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Additional file 1: Figure S1. Baseline prevalence (a) and infection intensity (b) according to the type of water access.

Additional file 2: Table S1. Tables of anova tests

International audience

International audience; Au Sénégal, nous avons développé depuis 10 ans une recherche basée sur l’observation et le transfert technologique, particulièrement la biologie moléculaire, la génomique, la culturomique et la protéomique avec l’utilisation du premier spectromètre de masse Maldi-TOF en microbiologie clinique en Afrique. Cette stratégie est associée à une politique de formation des étudiants du Sud et une aide à leur implantation au retour. Ces transferts de technologies et d’expertises ont permis d’explorer les causes des fièvres d’origine indéterminée, ainsi que le répertoire des agents infectieux chez l’homme et les arthropodes vecteurs, de diagnostiquer des maladies infectieuses en zone rurale grâce à des laboratoires Point of Care, d’isoler de nouvelles bactéries, ou encore d’étudier les pathologies liées aux grands rassemblements. Ils ont également permis de développer une recherche transdisciplinaire avec notamment l’étude du microbiote chez les enfants dénutris. Nous souhaitons poursuivre ce développement technologique qui sera la base d’une recherche de haut niveau au Sénégal.

International audience; Over the past decade, global malaria-related mortality has declined dramatically because of combined international actions that have defined and prioritized national and regional efforts to reduce the incidence of malaria, with the ultimate goal of eradication. Vector control strategies using insecticide-treated nets (ITNs) and indoor residual spraying (IRS) in African countries have contributed significantly to the declining incidence of malaria. However, the effectiveness of malaria control is threatened by increasing insecticide resistance and behavioral changes in Anopheles vectors. Thus, there is an urgent need to ensure that future programmes are designed to address these threats and protect the progress made so far in controlling malaria. This review summarizes the current malaria vector control tools and discusses about the critical threats to vector control programme and vector management.

Background: Urinary schistosomiasis is a parasitic disease that exists in all regions of Senegal. It is a major public health issue in this country. This study was carried out to determine the prevalence and intensity of this parasitosis in 12 villages of Niakhar (Fatick, Senegal). Methods: A total of 210 schoolchildren, aged 7 to 15 years, were enrolled in this study, and urine samples were examined for Schistosoma haematobium eggs using a standard urine filtration technique. Results: Of these children, 121 (57.6%) were found to be infected with a mean geometric count of 185 eggs per 10 ml of urine. The disease was present in all surveyed villages, and the prevalence ranged from 14.3% to 92.8%. The prevalence of infection was significantly correlated with increasing age and was higher in boys. Infection intensity was significantly higher in boys but did not significantly differ with age. Significant relationships between i) water contact or access to running water and ii) the prevalence or intensity of urinary schistosomiasis were also noted. Conclusions: The district of Niakhar is endemic for urinary schistosomiasis, with a high intensity of infection. A control program to decrease the prevalence and intensity should be implemented in this area to improve community health.

ObjectiveUsing human IgG antibody response to the Aedes Nterm-34kDa salivary peptide as an indicator of human exposure to Aedes bites in surveying exposed populations from areas at risk of dengue virus (DENV) transmission in urban settings of Vientiane city, Lao PDR. MethodsEnzyme-linked immunosorbent assay tests were performed to measure the IgG response to Nterm-34kDa peptide in blood samples collected within a flavivirus seroprevalence survey carried out in 2006 including 3558 randomly selected individuals. The level of IgG response to the Nterm-34kDa peptide in individuals was analysed in relation to the level of urbanisation of the individual's residence, areas that presented significant differences in the prevalence of recent DENV infection. ResultsNo differences were observed in the anti-Nterm-34kDa IgG level between DENV-positive and DENV-negative individuals. However, the level of specific IgG response was higher among individuals living in slightly urbanised neighbourhoods than among those in more highly urbanised areas (P

International audience; Study of the human antibody (Ab) response to Aedes salivary proteins can provide new biomarkers to evaluate human exposure to vector bites. The identification of genus- and/or species-specific proteins is necessary to improve the accuracy of biomarkers. We analysed Aedes albopictus immunogenic salivary proteins by 2D immunoproteomic technology and compared the profiles according to human individual exposure to Ae. albopictus or Ae. aegypti bites. Strong antigenicity to Ae. albopictus salivary proteins was detected in all individuals whatever the nature of Aedes exposure. Amongst these antigenic proteins, 68% are involved in blood feeding, including D7 protein family, adenosine deaminase, serpin and apyrase. This study provides an insight into the repertoire of Ae. albopictus immunogenic salivary proteins for the first time.

In tropical countries, malaria and hypertension are common diseases of pregnancy. They have physiopathologic similarities such as placental ischemia, endothelial dysfunction, and production of proinflammatory cytokines. Recent findings suggested their possible link. The authors conducted a case-control study to explore the relation between malaria and hypertension at Guediawaye, a hypoendemic malarial setting in Senegal. Cases were pregnant women admitted to the delivery unit for hypertension. Controls were pregnant women admitted for normal delivery, without any history of hypertension or proteinuria during the present pregnancy. Malarial infection was determined by placental tissue examination. From January to December 2002, 77 cases of gestational hypertension, 113 cases of preeclampsia, 59 cases of eclampsia, and 241 controls were enrolled. Placental malarial infection (PMI) was present in 14 cases (6.3%) and in 15 controls (6.2%). The prevalence of PMI was 4.6% for eclampsia, 4.0% for preeclampsia, and 11.6% for gestational hypertension. In multivariate analysis, PMI appeared to be an independent risk factor for gestational hypertension (adjusted odds ratio = 2.7, 95% confidence interval: 1.0, 7.6). The authors found an association between PMI and nonproteinuric hypertension in women living in a malaria-hypoendemic area. The exact significance of such relation should be clarified in further studies in different settings of malarial endemicity.

Background: During blood feeding, the mosquito injects saliva into the vertebrate host. This saliva contains bioactive components which may play a role in pathogen transmission and in host-vector relationships by inducing an immune response in the vertebrate host. The evaluation of human immune responses to arthropod bites might also represent a research direction for assessing individual exposure to the bite of a malaria vector. Methods: The present study examined the antibody ( Ab) IgG response during the season of exposure to Anopheles gambiae bites in young children living in a malaria endemic area. Immunoblots were performed with An. gambiae saliva to detect anti-saliva Ab bands and the evolution of immunogenic bands at the peak of, and following, the transmission period. Results: The results showed that anti-Anopheles Ab was directed against a limited number of salivary proteins ( 175, 115, 72 and 30 kDa bands). Specific IgG responses to mosquito salivary proteins were variable among exposed individuals; nevertheless, two major bands ( 175 and 72 kDa) were observed in all immune-responder children. Analysis of the intensity of immunogenic bands revealed that IgG levels against the 175 kDa band were significantly higher during the peak period compared to the end period malaria transmission. Conclusion: This preliminary work supports the potential of using anti-saliva immune responses as a measure of exposure to Anopheles bites. The use of immunoblots coupled with evaluation of band intensity could be an adequate tool for distinguishing immunogenic salivary proteins as candidate markers of bite exposure. Furthermore, this study may open the way to design new epidemiological tools for evaluating the risk of malaria exposure.

Placental Plasmodium falciparum sequestration is associated with dysregulated immune function. Placental inflammatory responses via IFN-gamma and TNF-alpha are implicated in functional damage. However, they are needed during placental infection to control asexual stage parasites. To test the hypothesis that placental immunomodulation associated with malaria disturbs cytokine secretion differently in monocytes and lymphocytes, we have determined the proportion of monocytes and/or lymphocytes secreting IFN-gamma, TNF-alpha, IL-10 and IL-12. Intervillous and peripheral blood monocyte (CD14(+)) and lymphocyte (CD3/CD4(+); CD3/CD8(+)) cytokine production was compared between 17 P. falciparum-infected and 12 non-infected Senegalese women. After culture with phorbolmyristate acetate/ionomycin (PMA/iono), lipopolysaccharide (LPS) or P. falciparum-infected erythrocytes (IE), the intracellular expression of cytokines in lymphocytes (IFN-gamma, TNF-alpha) and monocytes (IL-10, IL-12, TNF-alpha), was detected. In response to IE, CD4(+) and CD8(+) T-cells produced IFN-gamma and TNF-alpha at similar rates in both compartments. In response to PMA/iono, the frequencies of CD4(+) and CD8(+) T-cells producing IFN-gamma and TNF-alpha were similar in both compartments, but increased in P. falciparum-infected placentas. In response to LPS or IE, IL-12 secreting monocytes were increased in infected women, while the frequency of TNF-alpha secreting monocytes was decreased compared to that in non-infected placenta. The monocyte IL-12 response is not impaired in infected women. IL- 12 is an important factor for inducing IFN-gamma in T-cells. Thus, 1L-12 and IFN-alpha responses may synergistically allow a protective immune response in placental malaria. TNF-alpha production by CD4(+) and CD8(+) T-cells, is up-regulated in P falciparum-infected placentas, suggesting that T-cells actively participate to inflammatory responses.