assist in planning an effective vaccination programme once a dengue vaccine is deployed.

Dengue is a public health concern across the globe, and an escalating problem in the Americas. As part of a wider programme (covering Latin America and South East Asia) to characterize the epidemiology of dengue in dengue endemic areas, we undertook a systematic literature review to assess epidemiological trends (incidence, timing and duration of outbreaks/epidemics, age and sex distribution, serotype distribution, seroprevalence and disease severity) for dengue across the French Territories of the Americas (FTA), in French Guiana, Guadeloupe, Martinique, Saint Martin and Saint Barthélemy between 2000 and 2012 (CRD42012002341: http://www.crd.york.ac.uk/prospero/display_record.asp?ID=CRD42012002341). Of 413 relevant data sources identified, 45 were eligible for inclusion. A large proportion of the available data were from national surveillance reports, and 12 publications were from peer-reviewed journals. During the review period, 3–5 epidemics were identified in each of the island territories and French Guiana, and epidemics were often associated with a shift in the predominant circulating dengue virus serotype. Substantial gaps in epidemiological knowledge were identified. In particular, information regarding dengue virus genotype distribution, seroprevalence and age distribution of dengue were lacking. Additionally, much of the available data were from epidemic years; data from inter-epidemic periods were sparse. Nevertheless, the available epidemiological data showed that dengue is endemic across the FTA and suggest an evolution towards hyperendemicity, highlighting the need to continue the efforts with the existing surveillance programmes to assist in planning an effective vaccination programme once a dengue vaccine is deployed. Protocol registration PROSPERO CRD42012002341, Author Summary Dengue disease is a mosquito-borne viral illness and is a major health concern in the Americas. We conducted a literature analysis and review to describe the epidemiology of dengue in the French Territories of the Americas (FTA), comprising French Guiana, Guadeloupe, Martinique, Saint Martin and Saint Barthélemy, to determine the impact of dengue on the population and to identify research priorities. We used well-defined methods to search for and identify relevant research conducted between 2000 and 2012. We identified an increase in the frequency, magnitude and severity of dengue epidemics across all the territories, an increase in the co-circulation of serotypes and the evolution to a hyperendemic state. Countries sharing geographical and environmental characteristics (e.g., Martinique and Guadeloupe, and Saint Barthélemy and Saint Martin) also shared characteristics in dengue epidemiology and its evolution, including timing of epidemics and circulating serotypes. Gaps in epidemiological knowledge provide several avenues for research, such as dengue virus genotype distribution, seroprevalence and age distribution of dengue cases. Epidemiological and virological surveillance of dengue in the FTA is evolving, and improved knowledge of the disease in these territories will improve anticipation of epidemics and aid implementation of control measures.

We applied sequential pattern extraction to identify the most important climatic factors related to dengue fever in French Guiana. Our findings suggest that the local climate has major effects on the occurrence of dengue epidemics in French Guiana and highlight the utility of the data mining approach to analyze disease surveillance data on a temporal and a spatial scale in relation to climatic, social and environmental variables. This study is a first step of a data mining project which will help to better understand and accurately predict temporal dynamics of dengue fever in French Guiana.

De nombreuses études épidémiologiques ont observé dans des contextes différents une faible relation à court terme entre les particules et la mortalité cardio-pulmonaire, même quand les normes de qualité de l'air n'étaient pas dépassées. La causalité de cette relation est un enjeu de santé publique en raison de l'importance de la population exposée. Notre objectif est de faire l'inventaire critique des arguments utilisés dans 15 revues de la littérature publiées. Nous expliquons l'importance de distinguer la validité de la causalité et analysons de façon systématique les différents critères de jugement dans le contexte des études écologiques temporelles. Notre conclusion est que la relation observée est valide et que la plupart des critères de causalité sont respectés. Diminuer le niveau d'exposition des populations aux particules est souhaitable. En Europe, en agissant à la source, notamment sur les émissions Diesel, on diminuera aussi d'autres polluants qui peuvent jouer un rôle sanitaire. Aux États-Unis, la situation est plus complexe car les particules sont surtout secondaires. Il est également indispensable de poursuivre les recherches pour mieux connaître les déterminants des expositions globales des individus et mieux comprendre le rôle toxique des différents facteurs physico-chimiques des particules.

A case-control study on respiratory cancers was conducted in New Caledonia (South Pacific), where a high incidence of malignant pleural mesothelioma had been observed. The disease pattern suggested an environmental exposure to asbestos. The first results showed that, in some areas, tremolite asbestos derived from local outcroppings was used as whitewash (locally named "pö"). All cases diagnosed between 1993 and 1995 (including 15 pleural mesotheliomas, 228 lung cancers, and 23 laryngeal cancers) and 305 controls were included in the study. Detailed information on past or present use of the whitewash, residential history, smoking, diet, and occupation was collected. The risk of mesothelioma was strongly associated with the use of the whitewash (odds ratio (OR) = 40.9; 95% confidence interval (CI): 5.15, 325). All Melanesian cases had been exposed. Among Melanesian women, exposure to the whitewash was associated with an increased risk of lung cancer (OR = 4.89; 95% CI: 1.13, 21.2), and smokers exposed to po had an approximately ninefold risk (OR = 9.26; 95% CI: 1.72, 49.7) compared with women who never smoked and had never used the whitewash. In contrast, no association was noted between exposure to pö and lung cancer risk among Melanesian men, probably because of lower exposure levels. Among non-Melanesians, the numbers of exposed subjects were too small to assess the effect of exposure to po. There was no indication of elevated risks for the other cancer sites.

Many countries now have epidemiological surveillance systems using health services-based indicators that allow detection of influenza epidemics. However, there is no accepted criterion for defining an influenza epidemic. An epidemic criterion has been developed, based on a time-series analysis of health services-based indicators collected on a weekly basis by a surveillance network implemented in the Paris region since 1984: the Groupe Regional d'Observation de la Grippe (GROG). For each new season, an epidemic threshold is independently defined for each health services-based indicator as the upper limit of the one-sided confidence interval of the expected value calculated from the weekly differences between the observed number of events and those predicted by a SARIMA model fitted on the non-epidemic data of previous seasons. Epidemic criteria for influenza A and B are then defined from the combination of both viral indicators and epidemic thresholds of individual health services-based indicators. Among health indicators, sick-leave data collected from GP's or the Health Insurance system, emergency home medical visits, and influenza-like-illness reported by GP's are the most sensitive indicators for the early recognition of epidemics. The exceeding of the above mentioned thresholds combined with virological data allows the specific detection of influenza A or B epidemics. This time-series method of analysing surveillance data provides early and reliable recognition of these epidemics.

This study examines short-term relationships between doctors' house calls and urban air pollution in Greater Paris for the period 1991–1995. Poisson regressions using nonparametric smoothing functions controlled for time trend, seasonal patterns, pollen counts, influenza epidemics, and weather. The relationship between asthma visits and air pollution was stronger for children. A relative risk (RRP95/P5) of 1.32 [95% confidence interval (CI) = 1.17–1.47)] was observed for an increase from the 5th to the 95th percentile (7–51 μg/m3) in daily concentrations of black smoke (BS). The risks for 24-hr sulfur dioxide and nitrogen dioxide levels were in the same range. Cardiovascular conditions, considered globally, showed weaker associations than angina pectoris/myocardial infarction, for which RRP95/P5was 1.63 (95% CI = 1.10–2.41) in relation to ozone ambient levels. Eye conditions were exclusively related to ozone (RRP95/P5= 1.17, 95% CI 1.02–1.33). Asthma visits and ozone showed an interaction with minimum temperature: an effect was observed only at 10°C or higher. In two-pollutant models including BS with, successively, SO2, NO2, and O3, only BS and O3effects remained stable. Along with mortality and hospital admissions, house call activity data, available on a regular basis, may be a sensitive indicator for monitoring health effects related to air pollution.

International audience; ObjectivesInfluenza seasonality remains poorly studied in Equatorial regions. Here we assessed the seasonal characteristics and environmental drivers of influenza epidemics in French Guiana, where influenza surveillance was established in 2006.MethodsSentinel GPs monitored weekly incidence of Influenza-like illnesses (ILI) from January 2006 through December 2010 and collected nasopharyngeal specimens from patients for virological confirmation. Times series analysis was used to investigate relationship between ILI and climatic parameters (rainfall and specific humidity).ResultsBased on 1533 viruses identified during the study period, we observed marked seasonality in the circulation of influenza virus in the pre-pandemic period, followed by year-round activity in the post-pandemic period, with a peak in the rainy season. ILI incidence showed seasonal autoregressive variation based on ARIMA analysis. Multivariate dynamic regression revealed that a 1 mm increase of rainfall resulted in an increase of 0.33% in ILI incidence one week later, adjusting for specific humidity (SH). Conversely, an increase of 1 g/kg of SH resulted in a decrease of 11% in ILI incidence 3 weeks later, adjusting for rainfall.ConclusionsIncreased rainfall and low levels of specific humidity favour influenza transmission in French Guiana.

International audience; OBJECTIVE: To describe the methodology used for implementing a surveillance system specifically for influenza A(H1N1)pdm09 in the French West Indies and French Guiana during an outbreak of this new virus in 2009-2010, and to report its main results. METHODS: This was an observational descriptive study of confirmed and probable cases of influenza A(H1N1)pdm09 hospitalized for at least 24 hours in 23 July 2009-3 March 2010. Reverse transcription polymerase chain reaction was performed on nasopharyngeal swab samples according to the Centers for Disease Control and Prevention protocol. A probable case was defined as fever > 38ºC or aches or asthenia with respiratory symptoms (cough or dyspnea). All confirmed and probable hospitalized cases were reported, along with patient's age, sex, clinical condition at admission, place and length of hospitalization, antiviral treatment, underlying conditions, complications, and clinical evolution. A case was classified as severe if respiratory assistance or intensive care was required or if death resulted. RESULTS: A total of 331 confirmed and 16 probable cases were hospitalized, with a hospitalization rate ranging from 4.3 per 1 000 clinical cases in Saint Martin to 10.3 in French Guiana. Of these, 36 were severe, and subsequently, 10 were fatal. The median length of stay was 4 days for non-severe cases and 9 days for severe (P < 0.05). The mean patient age was 21 years, and severe cases were significantly older than non-severe (mean: 38 years versus 19 years, P < 0.05). Underlying conditions associated with a higher risk of severity were 65 years of age or more (RR = 7.5, 95%CI = 4.2-13.3), diabetes (RR = 3.7, 95%CI = 1.5-9.4), cardiac insufficiency (RR = 8.4, 95%CI = 5.2-13.6), and morbid obesity (RR = 4.4, 95%CI = 1.8-10.4). Patients who received antiviral treatment within 2 days of symptom onset had shorter hospital stays (mean: 4 days versus 6.5 days, P < 0.05), and the illness tended to become less severe (11.1% versus 19.0%, P = 0.13). CONCLUSIONS: Active research of hospitalized cases enabled almost exhaustive surveillance. The pandemic's hospitalization rates and lethality were more moderate than expected. Some previously known underlying conditions of severity were confirmed during this outbreak. Furthermore, these results show the validity of early antiviral treatment.

We review 15 epidemiological studies published between September 1979 and March 1991 and assess the short-term impact of air pollution on health service-based morbidity indicators. Overall hospital activity indicators are more strongly associated with temperature than with pollution levels. A relationship between hospital respiratory admission indicators and acid-particulate pollution is observed at mean daily levels of 100–150 μg/m3/day for total suspended particulates (TSP) and < 100 μg/m3/day for sulphur dioxide. Hospital cardiovascular admission indicators are correlated to acid-particulate pollution and hospital psychiatric admission indicators appear to be linked to oxidant pollution. Findings on general medicine-based morbidity indicators are contrasted. Though the particulate pollution appears to have a significant impact on visits related to respiratory and cardiovascular conditions, temperature is seen to be the most important factor. On the other hand, such indicators seem to be more sensitive to low levels of air pollution than the hospital-based morbidity indicators. Most of the studies show a link between air pollution and health service-based morbidity indicators at a level of exposure below present standards. Such studies contribute to a better evaluation of the impact of air pollution on human health.

OBJECTIVE: To develop a criterion for early detection of bronchiolitis epidemics in Guadeloupe so that prevention and control strategies can be implemented in a more timely manner. METHODS: Weekly figures of bronchiolitis cases reported from July 2005-July 2010 by Guadeloupe's sentinel network were used. The criterion for detecting epidemics was created with data from the 2005-2009 bronchiolitis seasons. First, the baseline level for bronchiolitis (BL) was predicted by fitting a periodic regression on the non-epidemic observations; then a test was conducted of nine possible criteria to define epidemics by combining a statistical threshold set at different levels and a number of consecutive weeks with observations above and below them; lastly, the optimal criterion was selected considering its performances using expert advice as the gold standard. The selected criterion was validated with data from 2009-2010 season. RESULTS: The BL accounted for a linear trend and two sinusoidal functions of 52 and 26 weeks (R2 = 45%). According to the epidemic criterion selected, the statistical threshold was set at the upper limit of the one-sided 95% Confidence Interval of the predicted BL; 2 consecutive weeks with cases above it were necessary to set the start of an epidemic, and three again below to set the end. The median delay in launching the alerts was 2 weeks; there was one false alert; and the sensitivity, specificity, and positive predictive value for detecting epidemic weeks were 98%, 96%, 95%, respectively. During the validation period, the criterion launched one false alert and detected the epidemic with 4 weeks of delay. CONCLUSIONS: This criterion supports epidemiologists in timely interpretation of bronchiolitis epidemiological data for decision makers in Guadeloupe. In the future, it should be updated in accordance with trends in bronchiolitis epidemiology, and improved by integrating virological indicators. Its inclusion in an integrated management strategy for bronchiolitis prevention and control, supported by a bronchiolitis public health network, should also be encouraged.

Background During the last decades, dengue viruses have spread throughout the Americas region, with an increase in the number of severe forms of dengue. The surveillance system in Guadeloupe (French West Indies) is currently operational for the detection of early outbreaks of dengue. The goal of the study was to improve this surveillance system by assessing a modelling tool to predict the occurrence of dengue epidemics few months ahead and thus to help an efficient dengue control. Methods The Box-Jenkins approach allowed us to fit a Seasonal Autoregressive Integrated Moving Average (SARIMA) model of dengue incidence from 2000 to 2006 using clinical suspected cases. Then, this model was used for calculating dengue incidence for the year 2007 compared with observed data, using three different approaches: 1 year-ahead, 3 months-ahead and 1 month-ahead. Finally, we assessed the impact of meteorological variables (rainfall, temperature and relative humidity) on the prediction of dengue incidence and outbreaks, incorporating them in the model fitting the best. Results The 3 months-ahead approach was the most appropriate for an effective and operational public health response, and the most accurate (Root Mean Square Error, RMSE = 0.85). Relative humidity at lag-7 weeks, minimum temperature at lag-5 weeks and average temperature at lag-11 weeks were variables the most positively correlated to dengue incidence in Guadeloupe, meanwhile rainfall was not. The predictive power of SARIMA models was enhanced by the inclusion of climatic variables as external regressors to forecast the year 2007. Temperature significantly affected the model for better dengue incidence forecasting (p-value = 0.03 for minimum temperature lag-5, p-value = 0.02 for average temperature lag-11) but not humidity. Minimum temperature at lag-5 weeks was the best climatic variable for predicting dengue outbreaks (RMSE = 0.72). Conclusion Temperature improves dengue outbreaks forecasts better than humidity and rainfall. SARIMA models using climatic data as independent variables could be easily incorporated into an early (3 months-ahead) and reliably monitoring system of dengue outbreaks. This approach which is practicable for a surveillance system has public health implications in helping the prediction of dengue epidemic and therefore the timely appropriate and efficient implementation of prevention activities.

Many wild and domestic animals serve as reservoirs for pathogenic Leptospira strains and contaminate the environment by shedding the organisms in their urine. Humans are usually infected through abraded skin or mucous membrane contact with water contaminated by the urine of animal reservoirs, and less frequently by direct contact with animals or their urine. The mean incubation period is 10 days, with a usual range of 2–20 days. 1 Clinical manifestations are protean and the spectrum of symptoms range from subclinical or mild anicteric febrile illness to acute renal failure. Weil’s disease and respiratory distress syndrome are associated with high mortality. 1 Over the preceding decades, ecotourism and sporting events in tropical and sub-tropical areas have become more popular among travelers and athletes. These recreational activities in tropical areas have served to increase the risk of human exposure to these pathogens and consequently outbreaks of leptospirosis have been reported in these settings. 3, 4

Background: A dengue fever outbreak occurred in the interior of French Guiana from November 2005 onwards. An investigation, with epidemiological, entomological and public health inputs, was initiated. Its objectives were to confirm the outbreak, to describe the emergence of dengue fever in the High Maroni area and to initiate a specific public health response. Methods: The investigation was conducted in Maripasoula in February 2006, the biggest community in that part of the country. Definition criteria were used for suspected, probable and confirmed cases of dengue fever. An entomological evaluation for larvae and adult mosquitoes was carried out. Some personal and collective vector control measures were set up by the vector control team. Results: This survey identified 127 suspected dengue fever cases, whereas the epidemiological surveillance system detected only six probable and confirmed cases from the same place and for the same period. The proportion of dengue fever was higher in those people who had not travelled (23.5%) than within the population that had travelled (15.3%) in the three previous months ( P = 0.01). Larvae of Stegomyia aegypti were found throughout the town, and adults were captured in 90.9% of the houses. Conclusion: This is the first time that a dengue fever outbreak has been described beyond the coastal region of this French overseas Department.

SUMMARYIn April 2005, an outbreak of Chikungunya fever occurred on the island of Réunion in the Indian Ocean. During winter 2005, six patients developed meningoencephalitis and acute hepatitis due to Chikungunya virus. Our objectives were to determine the incidence and mortality of atypical Chikungunya viral infections and to identify risk factors for severe disease. A hospital-based surveillance system was established to collect data on atypical Chikungunya cases. Case reports, medical records and laboratory results were reviewed and analysed. We defined an atypical case as one in which a patient with laboratory-confirmed Chikungunya virus infection developed symptoms other than fever and arthralgia. We defined a severe atypical case as one which required maintenance of at least one vital function. We recorded 610 atypical cases of Chikungunya fever: 222 were severe cases, 65 affected patients died. Five hundred and forty-six cases had underlying medical conditions (of which 226 suffered from cardiovascular, 147 from neurological and 150 from respiratory disorders). Clinical features that had never been associated with Chikungunya fever were recorded, such as bullous dermatosis, pneumonia, and diabetes mellitus. Hypertension, and underlying respiratory or cardiological conditions were independent risk factors for disease severity. The overall mortality rate was 10·6% and it increased with age. This is the first time that severe cases and deaths due to Chikungunya fever have been documented. The information presented in this article may assist clinicians in identifying the disease, selecting the treatment strategy, and anticipating the course of illness.

The aim of the second phase of the Pollution Atmospherique et Affections Respiratoires Chroniques (PAARC) study, started in 1974, was to compare the long-term mortality between populations living in areas with different air pollution levels. In Bordeaux (France), four different areas were concerned by the study. The black smoke measures were realized between 1974 and 1981. After 1981, the stations set specifically for the study were not used any more. The purpose of this study was to estimate the evolution of air pollution in those areas between 1982 and 1997 using the measures of 12 Association de Prevention de la Pollution Atmospherique (APPA) stations located in Bordeaux city but not in the PAARC areas. The method used was divided in three phases: a correlation study between the stations of the different networks, a selection of the pertinent stations and the setting up of indicators using the arithmetic means method. Monthly means concentrations were estimated from January 1982 to December 1997. Models showed a decrease in black smoke levels whatever the area. The difference in level from one area to another, existing between the areas in 1974, was still with predicted values in 1997, but less important. Black smoke mean concentration for 1982-1997 was, respectively, 16.4 and 16.2 microg/m3, in areas 1 and 2. It was a little bit higher in area 3 with 18.9 microg/m3. Area 4 still has the highest level with 26.3 microg/m3. To conclude, this method enabled to assess different air pollution levels at different times in the four areas of the PAARC study in Bordeaux. Those levels could be used to study the impact of the air pollution on long-term mortality on populations living in the areas considered.

L'article 3 de la loi sur l'air et l'utilisation rationnelle de l'energie stipule que l'Etat assure la surveillance de la qualite de l'air et de ses effets sur la sante. Or, si les etudes epidemiologiques francaises menees jusqu'a present ont apporte des informations precieuses sur l'importance de l'impact sanitaire de la pollution atmospherique dans une zone geographique donnee, il n'est pas possible d'extrapoler leurs resultats a d'autres niveaux de pollution ou a d'autres situations caracterisees par des sources de pollution differentes, des facteurs environnementaux specifiques ou des populations differentes. Par ailleurs, realisees selon des protocoles de recueil ou d'analyse de donnees differents, elles rendent difficile la comparaison des resultats d'une ville a l'autre. Enfin, qu'il s'agisse de situations chroniques ou de pics de pollution, ces etudes n'ont pas permis d'estimer precisement la part contributive de chaque indicateur de pollution dans la survenue des effets sur la sante, ce qui, en termes decisionnels, limite leur portee. Depuis janvier 1997, avec l'appui du Ministere de l'Amenagement du Territoire et de l'Environnement et du Ministere charge de la Sante, le Reseau National de Sante Publique coordonne un programme multicentrique dans 9 villes (Bordeaux, Le Havre, Lille, Lyon, Marseille, Paris, Rouen, Strasbourg, Toulouse).Celui-ci vise a definir les modalites organisationnelles et techniques d'une surveillance epidemiologique dont le principe consiste a coupler les indicateurs de la surveillance metrologique de la qualite de l'air avec des indicateurs de sante recueillis en routine (mortalite, admissions hospitalieres). Dans chacune des villes, un comite technique est en charge de la mise en place de l’etude (elaboration du protocole d'etude, collecte, validation et exploitation des donnees, etc.). Il reunit les acteurs locaux et sa composition est variable selon les poles (professionnels de sante publique, reseau de surveillance de la qualite de l'air, epidemiologistes, cliniciens, etc.). Afin que les resultats de la surveillance epidemiologique puissent etre integres dans les processus d'evaluation et de decision au niveau local, le comite technique travaille en etroite relation avec un comite de pilotage. Celui-ci, place sous l'autorite du Prefet, est compose (en tout ou partie) du groupe « Air-Sante » du Plan Regional de la Qualite de l'Air. Les resultats de cette etude ainsi que les recommandations qui en decouleront seront disponibles fin 1998.

STUDY OBJECTIVE: To quantify the short term respiratory health effects of ambient air pollution in the Paris area. DESIGN: Time series analysis of daily pollution levels using Poisson regression. SETTING: Paris, 1987-92. MEASUREMENTS AND MAIN RESULTS: Air pollution was monitored by measurement of black smoke (BS) (15 monitoring stations), sulphur dioxide (SO2), nitrogen dioxide (NO2), particulate matter less than 13 microns in diameter (PM13), and ozone (O3) (4 stations). Daily mortality and general admissions to public hospitals due to respiratory causes were considered. The statistical analysis was based on a time series procedure using linear regression modelling followed by a Poisson regression. Meterological variables, epidemics of influenza A and B, and strikes of medical staff were included in the models. The mean daily concentration of PM13 and daily 1 hour maximum of SO2 significantly affected daily mortality from respiratory causes. An increase in the concentration of PM13 of 100 micrograms/m3 above its 5th centile value increased the risk of respiratory death by 17%. PM13 and BS were also associated with hospital admissions due to all respiratory diseases (4.1% increased risk when the BS level exceeded its 5th centile value by 100 micrograms/m3). SO2 levels consistently influenced hospital admissions for all respiratory diseases, chronic obstructive pulmonary disease, and asthma. Asthma was also correlated with NO2 levels. CONCLUSIONS: These results indicate that even though the relative risk is weak in areas with low levels of pollution, ambient air pollution, and especially particulate matter and SO2, nonetheless require attention because of the number of people exposed and the existence of high risk groups.

Dans les etudes epidemiologiques ecologiques temporelles, peu d'auteurs se sont interesses a la validation des indicateurs utilises pour estimer l'exposition de la population aux polluants atmospheriques. L'objectif de ce travail est de valider le recours a une moyenne arithmetique des moyennes quotidiennes de l'indice de fumees noires mesure par six postes de mesure comme indicateur de niveau de ce polluant en region parisienne. L'etude de la distribution des concentrations des polluants mesurees sur chaque poste, des structures temporelles des series par la methode de Box et Jenkins, et de leurs correlations nous ont permis de verifier l'homogeneite temporelle et geographique entre les postes de mesure. Celle etude est une premiere etape dans la demarche de validation de l'utilisation d'un indicateur d'exposition d'une population urbaine

The evaluation of the validity of the GROG's indicators is based on the first five years of activity, four of which being epidemic ones. A virological criterion for identifying epidemics is used as the gold standard. For each non-specific indicator, the ratio of epidemic weeks to non-epidemic weeks is outlined. Therefore we can define four epidemic situations in relation with the strains circulating and the non-specific indicators. Influenza A epidemics, which are known as a mortality problem can also be described according to its impact upon morbidity. As a result, it is possible to set up a sensitive and specific surveillance system for early detection of influenza epidemics. This objective is achieved by combining both the weekly collection of virological data as well as the collection of other available indicators either in routine practice or as provided by a network of sentinel practitioners. Such detection can pave the way for an improvement in preventive measures against the harmful effects on health of influenza epidemics.