Impact of the COVID-19 pandemic and lockdowns on emergency data related to mental health disorders in Nouvelle-Aquitaine, France.

This study estimates the association between emergency department (ED) visits for mental health disorders (MHDs) and the health context of the COVID-19 pandemic in the French region of Nouvelle-Aquitaine. This retrospective study took place between 2018 and 2021 using ED data. We defined the main exposure according to five periods: "Pre-pandemic (reference)", "First lockdown", "Second lockdown", "Third lockdown", and "Pandemic out-of-lockdown." We constructed the daily indicators for each MHD-related ED visit based on medical diagnoses. We described and then modeled the daily time series using generalized additive models with a quasi-Poisson regression. The analysis included 5,693,341 ED visits of which MHDs accounted for 4%. We observed a decline in ED use for most indicators, particularly during the first lockdown. Models revealed a statistically significant relative increase in ED visits for almost all MHDs during the first lockdown; for anxiety and child psychiatric disorders during the second lockdown; and only for child psychiatric disorders during the pandemic out-of-lockdown period. The public health crisis and lockdowns associated with the COVID-19 pandemic have been important sources of stress that could partially explain the deterioration of MHD indicators, thus leading to new public health concerns (notably among the youngest age group). Mental health is a major determinant of overall health and should therefore be considered in the management of crises that may require similar responses in the future.

Impact of non-pharmaceutical interventions, weather, vaccination, and variants on COVID-19 transmission across departments in France.

BACKGROUND: Multiple factors shape the temporal dynamics of the COVID-19 pandemic. Quantifying their relative contributions is key to guide future control strategies. Our objective was to disentangle the individual effects of non-pharmaceutical interventions (NPIs), weather, vaccination, and variants of concern (VOC) on local SARS-CoV-2 transmission. METHODS: We developed a log-linear model for the weekly reproduction number (R) of hospital admissions in 92 French metropolitan departments. We leveraged (i) the homogeneity in data collection and NPI definitions across departments, (ii) the spatial heterogeneity in the timing of NPIs, and (iii) an extensive observation period (14 months) covering different weather conditions, VOC proportions, and vaccine coverage levels. FINDINGS: Three lockdowns reduced R by 72.7% (95% CI 71.3-74.1), 70.4% (69.2-71.6) and 60.7% (56.4-64.5), respectively. Curfews implemented at 6/7 pm and 8/9 pm reduced R by 34.3% (27.9-40.2) and 18.9% (12.04-25.3), respectively. School closures reduced R by only 4.9% (2.0-7.8). We estimated that vaccination of the entire population would have reduced R by 71.7% (56.4-81.6), whereas the emergence of VOC (mainly Alpha during the study period) increased transmission by 44.6% (36.1-53.6) compared with the historical variant. Winter weather conditions (lower temperature and absolute humidity) increased R by 42.2% (37.3-47.3) compared to summer weather conditions. Additionally, we explored counterfactual scenarios (absence of VOC or vaccination) to assess their impact on hospital admissions. INTERPRETATION: Our study demonstrates the strong effectiveness of NPIs and vaccination and quantifies the role of weather while adjusting for other confounders. It highlights the importance of retrospective evaluation of interventions to inform future decision-making.

Progressive fibrosing interstitial lung disease: a clinical cohort (the PROGRESS study).

In patients with chronic fibrosing interstitial lung disease (ILD), a progressive fibrosing phenotype (PF-ILD) may develop, but information on the frequency and characteristics of this population outside clinical trials is lacking.We assessed the characteristics and outcomes of patients with PF-ILD other than idiopathic pulmonary fibrosis (IPF) in a real-world, single-centre clinical cohort. The files of all consecutive adult patients with fibrosing ILD (2010-2017) were examined retrospectively for pre-defined criteria of ≥10% fibrosis on high-resolution computed tomography and progressive disease during overlapping windows of 2 years. Baseline was defined as the date disease progression was identified. Patients receiving nintedanib or pirfenidone were censored from survival and progression analyses.In total, 1395 patients were screened; 617 had ILD other than IPF or combined pulmonary fibrosis and emphysema, and 168 had progressive fibrosing phenotypes. In 165 evaluable patients, median age was 61 years; 57% were female. Baseline mean forced vital capacity (FVC) was 74±22% predicted. Median duration of follow-up was 46.2 months. Annualised FVC decline during the first year was estimated at 136±328 mL using a linear mixed model. Overall survival was 83% at 3 years and 72% at 5 years. Using multivariate Cox regression analysis, mortality was significantly associated with relative FVC decline ≥10% in the previous 24 months (p<0.05), age ≥50 years (p<0.01) and diagnosis subgroup (p<0.01).In this cohort of patients with PF-ILD not receiving antifibrotic therapy, the disease followed a course characterised by continued decline in lung function, which predicted mortality.

Estimates of epidemiology, mortality and disease burden associated with progressive fibrosing interstitial lung disease in France (the PROGRESS study).

BACKGROUND: There is a paucity of data on the epidemiology, survival estimates and healthcare resource utilisation and associated costs of patients with progressive fibrosing interstitial lung disease (PF-ILD) in France. An algorithm for extracting claims data was developed to indirectly identify and describe patients with PF-ILD in the French national administrative healthcare database. METHODS: The French healthcare database, the Système National des Données de Santé (SNDS), includes data related to ambulatory care, hospitalisations and death for 98.8% of the population. In this study, algorithms based on age, diagnosis and healthcare consumption were created to identify adult patients with PF-ILD other than idiopathic pulmonary fibrosis between 2010 and 2017. Incidence, prevalence, survival estimates, clinical features and healthcare resource usage and costs were described among patients with PF-ILD. RESULTS: We identified a total of 14,413 patients with PF-ILD. Almost half of them (48.1%) were female and the mean (± standard deviation) age was 68.4 (± 15.0) years. Between 2010 and 2017, the estimated incidence of PF-ILD ranged from 4.0 to 4.7/100,000 person-years and the estimated prevalence from 6.6 to 19.4/100,000 persons. The main diagnostic categories represented were exposure-related ILD other than hypersensitivity pneumonitis (n = 3486; 24.2%), idiopathic interstitial pneumonia (n = 3113; 21.6%) and rheumatoid arthritis-associated ILD (n = 2521; 17.5%). Median overall survival using Kaplan-Meier estimation was 3.7 years from the start of progression. During the study, 95.2% of patients had ≥ 1 hospitalisation for respiratory care and 34.3% were hospitalised in an intensive care unit. The median (interquartile range) total specific cost per patient during the follow-up period was €25,613 (10,622-54,287) and the median annual cost per patient was €18,362 (6856-52,026), of which €11,784 (3003-42,097) was related to hospitalisations. Limitations included the retrospective design and identification of cases through an algorithm in the absence of chest high-resolution computed tomography scans and pulmonary function tests. CONCLUSIONS: This large, real-world, longitudinal study provides important insights into the characteristics, epidemiology and healthcare resource utilisation and costs associated with PF-ILD in France using a comprehensive and exhaustive database, and provides vital evidence that PF-ILD represents a high burden on both patients and healthcare services. Trial registration ClinicalTrials.gov, NCT03858842. ISRCTN, ISRCTN12345678. Registered 3 January 2019-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT03858842.

Q fever seroprevalence in parturient women: the EQRUN cross-sectional study on Reunion Island.

BACKGROUND: Q fever (Coxiella burnetii infection) has been associated with adverse perinatal outcomes. After investigating the obstetrical importance of Q fever on Reunion island and demonstrating an association between incident Q fever and miscarriage, we conducted a cross-sectional serosurvey to assess the prevalence of Coxiella burnetii infection among parturient women. METHODS: Between January 9 and July 24, 2014, within the level-4 maternity of Saint Pierre hospital and the level-1 maternity of Le Tampon, we proposed to screen all parturient women for Coxiella burnetii serology. Seropositivity was defined using indirect immunofluorescence for a dilution of phase 2 IgG titre ≥1:64. Further dilutions were chosen to discriminate recent or active infections from past or prevalent infections (< 1:128) and classify these as either possible (1:128), or probable (≥1:256). Recurrent miscarriage, stillbirth, preterm birth, small-for-gestational as well as a composite outcome of these adverse pregnancy outcomes were compared according to seropositivity using bivariate analysis or propensity score matching of seropositive and seronegative women on confounding factors. RESULTS: Among 1112 parturient women screened for Q fever over this 7-month period, 203 (18.3%) were seropositive. Overall weighted seroprevalence was of 20.1% (95%CI, 17.7-22.5%). Weighted seroprevalence of probable infections was 4.7% (95%CI 3.4-5.9%), while > 90% of positive serologies corresponded to past infections or false positives. Seropositivity was associated with none of the abovementioned adverse perinatal outcomes, whether in unpaired or matched analyses on propensity score. CONCLUSION: The magnitude and the pattern of seroprevalence suggest that Q fever is endemic on Reunion island. In this context, we found no significant contribution of prevalent Coxiella burnetii infection to adverse pregnancy outcomes. Although reassuring, these data put in our endemic context, with a previously demonstrated increased risk of incident Q fever associated miscarriage, encourage us to protect pregnant women against the risk of new infection, periconceptional or early in pregnancy.

Early assessment of the impact of mitigation measures to control COVID-19 in 22 French metropolitan areas, October to November 2020.

In France, measures including curfew and lockdown were implemented to control the COVID-19 pandemic second wave in 2020. This study descriptively assesses their possible effects, also relative to their timing. A considerable decrease in incidence of COVID-19 cases and hospital admissions was observed 7 to 10 days after mitigation measures were put in place, occurring earlier in metropolitan areas which had implemented these first. This temporal coincidence suggests the measures' positive impact, consistent with international experiences.

Pregnancy outcomes of Q fever: prospective follow-up study on Reunion island.

BACKGROUND: Q fever has been associated with perinatal complications. We conducted a prospective follow-up study to assess both the incidence of adverse pregnancy outcomes (APOs) associated with Coxiella burnetii infection and the contribution of Q fever to APOs. METHODS: Between May 1 and October 31, 2013, within the regional perinatal health care centre of Saint Pierre, Reunion island, we investigated unexplained miscarriages, stillbirths, preterm births or small-for-gestational age children. Seropositivity for C. burnetii antibodies was defined using indirect immunofluorescence for a phase 2 IgG titre ≥1:64. Acute Q fever was defined for a high phase 2 IgG titre ≥1:256 (compatible with recent or active infection) or the detection of C. burnetii genome in miscarriage products and placentas. Incidence rate ratios (IRR) for Q fever related APOs (taken as a composite outcome or individually) were assessed using Poisson regression models for dichotomous outcomes controlling major confounders. RESULTS: Over a 6-month period, 179 pregnant women suspected or diagnosed with an APO were investigated for Q fever, of whom 118 met the definition for an APO. Of these, 19 were seropositive and 10 presented a profile indicative of an acute infection. For three women with an acute Q fever, the chronology between the onset of infection, the APO (2 miscarriages, 1 preterm birth) and the seroconversion suggested causality in the pathogenesis. The cumulative incidence of Q fever related APOs was estimated between 2.2‰ and 5.2‰, whether causality was required or not. Both C. burnetii exposure and acute Q fever were independently associated with APOs (IRR 1.55, 95% CI 1.31-1.84; IRR 1.47, 95% CI 1.15-1.89, respectively). CONCLUSIONS: In the endemic context of Reunion island, acute Q fever may lead to APOs. To limit the burden of Q fever on reproduction, pregnant women should be kept away from farms and avoid direct contact with ruminants.

From the threat to the large outbreak: dengue on Reunion Island, 2015 to 2018.

BackgroundWith more than 300 million infections estimated annually worldwide, dengue is the most prevalent arboviral infection. On Reunion Island, after a large outbreak in 1977-78, only limited episodes of viral circulation or sporadic cases were reported till 2015.AimOur objective was to document and report on the circulation of dengue virus after the occurrence of a small outbreak during austral summer 2015/16 and until the large outbreak of 2018.MethodsBeside the mandatory notification of biologically confirmed dengue cases, additional systems of surveillance were set up: estimation of dengue-like syndrome in people seeking care by their family doctor, surveillance of emergency department visits related to dengue, surveillance of hospitalised dengue patients and deaths classifications.ResultsAfter a moderate outbreak during summer 2015/16 with 231 cases, 2017 was characterised by limited viral circulation (97 cases) which, however, persisted during the austral winter. By February 2018, the number of cases had increased and led to a peak at the beginning of May 2018. More than 6,000 cases were reported this year (dengue virus type 2 only). In addition, six deaths of dengue patients were notified.ConclusionIn 2017, the persistence of transmission during winter created favourable conditions for the emergence of an epidemic during summer 2018. After this moderate epidemic wave, the viral circulation persisted during winter 2018 for the second year, opening the door for the second wave in 2019 and for potential endemisation of the disease on Reunion Island in the near future.

Emergency department syndromic surveillance to investigate the health impact and factors associated with alcohol intoxication in Reunion Island.

In Reunion Island, alcohol is the most tried out psychoactive substance. To our knowledge, few indicators measuring the health burden of alcohol use exist on the island. In this context, an exploratory analysis based on syndromic surveillance data was implemented in order to describe the emergency department (ED) visits for alcohol intoxication (AI) and factors associated with their variations.An analysis of anonymized records routinely collected by the syndromic surveillance system was carried out. A daily indicator of ED visits for AI was built from a selection of ICD-10 codes between 2010 and 2012. Health impact of AI was first described comparing this indicator to all causes ED visits. Then, AI visits were analyzed with time-series methods using generalized additive Poisson regression models allowing for overdispersion. The following variables were included in the model: long-term trend, seasonality, day of the week, public and school holidays, days of festival and minimum social benefits payday.During the study period, 16 652 visits for AI were recorded in EDs of Reunion Island. AI visits were the second reason for ED visits (i.e. 4%) after traumatism. AI visits mainly concerned men (87%) and the age group of 25-54 years (69%). There was a significant increase in ED visits for AI during days of benefits payday, weekends and publics holidays.This study demonstrated the interest of syndromic surveillance to monitor non-infectious diseases. Time-series models showed a robust association between ED visits for AI and several factors.

A major impact of the influenza seasonal epidemic on intensive care units, Réunion, April to August 2016.

The 2016 seasonal influenza in Réunion in the southern hemisphere, was dominated by influenza A(H1N1)pdm09 (possibly genogroup 6B.1). An estimated 100,500 patients with acute respiratory infection (ARI) consulted a physician (cumulative attack rate 11.9%). Sixty-six laboratory-confirmed cases (65.7/100,000 ARI consultations) were hospitalised in an intensive care unit, the highest number since 2009. Impact on intensive care units was major. Correlation between severe cases was 0.83 between Réunion and France and good for 2009 to 2015.

Réunion Island prepared for possible Zika virus emergence, 2016.

Zika virus (ZIKV) has recently spread widely and turned into a major international public health threat. Réunion appears to offer conditions particularly favourable to its emergence and therefore prepared to face possible introduction of the virus. We designed a scaled surveillance and response system with specific objectives, methods and measures for various epidemiological phases including a potential epidemic. Several tools were developed in order to (i) detect individual cases (including a large information campaign on the disease and suspicion criteria), (ii) monitor an outbreak through several complementary systems allowing to monitor trends in disease occurrence and geographic spread and (iii) detect severe forms of the disease in collaboration with hospital clinicians. We put the emphasis on detecting the first cases in order to contain the spread of the virus as much as possible and try to avoid progress towards an epidemic. Our two main strengths are a powerful vector control team, and a close collaboration between clinicians, virologists, epidemiologists, entomologists and public health authorities. Our planned surveillance system could be relevant to Europe and island settings threatened by Zika virus all over the world.

Hospitalized cases of influenza A(H1N1)pdm09 in the French territories of the Americas, July 2009-March 2010.

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.

Epidemiology, Mortality and Healthcare Resource Utilization Associated With Systemic Sclerosis-Associated Interstitial Lung Disease in France.

Objectives: To investigate the clinical characteristics, epidemiology, survival estimates and healthcare resource utilization and associated costs in patients with systemic sclerosis-associated interstitial lung disease (SSc-ILD) in France. Methods: The French national administrative healthcare database, the Système National des Données de Santé (SNDS), includes data on 98.8% of the French population, including data relating to ambulatory care, hospitalizations and death. In our study, claims data from the SNDS were used to identify adult patients with SSc-ILD between 2010 and 2017. We collected data on clinical features, incidence, prevalence, survival estimates, healthcare resource use and costs. Results: In total, 3,333 patients with SSc-ILD were identified, 76% of whom were female. Patients had a mean age [standard deviation (SD)] of 60.6 (14.4) years and a mean (SD) individual study duration of 3.9 (2.7) years. In 2016, the estimated overall incidence and prevalence were 0.69/100,000 individuals and 5.70/100,000 individuals, respectively. The overall survival estimates of patients using Kaplan-Meier estimation were 93, 82, and 55% at 1, 3, and 8 years, respectively. During the study, 98.7% of patients had ≥1 hospitalization and 22.3% of patients were hospitalized in an intensive care unit. The total annual mean healthcare cost per patient with SSc-ILD was €25,753, of which €21,539 was related to hospitalizations. Conclusions: This large, real-world longitudinal study provides important insights into the epidemiology of SSc-ILD in France and shows that the disease is associated with high mortality, healthcare resource utilization and costs. SSc-ILD represents a high burden on both patients and healthcare services. Clinical Trial Registration:www.ClinicalTrials.gov, identifier: NCT03858842.

Preservative-free versus preserved glaucoma eye drops and occurrence of glaucoma surgery. A retrospective study based on the French national health insurance information system, 2008-2016.

PURPOSE: Preservatives contained in glaucoma eye drops have been shown to have a deleterious impact on the ocular surface. We aimed to assess the association between preservative exposure and the occurrence of further glaucoma surgery among patients with glaucoma or ocular hypertension in France. METHODS: The study concerned all patients who first received glaucoma eye drop treatments in a French medical-administrative database (EGB) between 2008 and 2015. Three groups were created according to the level of preservative exposure during the whole follow-up: '0% preservatives', 'mixed' and '100% preservatives'. The occurrence of glaucoma surgery was estimated according to preservative exposure indicators in Cox multivariate models adjusted on age, sex, number of glaucoma eye drops simultaneously used, systemic antihypertensive treatment and duration of treatment. RESULTS: The sample consisted of 12 454 patients. The median (interquartile range) follow-up was 4.1 (1.7-6.1) years. A total of 231 (1.9%) patients underwent glaucoma surgery during follow-up. On multivariable analysis, the risk of glaucoma surgery was increased for the 'mixed' group (hazard ratio [HR] = 3.94 [95% CI, 1.54-10.05]) and for the '100% preservative' group (HR = 7.97 [95% CI, 3.07-20.67]) when compared with the 0% preservative group. CONCLUSION: We found an association between exposure to glaucoma eye drop preservatives and the prevalence of further glaucoma surgery. While these data might be used to support the consideration of routine use of preservative-free drops, in the absence of a randomized clinical trial, they cannot prove a direct cause-and-effect relationship between preservative-free glaucoma eye drops and further glaucoma surgery.

Are the short-term effects of air pollution restricted to cardiorespiratory diseases?

Short-term effects of air pollution on common morbidity are largely unknown. The authors explored links between daily levels of air pollution (nitrogen dioxide, ozone, and particulate matter less than 10 microm in diameter (PM(10))) and medical home visits made for diverse reasons in Bordeaux, France, during 2000-2006. Daily numbers of visits were obtained from a network of general practitioners. The excess relative risk (ERR) of a visit for each indicator associated with increased pollutant levels was estimated by fitting a Poisson regression model, controlling for well-known confounding factors and temporal trends. Positive and significant associations were found between air pollution and most health indicators. A 10-microg/m(3) increase in PM(10) levels was associated with increases in visits for upper and lower respiratory diseases (ERRs were 1.5% (95% confidence interval (CI): 0.3, 2.7) and 2.5% (95% CI: 0.5, 4.4), respectively), headache and asthenia (ERR = 3.5%, 95% CI: 1.3, 5.9), and skin rash and conjunctivitis (ERR = 3.2%, 95% CI: -0.2, 6.8). Significant associations were also found between nitrogen dioxide and ozone and several health indicators. Distributed-lag models showed no harvesting effect, and some effects persisted up to 15 days after exposure increased. These results suggest that considering only the most severe effects of air pollution leads to underestimation of its impact on public health.

Seroprevalence of Coxiella burnetii (Q fever) Exposure in Humans on Reunion Island.

After the documentation of sporadic cases of Q fever endocarditis, we conducted a serosurvey to assess Coxiella burnetii exposure on Reunion Island. Two hundred forty-one stored frozen human sera were analyzed using an immunofluorescence assay. The weighted seroprevalence of Q fever was of 6.81% (95% confidence interval, 4.02%-9.59%). Despite the absence of infection in youths <20 years of age, exposure was not driven by age or by gender. There was a spatial disparity in exposure across the island, with higher prevalence being reported in regions where ruminant farms are present. The seroprevalence pattern suggests that Q fever is endemic on Reunion Island.

A major epidemic of chikungunya virus infection on Reunion Island, France, 2005-2006.

In January 2005, an epidemic of chikungunya fever broke out in the Comoro Islands and lasted until May 2005. In April, cases were also reported in Mayotte and Mauritius. On Réunion Island, the first cases were reported at the end of April. Surveillance of this epidemic required an adaptive system, which at first was based on active and retrospective case detection around the cases reported, then relied on a sentinel network when the incidence increased. Emerging and severe forms of infection were investigated. Death certificates were monitored. By April 2006, the surveillance estimate was 244,000 cases of chikungunya virus infection, including 123 severe cases and 41 of maternoneonatal transmission, with an overall attack rate of 35%. Chikungunya infection was mentioned on 203 death certificates and significant mortality was observed. This epidemic highlighted the need for a mutual strategy of providing information on arboviral diseases and their prevention and control between countries in the southwestern Indian Ocean.

Short term effects of air pollution on hospitalizations for cardiovascular diseases in eight French cities: the PSAS program.

INTRODUCTION: Short term associations between air pollution indicators and hospitalizations for cardiovascular diseases have been suggested by epidemiological and clinical studies. The present study aims at estimating the association between particles with diameter <10 microm (PM(10)), nitrogen dioxide (NO(2)) and ozone and hospitalizations for cardiovascular diseases in eight French cities during the 1998-2003 period. METHODS: The daily number of hospitalizations in each city was extracted from the French hospital information system (PMSI) for cardiovascular diseases, cardiac diseases, ischemic heart diseases and stroke. Excess relative risks (ERRs) of hospitalization associated with a 10 microg/m(3) increase in pollutant levels were estimated in each city by fitting a Poisson regression model, controlling for well-known confounding factors and temporal trends. City-specific results were then combined by inverse variance weighting. RESULTS: Daily number of hospitalizations for cardiovascular diseases was associated with PM(10) levels (for a 10 microg/m(3) increase, ERR=0.8%, 95% CI: [0.2, 1.5]), with NO(2) (1.1%, [0.6, 1.6]) but not with ozone (0.1% [-0.2%, 0.5%]). Associations were stronger in people aged 65 years and over, and when only hospitalizations for ischemic heart diseases were considered. No association was found between strokes and air pollution levels. DISCUSSION: Our study suggests that the ambient levels of air pollutants currently experienced in the eight French cities, which are close to European air quality guidelines, are yet linked to a short term increase of hospitalizations for cardiovascular diseases. These results are consistent with epidemiological and toxicological data on the cardiovascular effects of air pollution.

Serological Evidence of Contrasted Exposure to Arboviral Infections between Islands of the Union of Comoros (Indian Ocean).

A cross sectional serological survey of arboviral infections in humans was conducted on the three islands of the Union of Comoros, Indian Ocean, in order to test a previously suggested contrasted exposure of the three neighboring islands to arthropod-borne epidemics. Four hundred human sera were collected on Ngazidja (Grande Comore), Mwali (Mohéli) and Ndzouani (Anjouan), and were tested by ELISA for IgM and/or IgG antibodies to Dengue (DENV), Chikungunya (CHIKV), Rift Valley fever (RVFV), West Nile (WNV), Tick borne encephalitis (TBEV) and Yellow fever (YFV) viruses and for neutralizing antibodies to DENV serotypes 1-4. Very few sera were positive for IgM antibodies to the tested viruses indicating that the sero-survey was performed during an inter epidemic phase for the investigated arbovirus infections, except for RVF which showed evidence of recent infections on all three islands. IgG reactivity with at least one arbovirus was observed in almost 85% of tested sera, with seropositivity rates increasing with age, indicative of an intense and long lasting exposure of the Comorian population to arboviral risk. Interestingly, the positivity rates for IgG antibodies to DENV and CHIKV were significantly higher on Ngazidja, confirming the previously suggested prominent exposure of this island to these arboviruses, while serological traces of WNV infection were detected most frequently on Mwali suggesting some transmission specificities associated with this island only. The study provides the first evidence for circulation of RVFV in human populations from the Union of Comoros and further suggests that the virus is currently circulating on the three islands in an inconspicuous manner. This study supports contrasted exposure of the islands of the Comoros archipelago to arboviral infections. The observation is discussed in terms of ecological factors that may affect the abundance and distribution of vector populations on the three islands as well as concurring anthropogenic factors that may impact arbovirus transmission in this diverse island ecosystem.