Éditeur(s) : HAL CCSD
Résumé : International audience
Studying the ecology of Leishmania parasites is essential for understanding and controlling the epidemiology of the diseases they cause. Despite their abundance and diversity in neotropical forests, few studies have been conducted to investigate the potential involvement of Chiroptera in the Leishmania pathogenic complexes. However, phlebotomine sand flies are known to colonize the same anthropized habitat, are attracted to bats, and are able to transmit trypanosomatids. Thus, 216 bats representing 29 species were sampled in the field in different primary and secondary forests of French Guiana where human cutaneous leishmaniases have been reported, together with 62 non-volant mammals. A series of 411 tissue samples representing 47 mammalian species were cultured and screened for the presence of Leishmania spp. by a genus-specific polymerase chain reaction. All 278 individuals surveyed were negative. Thus, bats do not appear to be involved in the Lishmania parasitic cycles in the Guyanas.
The American journal of tropical medicine and hygiene

halsde-00339305
https://hal.archives-ouvertes.fr/halsde-00339305

Éditeur(s) : HAL CCSD Elsevier Masson
Résumé : National audience
Les leishmanioses sont des maladies parasitaires à transmission vectorielle observées sur tous les continents, à l’exception de l’Amérique du Nord et de l’Australie. Nous focaliserons ici sur la leishmaniose viscérale méditerranéenne due à Leishmania infantum et dont l’incidence annuelle est estimée entre 1200 et 2000 cas. Son cycle biologique est zoonotique avec un réservoir animal essentiellement canin. Les récentes observations épidémiologiques sont rapportées ici, notamment la mise en évidence du portage humain asymptomatique et l’extension de la zone endémique de la leishmaniose canine. La prise en charge thérapeutique de la leishmaniose viscérale méditerranéenne du patient immunocompétent fait essentiellement appel à l’amphotéricine B liposomale. Le débat existe toujours sur la pertinence d’une prophylaxie secondaire ou des traitements itératifs à chaque rechute chez le patient co-infecté par le VIH. Summary Leishmaniasis are protozoan infections transmitted by the bite of the sandflies, widely reported except in North-America and Australia. Here, we focus on mediterranean visceral leishmaniasis due to Leishmania infantum, with an estimated annual incidence of 1200–2000 cases. Its biological cycle is zoonotic and mainly involves the canine reservoir. The recent epidemiological observations are reported here, particularly the asymptomatic carriage but also the extension of the canine enzooty. Regarding treatment of immunocompetent patients, the drug of choice for mediterranean visceral leishmaniasis is liposomal amphotericin B. In case of HIV-Leishmania co-infection, the interest of secondary prophylaxis is still in debate
ISSN: 2210-6545

hal-01225489
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01225489
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01225489/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01225489/file/Mise%20au%20point%20et%20actualit%C3%A9s%20sur%20la%20leishmaniose%20visc%C3%A9rale%20m%C3%A9diterran%C3%A9enne.pdf
DOI : 10.1016/j.antinf.2014.12.005

Éditeur(s) : HAL CCSD Elsevier Masson
Résumé : International audience
Invasive aspergillosis is a major cause of mortality in allogeneic bone marrow transplant recipients and patients treated for blood malignancies. The diagnostic tools, treatments and preventive strategies, essentially developed for neutropaenic patients, have not been assessed in populations whose immune systems are considered to be competent. Beside the standard picture of chronic Aspergillus infection, the incidence of invasive aspergillosis is increasing in non neutropaenic patients, such as those with chronic lung diseases or systemic disease treated with long-term immunosuppressive drugs and solid organ transplant recipients. This study reviews the specific features of invasive aspergillosis in non neutropaenic subjects (NNS) and discusses the value of the diagnostic tools and treatment in this population. A better understanding of the pathophysiology and the epidemiological characteristics of invasive aspergillosis would provide a means of adapting the staging and classification of the disease for NNS. Invasive aspergillosis is under diagnosed in NNS who may already be colonised when they receive immunosuppressive treatment; this can lead to an adverse outcome in patients who are considered to be a moderate risk population.
ISSN: 0761-8425

hal-01118185
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01118185
DOI : 10.1016/j.rmr.2010.01.004
PUBMED : 20965392

Éditeur(s) : Elsevier
Résumé : The Summer Syndrome is a new shrimp disease that has been affecting a shrimp growout farm in New Caledonia since end of 1997. It was recognized to be caused by a systemic vibriosis due to Vibrio nigripulchritudo. This new disease turned out almost immediately enzootic in the shrimp farm involved and has affected all its crops ever since. Since the year 2000, V. nigripulchritudo strains have been found in several shrimp farms, although Summer Syndrome is still limited to one particular area, affecting, since 2003, two adjoining farms. As part of a multidisciplinary research program, a high-frequency survey was carried out during the summer 2002-2003 in two shrimp farms: one affected farm and another one in which pathogenic strains could be isolated but without any disease event. It permitted a good description of V. nigripulchritudo dynamics in shrimp and the ecosystem in both farms. The study of virulence characteristics of some isolates showed that pathogenic and non-pathogenic strains occur in the shrimp farms environment and that both may be found at the same time in one farm. Our results strongly suggest a persistence of pathogenic strains in wet zones of the pond sediment at low concentrations between crops in the affected farm, and their development during the rearing cycle as a cause of shrimp infection.
Aquaculture (0044-8486) (Elsevier), 2006-03 , Vol. 253 , N. 1-4 , P. 105-113

Droits : 2005 Elsevier B.V. All rights reserved
http://archimer.ifremer.fr/doc/2006/publication-1110.pdf
DOI:10.1016/j.aquaculture.2005.07.031
http://archimer.ifremer.fr/doc/00000/1110/

Éditeur(s) : HAL CCSD Elsevier Masson
Résumé : International audience
Construction works in healthcare establishments produce airborne fungal spores and considerably increase the risk of exposure of immunosuppressed patients. It is necessary to reinforce protective measures, or even to implement specific precautions, during this critical phase. The aim of these precautions is to protect both those areas, which are susceptible to dust, and patients at risk of a fungal infection particularly invasive aspergillosis. When construction works are planned in healthcare establishments, the first step consists in the characterisation of the environmental fungal risk and the second one in proposing risk management methods. It is then essential to establish impact indicators in order to evaluate the risk management precautions applied. The working group promoted by the French societies of medical mycology and hospital hygiene (SFMM & SF2H) details here both environmental and epidemiological impact indicators that can be used.
ISSN: 1156-5233

hal-00759179
https://hal.archives-ouvertes.fr/hal-00759179
DOI : 10.1016/j.mycmed.2012.01.003
PUBMED : 23177816

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Ciguatera Fish Poisoning (CFP) is a non-bacterial seafood poisoning well characterized in the remote archipelagos of French Polynesia, yet poorly documented in the Society archipelago, most notably on Moorea, the second most populated island in French Polynesia, which counts a high proportion of fishermen fishing on a regular basis. To address this knowledge gap, a holistic study of the ciguatera issue was conducted on Moorea. First, ciguatera risk was analysed in terms of incidence rate, fish species most commonly involved and risk stratification in Moorea lagoon based on 2007–2013 epidemiological data. A mean incidence rate of 8 cases per 10,000 inhabitants for the study period and an average under-reporting rate of 54% were found. Taking into account hospitalization and medication fees, and loss of productive days, the health-related costs due to CFP were estimated to be USD $1613 and $749 for each reported and unreported case, respectively, with an overall cost of USD $241,847 for the study period. Comparison of the present status of CFP on Moorea with a risk map established in the late 1970’s showed that the spatial distribution of the risk has stayed relatively stable in time, with the north shore of the island remaining the most prone to ciguatera. Evaluation of the current knowledge on CFP among different populations groups, i.e. fishermen, residents and visitors, was also conducted through direct and indirect interviews. About half of the fishermen interviewed were actually able to identify risky fishing areas. While, overall, the CFP risk perception in the fishing community of Moorea seemed accurate, although not scientifically complete, it was sufficient for the safe practice of their fishing activities. This may be due in part to adaptive responses adopted by 36% of the fishermen interviewed, such as the avoidance of either high-risk fishing sites or toxic species. At the residents and visitors’ level, the study points out a striking lack of awareness of the CFP issue among visitors, as compared to local residents. Indeed, less than 25% of Moorea visitors vs. an average of 98% in residents were aware of CFP or of its presence on the island. Interestingly, evaluation of the fish consumption preferences showed that 70% of visitors do not consume lagoon fish during their stay, not for fear of CFP, but mainly due to the lack of availability of these species in recreational facilities or because they have nutritional preference for pelagic fish. This lack of awareness, along with the report by several CFP patients of the consumption of fish species yet banned for sale, stress the need for improved communication efforts on this critical issue among both residents and visitors on Moorea. The implementation of a public outreach strategy is proposed, based on both existing information networks and low-cost communication actions through information displays at various strategic locations, e.g. Tahiti-Faa’a international airport, the ferry boat station, recreational facilities, as well as the major trading points on Moorea Island.
ISSN: 1568-9883

hal-01391648
https://hal-univ-perp.archives-ouvertes.fr/hal-01391648
DOI : 10.1016/j.hal.2016.10.003

Résumé : La tuberculose, maladie très ancienne, est plus que jamais présentée sur la scène sanitaire mondiale avec 9 millions de nouveaux cas par an. Cette maladie, qui demeure une cause majeure de mortalité, est un des problèmes les plus difficiles à résoudre en santé publique et à échelle internationale. Les diverses programmes de lutte, lancés par l’Organisation Mondiale de la Santé (OMS), pour prévenir et garantir la guérison des patients tuberculeux, se heurtent à des difficultés qui hypothèquent leur efficacité. En effet, l'expansion du virus de rinimunodéficience humaine (VIII) et son influence néfaste sur la susceptibilité à la tuberculose, l'accroissement rapide de la tuberculose multirésistante, la pauvreté ainsi que la croissance démographique, sont un ensemble de facteurs préjudiciables à l'application des mesures préventives et curatives. Les contextes économiques difficiles conduisant indubitablement au cumul de ces facteurs, ont fait une césure entre les pays riches et les pays pauvres quant à l'incidence et la révolution de la tuberculose à échelle mondiale. Pour atténuer la disparité des résultats des luttes antituberculeuses, les méthodologies employées en épidémiologie de la tuberculose doivent s'inscrire dans une démarche d'efficacité. Les marqueurs moléculaires, indispensables à l'identification et à la classification des souches appartenant au complexe Mycobacterium tuberculosis (MTC) ont chacun des potentialités qui leur sont propres dont il convient de cerner pour une utilisation adéquate dans les études épidémiologiques et phylogénétiques. Le but de cette thèse consiste à extraire des connaissances nouvelles des résultats de génotypage stockées dans les bases de données, connaissances relatives au polymorphisme du support génomique pour estimer la contribution de chaque marqueur dans la classification de MTC. Le recours à différentes méthodes de reconstruction phylogénétique et de modélisation des données fut indispensable. A la lumière des résultats obtenus, cette thèse propose une nouvelle méthodologie de classification, pour rétablissement d'une phylogéographie robuste de MTC en relation avec l'histoire des migrations humaines qui aurait débutée en Afrique subsaharienne. Chaque méthode de génotypage ayant une efficience et un cout propres, qu'il convient de mesurer par rapport aux moyens disponibles et aux résultats escomptes, il est donc intéressant de renforcer la connaissance des marqueurs et de proposer différentes alternatives menant à la classification des mycobactéries. Ainsi, les résultats obtenus dans cette thèse apportent plus de cohérence aux solutions proposées pour la caractérisation des clones de MTC circulant dans le monde.
Tuberculosis, very old disease, is more than ever presented on the global health scene with 9 million new cases per year. This disease, which remains a major cause of mortality is one of the most intractable public health and international issues. The various control programs, launched by the World Health Organization (WHO) to prevent and guarantee the cure of tuberculosis patients face difficulties that undermine their effectiveness. Indeed, the expansion of human virus rinimunodéficience (VIII) and its negative influence on susceptibility to tuberculosis, the rapid growth of multidrug-resistant tuberculosis, poverty and population growth, are a set of factors detrimental to application of preventive and curative measures. The difficult economic circumstances undoubtedly leading to accumulation of these factors have a break between rich and poor countries about the impact and the revolution of tuberculosis worldwide. To address the disparity of the results of tuberculosis struggles, the methodologies used in epidemiology of tuberculosis must be part of a process efficiency. Molecular indispensable to the identification and classification of strains belonging to the Mycobacterium tuberculosis complex (MTC) markers each have their own potentials that need to be identified for proper use in epidemiological and phylogenetic studies. The purpose of this thesis is to extract new knowledge of the results of genotyping data stored in databases, knowledge of the polymorphism of genomic carrier to estimate the contribution of each marker in the classification of TCM. The use of different methods of phylogenetic reconstruction and modeling data was essential. In light of the results obtained, the thesis proposes a new classification methodology for a robust recovery phylogeography of TCM in connection with the history of human migration have started in sub-Saharan Africa. Each genotyping method with cost efficiency and equity, should be measured in relation to the resources available and discounts results, it is interesting to strengthen the knowledge of markers and propose alternatives leading to the classification of mycobacteria. Thus, the results obtained in this thesis bring more coherence to the proposed characterization of clones MTC circulating worldwide solutions.

http://www.theses.fr/2012AGUY0518/document

Éditeur(s) : HAL CCSD
Résumé : International audience
Background: In French Guiana, a recent study has shown that a major part of the histoplasmosis incidence temporal fluctuations could be explained by climatic factors and thus postulated that disseminated histoplasmosis cases could be in a large proportion due to new infections. The description of the seasonal pattern of histoplasmosis could potentially help to test this new hypothesis. Patients and methods: A study using prospective data from the French Hospital Database for HIV was conducted in order to determine seasonal variations of the incidence of first cases of disseminated histoplasmosis in HIV persons in Cayenne, French Guiana. Single failure Cox proportional hazards models were used. Results: After adjusting for CD4 counts and antiretroviral treatment, the incidence of disseminated histoplasmosis was significantly higher during the Short Wet Season-Long Dry Season than during the Short Dry Season-Long Wet Season (Adjusted Hazard ratio 1.7 (1.1-2.5), P= 0.01). Conclusion: This result gives both valuable epidemiologic information to clinicians and a supplementary argument in favour of the hypothesis that an important proportion of cases were due to recent exposure. Therefore, the use of a primary prophylaxis must be discussed in French Guiana.
J AIDS Clinic Res

Droits : info:eu-repo/semantics/OpenAccess
inserm-00915009
http://www.hal.inserm.fr/inserm-00915009
http://www.hal.inserm.fr/inserm-00915009/document
http://www.hal.inserm.fr/inserm-00915009/file/2012_Hanf_-_Disseminated_Histoplasmosis_seasonal_incidence_variations_a_supplementary_argument_for_recent_infection.pdf
DOI : 10.4172/2155-6113.1000175

Éditeur(s) : HAL CCSD
Résumé : International audience
BACKGROUND: Africa faces a number of unique environmental challenges. Unfortunately, it lacks the infrastructure needed to support the comprehensive environmental studies that could provide the scientific basis to inform environmental policies. There are a number of known sources of endocrine-disrupting chemicals (EDCs) and other hazardous chemicals in Africa. However, a coordinated approach to identify and monitor these contaminants and to develop strategies for public health interventions has not yet been made. OBJECTIVES: This commentary summarizes the scientific evidence presented by experts at the First African Endocrine Disruptors meeting. We describe a "call to action" to utilize the available scientific knowledge to address the impact of EDCs on human and wildlife health in Africa. DISCUSSION: We identify existing knowledge gaps about exposures to EDCs in Africa and describe how well-designed research strategies are needed to address these gaps. A lack of resources for research and a lag in policy implementation slows down intervention strategies and poses a challenge to advancing future health in Africa. CONCLUSION: To address the many challenges posed by EDCs, we argue that Africans should take the lead in prioritization and evaluation of environmental hazards, including EDCs. We recommend the institution of education and training programs for chemical users, adoption of the precautionary principle, establishment of biomonitoring programs, and funding of community-based epidemiology and wildlife research programs led and funded by African institutes and private companies. https://doi.org/10.1289/EHP1774.
Environmental Health Perspectives

hal-01616487
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01616487
DOI : 10.1289/EHP1774
PUBMED : 28935616

Éditeur(s) : HAL CCSD
Résumé : International audience
BACKGROUND: Dairy working increases the prevalence of lower airway respiratory diseases, especially COPD and asthma. Epidemiological studies have reported that chronic inhalation of organic dusts released during specific daily tasks could represent a major risk factor for development of these pathologies in dairy workers. Knowledge on size, nature and biological activity of such organic dusts remain however limited. OBJECTIVE: To compare size distribution, microbial composition and cellular effects of dusts liberated by the spreading of straw bedding in five French dairy farms located in Brittany. RESULTS: Mechanized distribution of straw bedding generated a cloud of inhalable dusts in the five dairy farms' barns. Thoracic particles having a 3-7.5µm size constituted 58.9-68.3% of these dusts. Analyses of thoracic dusts by next generation sequencing showed that the microbial dust composition differed between the five French farms, although Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria represent more than 97.5% of the bacterial phyla detected in each sample. Several bacteria genera comprising of human pathogenic species, such as Pseudomonas, Staphylococcus, Thermoactinomyces or Saccharopolyspora were identified. Cladosporium and Alternaria fungal genera, which are potent environmental determinants of respiratory symptoms, were detected in dusts collected in the five farms and their levels reached 15.5-51.1% and 9-24.7% of assignable fungal sequences in each sample, respectively. Finally, all dust samples significantly and strongly increased the expression of the pro-inflammatory TNF-α, IL-1β, IL-6 and IL-8 cytokines at both mRNA and protein levels in human monocyte-derived macrophages. Their effects were dose-dependent and detectable from 1µg/ml. The intensity of the macrophage responses however differed according to the samples. CONCLUSIONS: Our results strengthen the hypothesis that organic dusts released during the distribution of straw bedding are mainly constituted of thoracic particles which are small enough to deposit on lower bronchial epithelium of dairy farmers and induce inflammation.
Environmental Research

hal-01579610
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01579610
DOI : 10.1016/j.envres.2017.07.025
PUBMED : 28735230

Éditeur(s) : HAL CCSD
Résumé : International audience
Chronic obstructive pulmonary disease (COPD) is the chronic respiratory disease with the most important burden on public health in terms of morbidity, mortality and health costs. For patients, COPD is a major source of disability because of dyspnea, restriction in daily activities, exacerbation, risk of chronic respiratory failure and extra-respiratory systemic organ disorders. The previous French Language Respiratory Society (SPLF) guidelines on COPD exacerbations were published in 2003. Using the GRADE methodology, the present document reviews the current knowledge on COPD exacerbation through 4 specific outlines: (1) epidemiology, (2) clinical evaluation, (3) therapeutic management and (4) prevention. Specific aspects of outpatients and inpatients care are discussed, especially regarding assessment of exacerbation severity and pharmacological approach.
Revue Des Maladies Respiratoires

hal-01560287
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01560287
DOI : 10.1016/j.rmr.2017.03.034
PUBMED : 28552256

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
ETHNOPHARMACOLOGICAL RELEVANCE: Cutaneous leishmaniasis is a neglected disease with a high incidence in French Guiana, mainly in the middle and upper Oyapock basin, where Amerindian and some Brazilian people live. The main goals of this work were (i) to assess the knowledge about leishmaniasis in the different populations of the middle and upper Oyapock basin, (ii) to study the therapeutic strategies adopted by people affected by leishmaniasis and (iii) to document the use of phytotherapeutic remedies for leishmaniasis. Knowledge, attitudes and practices (K.A.P.) related to this disease and its treatments have been studied according to cultural group and geographical settlement. Within the Wayãpi group, the evolution of the knowledge of phytoremedies over the last 20 years has been characterised by literature-based comparisons. MATERIALS AND METHODS: A total of 144 questionnaires were administered in all the villages of the upper Oyapock and Camopi basins. Correspondence analyses were used for multivariate analysis. Plant species were identified at the Cayenne Herbarium (CAY). RESULTS: The biomedical concept of leishmaniasis correlates well with the Teko and Wayãpi concepts of kalasapa and kalasapau. Although the vector of this disease was not correctly identified, the most commonly cited aetiology (74.5%) was vector-borne, and related epidemiological schemes correlate well with the one encountered in French Guiana. Theoretically and practically, health centres were the most commonly used resource for diagnostic in instances of leishmaniasis infection (65.9%), independently of the patient's cultural group, along with the use of pharmaceutical drugs (85.3%). Pharmaceuticals were commonly utilised despite the frequent (51.5%) use of phytotherapeutic remedies, alone or in combination with drugs. The most cited medicinal plant species for the treatment of leishmaniasis included Eleutherine bulbosa (Mill.) Urb. (Iridaceae, cited 14 times), Euterpe oleracea Mart. (Arecaceae, 9), Cecropia obtusa Trecul (Cecropiaceae, 8), Jatropha curcas L. (Euphorbiaceae, 7), Ceiba pentandra (L.) Gaertn. (Bombacaceae, 6) and Carica papaya L. (Caricaceae, 6). Multiple correspondence analyses demonstrated that the species used in leishmaniasis remedies are more prone to vary by the user's place of residence than by their cultural origin, which indicates that exchange of knowledge about leishmaniasis remedies has occurred across different cultural groups. Literature-based comparisons between the remedies for leishmaniasis used by the Wayãpi during the 1980s showed a striking evolution, both in terms of diversity of species and number of plants used. The large number of species shared with other Guianese groups argues for intercultural exchange and may explain the majority (57.1%) of the newly used species highlighted in our study. CONCLUSIONS: Leishmaniasis is a well-known disease in the studied area. Phytotherapeutic treatments are still in use, although they are not the main source of remedies, and should undergo pharmacological studies to evaluate their potential therapeutic value.
ISSN: 0378-8741

pasteur-00634597
https://hal-riip.archives-ouvertes.fr/pasteur-00634597
DOI : 10.1016/j.jep.2011.07.044
PUBMED : 21816216

Éditeur(s) : HAL CCSD Nature Publishing Group
Résumé : International audience
The etiology of congenital heart defect (CHD) combines environmental and genetic factors. So far, there were studies reporting on the screening of a single gene on unselected CHD or on familial cases selected for specific CHD types. Our goal was to systematically screen a proband of familial cases of CHD on a set of genetic tests to evaluate the prevalence of disease-causing variant identification. A systematic screening of GATA4, NKX2-5, ZIC3 and Multiplex ligation-dependent probe amplification (MLPA) P311 Kit was setup on the proband of 154 families with at least two cases of non-syndromic CHD. Additionally, ELN screening was performed on families with supravalvular arterial stenosis. Twenty-two variants were found, but segregation analysis confirmed unambiguously the causality of 16 variants: GATA4 (1 x), NKX2-5 (6 x), ZIC3 (3 x), MLPA (2 x) and ELN (4 x). Therefore, this approach was able to identify the causal variant in 10.4% of familial CHD cases. This study demonstrated the existence of a de novo variant even in familial CHD cases and the impact of CHD variants on adult cardiac condition even in the absence of CHD. This study showed that the systematic screening of genetic factors is useful in familial CHD cases with up to 10.4% elucidated cases. When successful, it drastically improved genetic counseling by discovering unaffected variant carriers who are at risk of transmitting their variant and are also exposed to develop cardiac complications during adulthood thus prompting long-term cardiac follow-up. This study provides an important baseline at dawning of the next-generation sequencing era.
ISSN: 1018-4813

hal-01404211
https://hal-univ-bourgogne.archives-ouvertes.fr/hal-01404211
DOI : 10.1038/ejhg.2015.105
PUBMED : 26014430

Éditeur(s) : HAL CCSD American Society for Microbiology
Résumé : International audience
Summary: The apicomplexan parasite Toxoplasma gondii was discovered a little over 100 years ago, but knowledge of its biological life cycle and its medical importance has grown in the last 40 years. This obligate intracellular parasite was identified early as a pathogen responsible for congenital infection, but its clinical expression and the importance of reactivations of infections in immunocompromised patients were recognized later, in the era of organ transplantation and HIV infection. Recent knowledge of host cell-parasite interactions and of parasite virulence has brought new insights into the comprehension of the pathophysiology of infection. In this review, we focus on epidemiological and diagnostic aspects, putting them in perspective with current knowledge of parasite genotypes. In particular, we provide critical information on diagnostic methods according to the patient's background and discuss the implementation of screening tools for congenital toxoplasmosis according to health policies.
ISSN: 0893-8512

hal-00696903
https://hal.archives-ouvertes.fr/hal-00696903
https://hal.archives-ouvertes.fr/hal-00696903/document
https://hal.archives-ouvertes.fr/hal-00696903/file/Epidemiologysur and_Diagnostic-accepted.pdf
DOI : 10.1128/CMR.05013-11

Éditeur(s) : HAL CCSD
Résumé : International audience
Background/Aim Epidemiological studies reported that prenatal solvent exposure was associated with higher frequency of attention deficit and higher levels of hyperactivity or impulsivity in exposed children which suggest impaired motor inhibition function. The purpose of the present work is to investigate the effect of prenatal exposure to solvents on the motor inhibition function measured by neuropsychological test performed in children of 10-12 years old.
International Society of Environmental Epidemiology
Sydney, Australia

inserm-01578507
http://www.hal.inserm.fr/inserm-01578507

Éditeur(s) : HAL CCSD
Résumé : Publié en septembre 2013 dans le "Journal de Gynécologie Obstétrique et Biologie de la Reproduction" vol.42 n°5 p.413-444
We review the epidemiological literature on the possible impact of chemical and physical factors on pregnancy outcome. Effects of in-utero exposures on child health are not considered here. The highest levels of evidence concern the effects of passive smoking (on fetal growth), of lead (pregnancy-induced hypertension, fetal growth), of some Polychlorinated Biphenyls (PCB; on fetal growth) and, to a lesser extent, of atmospheric pollutants (on fetal growth and preterm delivery). For the other compounds, in particular non-persistent chemicals, the literature, which is generally based on poor exposure assessment, is less informative. In conclusion, the last decades have witnessed the development of mother-child cohorts in which exposure biomarkers have been assayed, allowing a large number of publications. For some persistent compounds, for which efficient exposure assessment approaches have been used, the literature indicates a likely impact on pregnancy outcomes. With the exception of air pollutants, the literature on non-persistent compounds is little conclusive; the assay of exposure biomarkers in repeated biological samples collected at relevant time points could help further increase knowledge regarding any health impact.
https://hal.archives-ouvertes.fr/hal-00916684

hal-00916684
https://hal.archives-ouvertes.fr/hal-00916684
https://hal.archives-ouvertes.fr/hal-00916684/document
DOI : 10.1016/j.jgyn.2013.02.012

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Whereas it is well established that prenatal exposure to polychlorinated biphenyls (PCBs) can disrupt children's behavior, early postnatal exposure has received relatively little attention in environmental epidemiology. To evaluate prenatal and postnatal exposures to PCB-153, a proxy of total PCB exposure, and their relation to inattention and activity in 5-year-old Inuits from the Cord Blood Monitoring Program. Prenatal exposure to PCBs was informed by cord plasma PCB-153 levels. We used a validated pharmacokinetic model to estimate monthly infants' levels across the first year of life. Inattention and activity were assessed by coding of video recordings of children undergoing fine motor testing. We used multivariable linear regression to evaluate the association between prenatal and postnatal PCB-153 levels and inattention (n=97) and activity (n=98) at 5years of age. Cord plasma PCB-153 was not associated with inattention and activity. Each interquartile range (IQR) increase in estimated infant PCB-153 levels at 2months was associated with a 1.02% increase in the duration of inattention (95% CI: 0.04, 2.00). Statistical adjustment for the duration of breastfeeding slightly increased regression coefficients for postnatal level estimates, some of which became statistically significant for inattention (months: 2-4) and activity (months: 2-5). Our study adds to the growing evidence of postnatal windows of development during which children are more susceptible to neurotoxicants like PCBs.
ISSN: 0160-4120

hal-01134338
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01134338
DOI : 10.1016/j.envint.2015.02.004
PUBMED : 25796081

Éditeur(s) : HAL CCSD
Résumé : Point processes are often used as spatial or spatio-temporal distribution models of occurrences. In this PhD dissertation, we focus first on Cox processes driven by a hidden process associated with a Dirichlet process. This model corresponds to hidden occurrences influencing the stochastic intensity of observed occurrences. We generalize the notion of "Shot noise Cox process" introduced by M{o}ller and develop its bayesian analysis by a Gibbs sampler combined with a Metropolis-Hastings algorithm. We show that our MCMC method is a reversible jump one. The model takes into account a random number of hidden contributions producing effects on the observed point process intensity. Therefore the parameter space has a variable dimension. We focus the statistical inference on the estimation of the hidden contribution expected value, the hidden contribution expected number, the spatial influence and correlation parameters. The contribution equality test and contribution independence test are proposed. Applications in epidemiology and ecology are shown from extit{Rubus fruticosa} data, extit{Ibicella lutea} data and death number data in counties of Georgia, USA. Two situations are considered with respect to available data~: firstly, the spatial positions of occurrences are observed between several pairs of consecutive dates; secondly, counts are carried out over a fixed time interval in several spatial sampling units. Secondly, we focus on point processes with memory introduced by Kagan, Ogata and Vere-Jones, pioneers in statistical seismology. In fact, spatio-temporal point processes play an important role in the studies of earthquake catalogs since they consist of seismic events with their dates and spatial locations. We studied an ETAS (Epidemic Type Aftershock Sequence) model with time independent background intensity and several triggering functions taking into account previous events. We illustrate our approach with a seismicity study of the Lesser Antilles arc. A comparaison study of Gamma, Weibull, Log-Normal and modified Omori law triggering function models is also carried out. We show that the modified Omori law does not fit the Lesser Antilles seismic data and the best adjusted triggering function is the Weibull model. Consequently, the waiting time between aftershocks is weaker in the Lesser Antilles zone compared to the one in regions with seismicity described by the modified Omori law. In other words, aftershock aggregativity is higher in the Lesser Antilles region. The stochastic background intensity following a Dirichlet process centered on a spatial log-normal process is discussed.
Les processus ponctuels sont souvent utilisés comme modèles de répartitions spatiales ou spatio-temporelles d'occurrences. Dans cette thèse, nous nous intéressons tout d'abord à des processus de Cox dirigés par un processus caché associé à un processus de Dirichlet. Ce modèle correspond à des occurrences cachées influençant l'intensité stochastique des occurrences observées. Nous généralisons la notion de " Shot noise Cox process " introduite par Moller et développons le traitement bayésien par un échantillonneur de Gibbs combiné à un algorithme de Metropolis-Hastings. Nous montrons que cette méthode MCMC est à sauts réversibles. Le modèle prend en compte, en effet, un nombre aléatoire de contributions cachées influençant l'intensité du processus ponctuel observé donc a un espace paramétrique de dimension variable. Nous focalisons l'inférence statistique sur l'estimation de la valeur espérée de chaque contribution cachée, le nombre espéré de contributions cachées, le degré d'influence spatiale de ces contributions et leur degré de corrélation. Le test d'égalité des contributions et celui de leur indépendance sont ainsi développés. L'utilité en épidémiologie et en écologie est alors démontrée à partir de données de Rubus fruticosa, Ibicella lutea et de mortalité dans les cantons de Georgia, USA. En termes de données observées, deux situations sont considérées: premièrement, les positions spatiales des occurrences sont observées entre plusieurs paires de dates consécutives; deuxièmement, des comptages sont effectués, au cours d'une période fixée, dans des unités d'échantillonnage spatiales. D'autre part, nous nous intéressons aux processus ponctuels à mémoire introduits par Kagan, Ogata et Vere-Jones, précurseurs de la statistique sismologique. En effet, les processus ponctuels spatio-temporels ont une place importante dans l'étude des catalogues sismiques puisque ces derniers sont généralement constitués d'événements sismiques datés et géo-référencés. Nous avons étudié un modèle ETAS (Epidemic Type Aftershock Sequence) avec une intensité d'arrière-plan indépendante du temps et plusieurs fonctions déclenchantes permettant d'intégrer les événements antérieurs récents. Cette approche est utilisée pour étudier la sismicité de l'arc des Petites Antilles. Une étude comparative des modèles Gamma, Weibull, Log-Normal et loi d'Omori modifiée pour les fonctions déclenchantes est menée. Nous montrons que la loi d'Omori modifiée ne s'ajuste pas aux données sismiques des Petites Antilles et la fonction déclenchante la plus adaptée est le modèle de Weibull. Cela implique que le temps d'attente entre répliques dans la zone des Petites Antilles est plus faible que celui des régions à sismicité décrite par la loi d'Omori modifiée. Autrement dit, l'agrégation des répliques après un événement majeur est plus prononcée dans la zone des Petites Antilles. La possibilité d'inclure une intensité d'arrière-plan suivant un processus de Dirichlet centré sur un processus spatial log-gaussien est discutée.
https://tel.archives-ouvertes.fr/tel-00841146

Droits : info:eu-repo/semantics/OpenAccess
NNT : 2012AGUY0555
tel-00841146
https://tel.archives-ouvertes.fr/tel-00841146
https://tel.archives-ouvertes.fr/tel-00841146/document
https://tel.archives-ouvertes.fr/tel-00841146/file/these_VALMY.pdf

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
UNLABELLED: ABSTRACT: BACKGROUND: Malaria remains a major health problem in French Guiana, with a mean of 3800 cases each year. A previous study in Camopi, an Amerindian village on the Oyapock River, highlighted the major contribution of environmental features to the incidence of malaria attacks. We propose a method for the objective selection of the best multivariate peridomestic landscape characterisation that maximises the chances of identifying relationships between environmental features and malaria incidence, statistically significant and meaningful from an epidemiological point of view. METHODS: A land-cover map, the hydrological network and the geolocalised inhabited houses were used to characterise the peridomestic landscape in eleven discoid buffers with radii of 50, 100, 200, 300, 400, 500, 600, 700, 800, 900 and 1000 metres. Buffer-based landscape characterisations were first compared in terms of their capacity to discriminate between sites within the geographic space and of their effective multidimensionality in variable space. The Akaike information criterion (AIC) was then used to select the landscape model best explaining the incidences of P. vivax and P. falciparum malaria. Finally, we calculated Pearson correlation coefficients for the relationships between environmental variables and malaria incidence, by species, for the more relevant buffers. RESULTS: The optimal buffers for environmental characterisation had radii of 100 m around houses for P. vivax and 400 m around houses for P. falciparum. The incidence of P. falciparum malaria seemed to be more strongly linked to environmental features than that of P. vivax malaria, within these buffers. The incidence of P. falciparum malaria in children was strongly correlated with proportions of bare soil (r = -0.69), land under high vegetation (r = 0.68) and primary forest (r = 0.54), landscape division (r = 0.48) and the number of inhabited houses (r = -0.60). The incidence of P. vivax malaria was associated only with landscape division (r = 0.49). CONCLUSIONS: The proposed methodology provides a simple and general framework for objective characterisation of the landscape to account for field observations. The use of this method enabled us to identify different optimal observation horizons around houses, depending on the Plasmodium species considered, and to demonstrate significant correlations between environmental features and the incidence of malaria.
ISSN: 1476-072X

inserm-00674075
http://www.hal.inserm.fr/inserm-00674075
http://www.hal.inserm.fr/inserm-00674075/document
http://www.hal.inserm.fr/inserm-00674075/file/1476-072X-10-65.pdf
DOI : 10.1186/1476-072X-10-65

Éditeur(s) : HAL CCSD
Résumé : Climate change is one of the biggest public health threats in the 21th century. An increase in temperatures will lead to an increase in mortality attributable to temperature. In addition, some populations and territories are particularly vulnerable to the impact of increases in heat. It is thus necessary to identify these populations and territories as well as examine future heat-Related health impacts in order to recommend equity-Oriented policies today and in the future. The general objective of this thesis is to document current and future heat-Related vulnerability factors in the context of climate change. In order to address this general objective, the thesis involved four components: a) to conduct a systematic review and a meta-Analysis to assess the heterogeneity in the heat-Mortality associations with respect to individual and contextual population characteristics; b) to identify whether and how the magnitude of mean temperature effects on all-Cause mortality were modified by chronic air pollution exposure, social deprivation, and a combination of these two dimensions; c) to develop a method to quantify the climate change impacts on heat-Related mortality using climate modeling; d) to assess historical and future social disparities in years of life lost caused by ambient temperature in Montreal and Paris, and compare these estimates as well as the impact of climate change on social disparities between the two cities. This thesis highlights which populations are more vulnerable to heat and shows that several differences exist with regard to guidelines from international public health institutions for the identification of vulnerable populations. This thesis also identified chronic air pollution exposure as a new vulnerability factor in heat-Related mortality and that it has a double interaction with social deprivation. Furthermore, in this thesis a novel method to quantify future heat-Related mortality was developed which emphasized the strong evidence of an increase in heat-Related mortality under climate change. This method was then applied to estimate the increase in daily years of life lost social disparities in both Montreal and Paris under climate change which showed that this increase would be greater in Montreal compared to Paris in the future. Thus, this thesis which used a variety of epidemiologic methods has clarified which populations are particularly vulnerable to heat impacts and challenges guidelines for the identification of vulnerable populations from international public health institutions. It has also highlighted the climate change impacts on health inequalities and aims to reorient equity-Focused policies.
Les changements climatiques constituent l’un des enjeux les plus importants en santé publique du XXIème siècle. En effet, une hausse des températures provoquera une hausse de la mortalité attribuable à la chaleur. En outre, certaines populations et territoires sont particulièrement vulnérables aux effets de la chaleur. Il est donc nécessaire de les identifier clairement ainsi que les impacts futurs pour orienter avec équité les politiques publiques aujourd’hui et à l’avenir. L’objectif de cette thèse est de documenter les facteurs de vulnérabilité à la chaleur dans le présent et les éléments permettant leur prise en compte pour l’avenir dans le contexte des changements climatiques. Quatre étapes ont été menées pour répondre à cet objectif : a) Mener une revue systématique et une méta-Analyse des facteurs de vulnérabilité face aux risques de mortalité en lien avec la chaleur ; b) Analyser si l’exposition chronique à la pollution atmosphérique modifie la relation entre la chaleur et la mortalité dans un contexte urbain (Paris) et explorer la double interaction avec la défaveur sociale ; c) Développer une méthode de quantification des impacts liés à la chaleur en lien avec les changements climatiques en intégrant une grande diversité de simulations climatiques ; d) Estimer les inégalités d’années de vies perdues attribuables à la chaleur et leurs projections futures dans deux contextes distincts (Montréal et Paris) et comparer ces inégalités. Cette thèse a permis de mettre en évidence sur la base de la littérature épidémiologique les groupes de population qui sont les plus vulnérables face aux effets de la chaleur et de montrer qu’il y a plusieurs divergences par rapport aux recommandations émises par les institutions de santé publique vis-À-Vis de l’identification de populations vulnérables. Cette thèse a permis également d’identifier l’exposition chronique à la pollution atmosphérique comme nouveau facteur de vulnérabilité à la chaleur et que cette vulnérabilité était encore plus prononcée lorsqu’il s’agissait de populations défavorisées socialement. Puis, une méthode permettant de quantifier l’impact des changements climatiques sur les décès attribuables à la chaleur et ses sources d’incertitudes a été développée, et a permis de mettre en évidence que la probabilité que les changements climatiques conduisent à une augmentation de la mortalité en lien avec la chaleur est très forte. Cette méthode a ensuite été utilisée pour estimer que l’augmentation de la température conduira à une augmentation des inégalités sociales d’années de vie perdues à la fois à Montréal et à Paris, l’effet des changements climatiques sur l’accroissement de ces inégalités étant plus fort à Montréal qu’à Paris. Cette thèse, en se basant sur diverses méthodes épidémiologiques, a permis dans l’ensemble de clarifier quelles populations étaient particulièrement à risque face aux effets de la chaleur et de questionner les recommandations émises par les organismes tels que l’OMS. Elle a également permis de montrer l’effet des changements climatiques sur l’évolution de vulnérabilités face à la chaleur pour inciter dès aujourd’hui la mise en place de politiques publiques équitables et limiter l’impact des changements climatiques sur l’accroissement des inégalités de santé.
https://tel.archives-ouvertes.fr/tel-01456772

Droits : info:eu-repo/semantics/OpenAccess
NNT : 2015PA11T003
tel-01456772
https://tel.archives-ouvertes.fr/tel-01456772
https://tel.archives-ouvertes.fr/tel-01456772/document
https://tel.archives-ouvertes.fr/tel-01456772/file/VA_BENMARHNIA_TARIK_05022015.pdf