Evolution climatique et canicule en milieu urbain : apport de la télédétection à l'anticipation et à la gestion de l'impact sanitaire

rapport finalSummer warming trends in Western Europe are increasing the incidence, intensity and duration of heat waves. These are especially deadly in cities owing to surface properties, anthropogenic heat and pollutants. In August 2003, for nine consecutive days, the Paris metropolitan area experienced an extreme heat wave that caused 4,867 heatrelated deaths. A time series of 84 satellite thermal images, from July 21 to August 21 2003 was used to analyze surface temperature variations and the associated heat stress. Satellite observations indicate significant surface temperature gradients and contrasted daytime / nighttime urban heat island patterns. The relatively small temperature amplitude in reference to a normal summer confirms the impact of high minimum temperatures on the heat wave process, lack of nighttime relief and on the subsequent heat stress and mortality. Maps of temperature thresholds and areas most vulnerable to heat stress were delineated. Thermal indices were produced at the addresses of 482 case studies and were integrated into a regression model to estimate the risk factors of mortality for elderly people during the heat wave. Thermal indices for minimum, maximum, mean surface temperatures and diurnal amplitude were tested on the day of death and 1, 2, 6 or 13 days preceding. Results from the linear regression analysis were statistically significant for minimum temperatures. For an increase of 0.5°C, the death risk can be twice as high. A summertime satellite surveillance is being developed to inform the public and authorities about extreme surface temperatures and related heat stress. This analysis demonstrates the relevance of satellite remote sensing in monitoring heat waves in megacities, in estimating the health impact and implementing alert systems and public health strategies

Conditions for the success and the feasibility of health mediation for healthcare use by underserved populations: a scoping review

OBJECTIVE: This article aims to analyse the conditions under which health mediation for healthcare use is successful and feasible for underserved populations. METHOD: We conducted a scoping review on the conditions for effective health mediation according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews standards. We searched for articles in the following databases: PubMed, PsychINFO, Scopus and Cairn published between 1 January 2015 and 18 December 2020. We selected the articles concerning health mediation interventions or similar, implemented in high-income countries and conducted among underserved populations, along with articles that questioned their effectiveness conditions. We created a two-dimensional analysis grid of the data collected: a descriptive dimension of the intervention and an analytical dimension of the conditions for the success and feasability of health mediation. RESULTS: 22 articles were selected and analysed. The scoping review underlines many health mediation characteristics that articulate education and healthcare system navigation actions, along with mobilisation, engagement, and collaboration of local actors among themselves and with the populations. The conditions for the success and the feasability were grouped in a conceptual framework of health mediation. CONCLUSION: The scoping review allows us to establish an initial framework for analysing the conditions for the success and the feasability of health mediation and to question the consistency of the health mediation approach regarding cross-cutting tensions and occasionally divergent logic

Int J Environ Res Public Health

Diet, screen time, physical activity, and sleep combine into lifestyle patterns with synergistic effects on health. This study aimed to identify lifestyle patterns in children without housing and assess their associations with physical and mental health and family socio-ecological factors. In the 2013 ENFAMS cross-sectional survey (children aged 6-12 experiencing homelessness, Greater Paris area, n = 235), parents reported socio-ecological factors, children's behaviours, and mental health (the latter was also child-reported). Nurses measured children's haemoglobin concentrations and body mass index. Principal component analysis was used to derive sex-specific lifestyle patterns. Hierarchical linear regressions and "outcome-wide" analyses assessed, respectively, these patterns' relations to health and family socio-ecological factors. A rather healthy lifestyle pattern-similarly characterized by diverse diet and high sleep time-was identified, with slight differences by sex. Scores for this pattern were higher for children in food-secure or higher-income households, whose parents were proficient in French, who slept longer, or who received more social support compared to their counterparts, with some nuances by sex. Higher scores for this pattern were associated with higher prosocial behaviour scores (girls) and lower anxiety and hyperactivity-inattention symptoms scores (boys), but not with physical health. For this underserved and understudied population, the results highlight the importance of family socio-ecological factors in shaping the lifestyles and mental health of children

The Impact of Heat Islands on Mortality in Paris during the August 2003 Heat Wave

Background: Heat waves have a drastic impact on urban populations, which could increase with climate change

Int J Environ Res Public Health

Scientific literature tends to support the idea that the pregnancy and health status of fetuses and newborns can be affected by maternal, parental, and contextual characteristics. In addition, a growing body of evidence reports that social determinants, measured at individual and/or aggregated level(s), play a crucial role in fetal and newborn health. Numerous studies have found social factors (including maternal age and education, marital status, pregnancy intention, and socioeconomic status) to be linked to poor birth outcomes. Several have also suggested that beyond individual and contextual social characteristics, living environment and conditions (or "neighborhood") emerge as important determinants in health inequalities, particularly for pregnant women. Using a comprehensive review, we present a conceptual framework based on the work of both the Commission on Social Determinants of Health and the World Health Organization (WHO), aimed at describing the various pathways through which social characteristics can affect both pregnancy and fetal health, with a focus on the structural social determinants (such as socioeconomic and political context) that influence social position, as well as on intermediary determinants. We also suggest that social position may influence more specific intermediary health determinants; individuals may, on the basis of their social position, experience differences in environmental exposure and vulnerability to health-compromising living conditions. Our model highlights the fact that adverse birth outcomes, which inevitably lead to health inequity, may, in turn, affect the individual social position. In order to address both the inequalities that begin in utero and the disparities observed at birth, it is important for interventions to target various unhealthy behaviors and psychosocial conditions in early pregnancy. Health policy must, then, support: (i) midwifery availability and accessibility and (ii) enhanced multidisciplinary support for deprived pregnant women

Mental health impact among hospital staff in the aftermath of the Nice 2016 terror attack: the ECHOS de Nice study

BACKGROUND: The Nice terror attack of July 14, 2016 resulted in 84 deaths and 434 injured, with many hospital staff exposed to the attack, either as bystanders on site at the time of the attack ('bystander exposure') who may or may not have provided care to attack victims subsequently, or as care providers to victims only ('professional exposure only'). The objective of this study is to describe the impact on mental health among hospital staff by category of exposure with a particular focus on those with 'professional exposure only', and to assess their use of psychological support resources. METHOD: An observational, cross-sectional, multicenter study conducted from 06/20/2017 to 10/31/2017 among all staff of two healthcare institutions in Nice, using a web questionnaire. Collected data included social, demographic and professional characteristics; trauma exposure category ('bystanders to the attack'; 'professional exposure only'; 'unexposed'); indicators of psychological impact (Hospital Anxiety and Depression Scale); PTSD (PCL-5) level; support sought. Responders could enter open comments in each section of the questionnaire, which were processed by inductive analysis. RESULTS: 804 staff members' questionnaires were analysed. Among responding staff, 488 were exposed (61%): 203 were 'bystanders to the attack', 285 had 'professional exposure only'. The staff with 'professional exposure only' reported anxiety (13.2%), depression (4.6%), suicidal thoughts (5.5%); rates of full PTSD was 9.4% and of partial PTSD, 17.7%. Multivariate analysis in the 'professional exposure only' category showed that the following characteristics were associated with full or partial PTSD: female gender (OR = 2.79; 95% CI = 1.19-6.56, p = 0.019); social isolation (OR = 3.80; 95% CI = 1.30-11.16, p = 0.015); having been confronted with an unfamiliar task (OR = 3.04; 95% CI = 1.18-7.85; p = 0.022). Lastly, 70.6% of the staff with 'professional exposure only' with full PTSD did not seek psychological support. CONCLUSION: Despite a significant impact on mental health, few staff with 'professional exposure only' sought psychological support. Robust prevention and follow-up programs must be developed for hospital staff, in order to manage the health hazards they face when exposed to exceptional health-related events such as mass terror attacks. STUDY REGISTRATION: Ethical approval for the trial was obtained from the National Ethics Committee for Human Research (RCBID N° 2017-A00812-51)

Front Public Health

BACKGROUND: Sheltered homeless families suffer from deleterious living conditions such as housing instability (i.e., moving from one shelter to another) that could be an additional barrier to healthcare utilization. Few studies have specifically examined perinatal health in homeless mothers and their utilization of prenatal healthcare. This study aimed to identify social determinants such as living conditions (i.e., housing instability) associated with inadequate prenatal care utilization (PCU) in sheltered homeless mothers in the Greater Paris area in France. METHODS: The homeless children and families cross-sectional survey [ENFAMS: (Enfants et familles sans logement)] was performed on a random representative sample of homeless families living in shelters in the greater Paris area in 2013. Following French guidelines, PCU was deemed inadequate if one or more of the following criteria was met: attending fewer than 50% of recommended prenatal visits, PCU initiation after the first trimester of pregnancy, and fewer than three ultrasounds during the entire pregnancy. Families were interviewed in 17 languages by trained peer interviewers in face-to-face interviews. Structural equation modeling was used to identify factors associated with inadequate PCU and to estimate correlations between them. RESULTS: This study analyzed data on 121 homeless sheltered mothers who had at least one child less than one year old. They were socially disadvantaged and most were born outside France. One in five (19.3%) had inadequate PCU. Associated factors were socio-demographic characteristics (young age, primiparous), health status (dissatisfaction with self-perceived general health), and living conditions (housing instability in the second and third trimesters). CONCLUSION: It is essential to reduce housing instability to help sheltered mothers to benefit from social, territorial and medical support and healthcare utilization. Housing stability for pregnant sheltered homeless mothers should be a priority to ensure better PCU and guarantee the newborn's health as much as possible

Heliyon

BACKGROUND: -A study to assess lead exposure of traveller children aged from 9 months to 18 years old was conducted in Charente-France between 2017 and 2019. METHODS: A face-to-face questionnaire was administered to each participating family (N = 78). Blood samples were collected, and in case of lead poisoning, an environmental survey of soil, dust and water samples was also performed. RESULTS: -Among the 100 children, they were 39 girls and 61 boys. Among them, 40 suffered from lead poisoning (Blood Lead Level ≥50 μg/L). Being a boy aged between 11 and 14 years old, and participating in lead exposure at-risk activities were significantly associated with higher mean blood lead level. CONCLUSION: -The high levels of lead detected advocate the reinforcement of lead poisoning screening for all children in the traveller population

Prenatal and postnatal exposure to persistent organic pollutants and Infant growth: A pooled analysis of seven european birth cohorts

Background: Infant exposure to persistent organic pollutants (POPs) may contribute to obesity. However, many studies so far have been small, focused on transplacental exposure, used an inappropriate measure to assess postnatal exposure through breastfeeding if any, or did not discern between prenatal and postnatal effects. Objectives: We investigated prenatal and postnatal exposure to POPs and infant growth (a predictor of obesity). Methods: We pooled data from seven European birth cohorts with biomarker concentrations of polychlorinated biphenyl 153 (PCB-153) (n = 2,487), and p,p´-dichlorodiphenyldichloroethylene (p,p´-DDE) (n = 1,864), estimating prenatal and postnatal POPs exposure using a validated pharmacokinetic model. Growth was change in weight-for-age z-score between birth and 24 months. Per compound, multilevel models were fitted with either POPs total exposure from conception to 24 months or prenatal or postnatal exposure. Results: We found a significant increase in growth associated with p,p´-DDE, seemingly due to prenatal exposure (per interquartile increase in exposure, adjusted β = 0.12; 95% CI: 0.03, 0.22). Due to heterogeneity across cohorts, this estimate cannot be considered precise, but does indicate that an association with infant growth is present on average. In contrast, a significant decrease in growth was associated with postnatal PCB-153 exposure (β = –0.10; 95% CI: –0.19, –0.01). Conclusion: To our knowledge, this is the largest study to date of POPs exposure and infant growth, and it contains state-of-the-art exposure modeling. Prenatal p,p´-DDE was associated with increased infant growth, and postnatal PCB-153 with decreased growth at European exposure levels

Modeling the influence of open water surfaces on the summertime temperature and thermal comfort in the city

Due to the combination of rapid global urbanization and climate change, urban climate issues are becoming relatively more important and are gaining interest. Compared to rural areas, the temperature in cities is higher (the urban heat island effect) due to the modifications in the surface radiation and energy balances. This study hypothesizes that the urban heat island can be mitigated by introducing open surface water in urban design. In order to test this, we use the WRF mesoscale meteorological model in which an idealized circular city is designed. Herein, the surface water cover, its size, spatial configuration, and temperature are varied. Model results indicate that the cooling effect of water bodies depends nonlinearly on the fractional water cover, size, and distribution of individual lakes within the city with respect to wind direction. Relatively large lakes show a high temperature effect close to their edges and in downwind areas. Several smaller lakes equally distributed within the urban area have a smaller temperature effect, but influence a larger area of the city. Evaporation from open water bodies may lower the temperature, but on the other hand also increases the humidity, which dampens the positive effect on thermal comfort. In addition, when the water is warmer than the air temperature (during autumn or night), the water body has an adverse effect on thermal comfort. In those cases, the water body eventually limits the cooling and thermal comfort in the surrounding city, and thus diverges from the original intention of the intervention