Alan Ricardo Patlan Hernandez

Effects of pregnancy exposure to air pollution and surrounding residential greenness on childhood asthma, rhinitis, eczema, and their comorbidity : findings from the French mother-child cohort Pélagie: Cette thèse a étudié les associations de l’exposition à la pollution atmosphérique et les espaces verts pendant la grossesse avec la prévalence de l'asthme, de la rhinite, de l'eczéma et leur multimorbidité chez les enfants. Des données des suivis à 6 (n=1325) et à 12 ans (n=1119) de la cohorte bretonne mère-enfant Pélagie, ont été analysées. L'asthme, la rhinite, l'eczéma et un phénotype de multimorbidité ont été définis à l'aide de questionnaires validés. Les expositions pendant la grossesse ont été estimées à l'adresse résidentielle de chaque participant : les concentrations de PM2,5 et de NO2 à l'aide de modèles land use regression, et les espaces verts à l'aide de l'indice de végétation par différence normalisée (NDVI) dans un rayon de 300m. Des régressions logistiques ajustées, avec une stratification supplémentaire selon les zones urbaines et rurales, ont été réalisées. À 6 et 12 ans, la prévalence de l'asthme, de la rhinite, de l'eczéma et de la multimorbidité était respectivement d'environ 12 %, 23 %, 22 % et 11 %, et 60 % des mères vivaient en zones rurales pendant leur grossesse. Globalement, dans les analyses non stratifiées, nous n’avons pas observé des associations significatives entre le PM2,5 et de NO2 et les maladies d’intérêt. Cependant, des tendances pour l'asthme, l'eczéma et le phénotype de multimorbidité ont été observées. De même, le NDVI n'a pas montré d'associations significatives lors des deux suivis, à l'exception de l'eczéma et de la catégorie des enfants atteints d’une seule maladie à 6 ans, pour lesquels des associations protectrices ont été observées. Ces résultats soulignent la nécessité de recherches supplémentaires, en particulier au sein des populations rurales, afin de clarifier la relation de la pollution atmosphérique et les espaces verts pendant la grossesse, avec la santé respiratoire et les allergies chez l'enfant.

Freshwater sports expose practitioners to pathogens in the water environment and may result in infection. In French Brittany, these infections are particularly worrying, especially since 2016 with an increase in the incidence of leptospirosis reaching 1 case per 100,000 inhabitants, which represents the highest incidence observed since 1920. We aimed to estimate the prevalence of infectious diseases related to freshwater sports practice and to identify the factors associated with these infections among freshwater sports licensees in Brittany, France. From March 18, 2019, to May 8, 2019, we interviewed freshwater sports licensees (online study) and club presidents and instructors (phone study) in Brittany. Licensee participants were 18 years old or more and practiced at least one freshwater sport in one of the 79 Brittany clubs. We used logistic regression models to study the association between our variables of interest and potential risk factors. In total, 551 licensees (20.3% of the total number of licensees) and 38 clubs (48.1%) were surveyed. Among the licensees, 29 (5.3%) reported being diagnosed with leptospirosis, of which 12 (41.3%) occurred in the last 5 years. The most reported symptoms were skin irritation/itchy skin (24.3%) and 39 individuals (7.1%) reported at least one hospitalization in their lifetime for a disease related to freshwater sports. The occurrence of leptospirosis was negatively associated with boarding from a pontoon (odds ratio (OR)=0.20, 95% confidence interval (95% CI) 0.06–0.56), practicing for less than 4 years (OR=0.17, 95% CI 0.04–0.56) compared to more than 10 years, and the occurrence of leptospirosis was positively associated with taking a soapy shower after practice (OR=4.38, 95% CI 1.90–10.51). Eskimo roll was positively associated with the occurrence of otitis and conjunctivitis (OR=3.22, 95% CI 1.82–6.03), and skin irritation/itchy skin (OR=1.66, 95% CI 0.99–2.84). Otitis, conjunctivitis, and skin irritation/itchy skin are the most commonly reported freshwater sport-related diseases in French Brittany. Despite a good level of knowledge of prevention measures, their implementation by licensees and clubs remains low. Further studies are needed to identify practices associated with infectious risk in freshwater sports.

Undernutrition is more prevalent among children living in unsanitary environments with inadequate water, sanitation and hygiene (WASH). Despite good evidence for the effect of WASH on multiple infectious diseases, evidence for the effect of WASH interventions on childhood undernutrition is less well established, particularly for acute malnutrition. To assess the effectiveness of WASH interventions in preventing and treating acute childhood malnutrition, we performed electronic searches to identify relevant studies published between 1 January 2000 and 13 May 2019. We included studies assessing the effect of WASH on prevention and treatment of acute malnutrition in children under 5 years of age. Data were extracted by two independent reviewers. We included 26 articles of 599 identified references with a total of 43,083 participants. Twenty‐five studies reported on the effect of WASH on prevention, and two studies reported its effect on treatment of acute malnutrition. Current evidence does not show consistent associations of WASH conditions and interventions with prevention of acute malnutrition or with the improvement of its treatment outcomes. Only two high‐quality randomized controlled trials (RCTs) demonstrated that improved water quality during severe acute malnutrition treatment improved recovery outcomes but did not prevent relapse. Many of the interventions consisted of a package of WASH services, making impossible to attribute the effect to one specific component. This highlights the need for high‐quality, rigorous intervention studies assessing the effects of WASH interventions specifically designed to prevent acute malnutrition or improve its treatment.