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Dans un contexte de précarité économique où l’homme cherche à tirer sa survie de la nature, il doit chasser pour attraper le gibier, pêcher pour manger du poisson. Mais ces animaux que l’on chasse ou ces poissons que l’on pêche constituent aussi un danger pour l’homme. Car dans cette recherche des gibiers ou des poissons, il y a de ces espèces qui cherchent à se nourrir du sang de l’homme. C’est le cas des cercaires (les schistosomes). Même si l’homme ne va pas nécessairement chercher les nkodia pour faire la pêche, les activités de survie l’amènent parfois à les côtoyer sans le savoir. Comment l’homme peut-il se soustraire à ces activités pour éviter le risque de contamination à la schistosomiase ? Va-t-il éviter le maraichage, la pêche, la baignade et autres ? Mais s’il les abandonne, comment va-t-il survivre ? Ce sont toutes ces questions qui impliquent le rapprochement de l’homme et les nkodia et aussi privilégient les rapports homme-nkodia, avec tout cet arsenal d’activités qui mettent l’homme en contact avec les nkodia et peuvent favoriser la contamination aux schistosomes.

Introduction : Dans le district sanitaire (DS) de Kéniéba la prévalence de la schistosomiase est de 83,6% malgré plusieurs campagnes de distribution médicamenteuse de masse (DMM) de praziquantel. Ce travail a étudié les facteurs associés à la connaissance de la schistosomiase dans le DS de Kéniéba. Méthodes : Une étude transversale utilisant une approche qualitative et quantitative a été conduite de mai à juillet 2019 chez les 9 et 14 ans et adultes de 15 à 65 ans dans le DS de Kéniéba. Une régression logistique, des focus group de discussion et des entretiens individuels ont été conduits. Résultats : Sur un total de 822 participants, le sexe masculin était de 55,1% (86/156) chez les 9 et 14 ans et le sexe féminin représentait 58% (386/666) chez les adultes. L’âge médian des participants était de 33 ans. Les 51,2% (421/822) n’étaient pas scolarisés. Le sexe, l’âge, le risque d’attraper la schistosomiase, le canal d’information, l’habitude de participer aux DMM et la connaissance du mode de transmission étaient statistiquement associés à la connaissance de la schistosomiase. Conclusions : L’étude a rapporté une connaissance faible de la schistosomiase comme obstacle dans la lutte contre elle. Une éducation sanitaire intensive continue adaptée aux conditions socio-culturelles pour un changement de comportement serait nécessaire

Genital schistosomiasis is mainly located in the neck of the uterus and the vagina, less frequently on the vulva, the fallopian tubes and ovaries and rarely in the body of the uterus. We here report the case of a 10-year-old girl admitted with a swelling on the vulva in whom histological examination showed cutaneous schistosomiasis due to Schistosoma haematobium. Outcome was favorable with a single 40 mg/kg mg dose of praziquantel, with tumor regression. [ABSTRACT FROM AUTHOR]

Background: Schistosomiasis is endemic in Nigeria and three species; Schistosoma haematobium, Schistosoma mansoni, and Schistosoma intercalatum have been reported in Niger Delta, Nigeria. This study aimed to determine the prevalence of schistosomiasis in rural communities of Bayelsa State, Nigeria. Methodology: Four rural homogeneous communities; Otuegala, Immiringi, Otuesega, and Ibelebiri in Ogbia Local Government Area of Bayelsa State, Nigeria, were randomly selected for the study. A structured questionnaire was administered to each participant in their native language and used to collect participant's biodata and swimming history. Stool samples collected from all participants were examined qualitatively by wet preparation and after formolethol concentration. Data were analyzed using SPSS version 20.0 software and results presented in proportion and tables. Results: A total of 829 participants (age range 1 - 80 years) were recruited for the study. Helminth ova were identified in the stool samples of 218 (26.3%) participants. Among 380 males examined, 82 (21.6%) were infected, while out of 449 females examined, 138 (30.3%) were infected. The ova of seven helminths identified and their frequency of occurrence were; S. intercalatum 86 (10.4%), Ascaris lumbricoides 53 (6.4%), S. mansoni 35 (4.2%), Trichuris trichiura 22 (2.6%), hookworm 20 (2.4%) and Taenia spp 2 (0.2%). Schistosoma haematobium was identified in non-urine contaminated stool sample of an eight-year old boy. A total of 11 (1.3%) participants had double infections, affecting 7 (63.6%) females and 4 (36.4%) males, with the commonest combination being S. intercalatum and A. lumbricoides 6 (0.7%), followed by S. intercalatum and hookworm 4 (0.5%), and S. mansoni and hookworm 1 (0.1%). Conclusion: S. intercalatum was the most prevalent intestinal helminthic infection in this study, which is a rare finding in most epidemiological investigations. The affinity of Schistosoma species to establish double infections with hookworm and other intestinal helminths should be taken into account during chemoprophylaxis. [ABSTRACT FROM AUTHOR]

Copyright of African Journal of Reproductive Health is the property of Women's Health & Action Research Centre and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Résumé: Cette étude a porté sur la prévalence de la schistosomiase urinaire chez 307 écoliers âgés de 7 à 17 ans au niveau de différentes écoles de quatre localités de la région de Rosso. Parmi eux, 17,6 % (n = 54) avaient une hématurie et 15,6 % (n = 48) étaient porteurs d'œufs de Schistosoma haematobium. Selon le quartier, les taux de prévalence d'infection les plus élevés (p = 0,003) étaient observés chez les écoliers dans les quartiers de Breun (19,7 % ± 0,09), de Tounguen (18,6 % ± 0,08) et de PK 7 (18,4 % ± 0,08). Les taux d'hématurie et les charges parasitaires des écoliers étaient comparables pour l'âge et le sexe (p > 0,05). Les écoliers dans le quartier de Demeldek étaient significativement moins infectés que ceux des autres quartiers (5,3 % ± 0,11 ; p = 0,003). La charge parasitaire était comprise entre six et 15 œufs par 10 mL d'urine. Les prospections malacologiques effectuées au niveau des points d'eau de chaque site ont mis en évidence la présence des espèces suivantes : Bulinus truncatis , Bulinus forskalii , Lymnaea natalanis , Biomphalariae feifferi et Melanoides tuberculata. Ces résultats montrent que la schistosomose pose un problème de santé publique dans la région. Pour éradiquer cette parasitose, il faudra approfondir les études malacologiques et conjuguer plusieurs actions de prévention. This study assessed the prevalence of schistosomiasis among 307 schoolchildren aged from 7 to 17 years at various schools in four districts in the Rosso region. Hematuria was observed among 17.5% (54/307) and Schistosoma hematobium eggs were found among 15.6% (48/307). We observed the highest prevalence rates (P = 0.003) among schoolchildren in the districts of Breun (19.75% ± 0.09), Tounguen (18.66% ±0.08) and PK 7 (18.42 % ±0.08). The statistical analysis showed that the differences in the prevalence, hematuria rate, and parasite load did not differ significantly by the schoolchildren's age and sex (P > 0.05). Schoolchildren in Demeldek were significantly (P = 0.003) less infested (5.33% ± 0.11) than those in the other districts. The parasite load ranged from 6 to 15 eggs/10 ml of urine. The malacological investigations conducted at the water points of each village visited showed the presence of Bulinus truncatis, Bulinus forskalii, Lymnaea natalanis, Biomphalariae feifferi and Melanoides tuberculata. These results show that schistosomiasis poses a public health problem in the region. To eradicate this parasitosis, it will be necessary to conduct more detailed malacological studies and combine several types of preventive actions. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the usefulness of the WHO classification of ultrasound pathological changes and to establish risk factors for morbidity in a highly endemic setting.Methods: One hundred and fifty-seven ultrasounds were performed on school-aged children previously diagnosed with urinary schistosomiasis in Cubal, Angola. The findings were analysed according to the WHO guidelines. Factors for morbidity were studied.Results: Mean age of the children was 8.7 (SD 3.2) years. Pathological changes were found in 85.3% (84.7% in the bladder, 34.4% the ureter and 6.3% kidney lesions). The global score according to the WHO classification was 5.74. Male gender [OR 2.61 (1.04-6.58); P 0.043] and older age [OR 2.96 (1.17-7.46); P 0.023] were associated with a higher risk of developing any kind of urinary abnormality. Proteinuria was present in 61.7% of the children. Macroscopic haematuria [OR 2.48 (1.11-5.58); P = 0.02)] and a high level of proteinuria > 300 mg/dl [OR 5.70 (2.17-14.94); P 300 mg/dl)] were associated with abnormalities of the upper urinary tract and showed good positive and negative predictive values for the detection of pathology in the upper urinary tract (65.5% and 71.1%, respectively).Conclusions: Severe urinary tract pathology was found in a high percentage of the children in our setting. Microhaematuria and proteinuria were good markers of morbidity, proteinuria being more precise for severe alterations of the upper urinary tract. We suggest initial and evolutive ultrasound in children diagnosed with schistosomiasis, and close monitoring including periodic controls. As schistosomiasis control efforts are currently focused on reducing morbidity, tests that detect the presence or degree of morbidity are essential for targeting treatment and tracking the progress of control campaigns. [ABSTRACT FROM AUTHOR]

Objective: Interleukin-10 (IL-10) is an anti-inflammatory cytokine produced by Th1 cells and macrophages. The rationale of this study was to examine and validate possible contributions of IL-10 promoter polymorphisms in sub-Saharan Africa in children infected with either Plasmodium falciparum or Schistosoma haematobium and in children co-infected with both parasites.Materials and Methods: A total of 309 Nigerian children aged 4-15 years were recruited. The study group consisted of individuals infected either with P. falciparum (n = 76) or S. haematobium (n = 94) in mono-infections, a group of children co-infected with both P. falciparum and S. haematobium (n = 62) and matched healthy controls (n = 77). The IL-10 promoter polymorphisms -1082G/A, -819C/T and -592C/A were genotyped by direct sequencing.Results: The frequencies of the IL-10 -1082GG genotype, the -1082G allele and haplotype GCC (positions -1082, -819 and -592) were higher in children infected with P. falciparum than in healthy controls, indicating that the -1082GG genotype and the -1082G allele and the GCC haplotype are associated with increased susceptibility to malaria infection (OR = 3.4, 95% CI = 1.2-10.8, P = 0.02; OR = 2.5, 95% CI = 1.1-3.4, P = 0.02; OR = 3.8, 95% CI = 2.0-7.2, P = 0.0001, respectively). Children with the -1082GG genotype had a higher parasitaemia than children with the -1082AA or -1082AG genotypes (P = 0.0017). Haplotype GCC occurred more frequently in children infected with S. haematobium, while haplotype GTA was less frequent than in controls (OR = 2.2, 95% CI = 1.2-4.4, P = 0.017 and OR = 0.1, 95% CI = 0.02-0.5, P = 0.0004, respectively). No differences in the frequencies of IL-10 promoter polymorphisms were observed between children with P. falciparum-S. haematobium co-infections and healthy controls.Conclusion: Although IL-10 promoter polymorphisms are not associated with P. falciparum and S. haematobium co-infection, variant -1082G/A and haplotype GCC are associated with malaria, whereas the IL-10 haplotypes GCC and GTA are associated with schistosomiasis. [ABSTRACT FROM AUTHOR]

Objective: To determine the prevalence of schistosomiasis (SCH) and soil-transmitted helminths (STH) in the Democratic Republic of Congo, and to assess the capacity of the local health centres for diagnosis and treatment.Methods: Cross-sectional school-based survey in two health districts in the Province of Kwilu. We collected a stool and a urine sample for parasitological examination. Urine filtration and duplicate Kato-Katz thick smears were used for the diagnosis of SCH. Health centres were evaluated using a structured questionnaire.Results: In total, 526 children participated in the study and the overall prevalence of Schistosoma mansoni infection was 8.9% (95% CI: 3.5-13.2) in both districts. The prevalence was higher in Mosango (11.7%; 95% CI: 8.9-14.8) than Yasa Bonga district (6.2%; 95% CI: 1.1-11.4). Urine filtration showed that Schistosoma haematobium infection was not present. The combined STH infection prevalence was 58.1% in both districts; hookworm infection was the most common STH found in 52.9% (95% CI: 29.3-62.4) of subjects, followed by Ascaris lumbricoides 9.3% (95% CI: 5.8-15.5) and Trichuris trichiura 2.1% (95% CI: 0.9-4.9). Mixed STH infections were observed as well as SCH-STH coinfection.Conclusion: Further mapping of both SCH and STH burden is needed, and coverage of preventive chemotherapy in school-aged children should be increased. [ABSTRACT FROM AUTHOR]

INTRODUCTION: la schistosomiase, deuxième endémie parasitaire mondiale, est une parasitose due aux trématodes du genre Schistosoma. Nos objectifs étaient d'évaluer les prévalences des différentes espèces de schistosomes (Schistosoma mansoni, haematobium, et intercalatum) chez les écoliers, et d'identifier les facteurs de risques, les signes cliniques de la schistosomiase, et les mollusques hôtes intermédiaires des schistosomiases dans les eaux stagnantes. METHODES: l'étude était transversale et s'est déroulée sur 3 mois. Elle consistait en l'enregistrement des données sociodémographiques et cliniques, le prélèvement des échantillons de selles et d'urines, la recherche des mollusques et le traitement des écoliers positifs à dautres helminthes. Les examens de laboratoire se sont déroulés à l'Institut de recherches Médicales et d'études des Plantes Médicinales à Yaoundé où on examinait les échantillons de selles et d'urine par les méthodes de KATO KATZ et de centrifugation respectivement, et un malacologiste déterminait l'espèce des mollusques. RESULTATS: au total, 400 élèves âgés entre 8-16 ans, soit 223 (55.7%) filles et 177 (44.3%) garçons répartis dans 4 écoles primaires ont participé à l'étude. L'enquête sociale a révélé que 154 écoliers sur 400 (soit 38.5%) étaient en contact avec les eaux de rivière au moins une fois par semaine, dont 58% aux environs de midi. Tous les élèves avaient au moins un signe de schistosomiase bien que non spécifique prédominé par des douleurs abdominales à 72% (n= 288 sur 400). Sur le plan biologique aucun euf de schistosomiase n'a été mis en évidence. Le taux d'émission de cercaire était négatif chez les 100 espèces aquatiques retrouvées. CONCLUSION: l;aire de santé de Santchou n'est pas un foyer actif de schistosomiase, mais reste une zone à risque du fait de la riziculture et de la présence des eaux stagnantes. L'intensification des campagnes d'éducation sanitaire dans la population permettrait de retarder la survenue de cette parasitose dans la localité.

Copyright of Biologie Aujourd'hui is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Schistosomiasis, the second endemic parasitic infection in the world, is a parasitosis caused by trematodes from the genus Schistosoma. Our study aims to assess the prevalence of different species of schistosomes (Schistosoma mansoni, haematobium and intercalatum) among schoolchildren and to identify risk factors, clinical signs of schistosomiasis, and schistosomiasis intermediate host snails in stagnant water. Methods: We conducted a cross sectional study over a three months period. The study consisted of sociodemographic and clinical data recording, collection of stool samples and urine, molluscan research and treatment of positive students for other helminths. Laboratory tests were performed at the Medical Research Institute and the study of Medicinal Plants in Yaounde where stool samples and urine were examined using KATO KATZ and centrifugation technique respectively, and shellfish species were determined by a malacologist. Results: A total of 400 students aged between 8-16 years, 223 (55.7%) girls and 177 (44.3%) boys attending 4 elementary school were enrolled in the study. The social survey revealed that 154 students out of 400 (or 38.5%) were in contact with the river water at least once a week, 58% from around noon. All students had at least one symptom of schistosomiasis although nonspecific and dominated by abdominal pain in 72% of cases (n = 288 of 400). Biologically, no schistosomiasis eggs were detected. Cercaria releasing rate was negative in the 100 watery species found. Conclusion: The Santchou health area is not an active outbreak of schistosomiasis, but remains a risk area because of rice cultivation and stagnant water. The intensification of health education campaigns among the general population would delay the onset of this infection in the locality. [ABSTRACT FROM AUTHOR]

Objectives The human mannose-binding lectin ( MBL) and ficolins ( FCN) are involved in pathogen recognition in the first line of defence. They support activation of the complement lectin cascade in the presence of MBL-associated serine protease 2 ( MASP-2), a protein that cleaves the C4 and C2 complement components. Recent studies found that distinct MBL2 and FCN2 promoter variants and their corresponding serum levels are associated with relative protection from urogenital schistosomiasis. Methods We investigated the contribution of MASP-2 levels and MASP2 polymorphisms in a Nigerian study group, of 163 individuals infected with Schistosoma haematobium and 183 healthy subjects. Results MASP-2 serum levels varied between younger children (≤12 years) and older children (>12 years) and adults ( P = 0.0001). Younger children with a patent infection had significantly lower MASP-2 serum levels than uninfected children ( P = 0.0074). Older children and adults (>12 years) with a current infection had higher serum MASP-2 levels than controls ( P = 0.032). MBL serum levels correlated positively with MASP-2 serum levels ( P = 0.01). MASP2 secretor haplotypes were associated with MASP-2 serum levels in healthy subjects. The heterozygous MASP2 p.P126L variant was associated with reduced serum MASP-2 levels ( P = 0.01). Conclusions The findings indicate that higher MASP-2 serum levels are associated with relative protection from urogenital schistosomiasis in Nigerian children. [ABSTRACT FROM AUTHOR]

Objectives: Recent reports suggest that Schistosoma infection may increase the risk of acquiring human immunodeficiency virus (HIV). We used data from a large cross-sectional study to investigate whether Schistosoma mansoni infection is associated with increased HIV prevalence.Methods: We conducted a household survey of residents in island fishing communities in Mukono district, Uganda, between October 2012 and July 2013. HIV status was assessed using rapid test kits. Kato-Katz (KK) stool tests and urine-circulating cathodic antigen (CCA) were used to test for Schistosoma infection. Multivariable logistic regression, allowing for the survey design, was used to investigate the association between S. mansoni infection and HIV infection.Results: Data from 1412 participants aged 13 years and older were analysed (mean age 30.3 years, 45% female). The prevalence of HIV was 17.3%. Using the stool Kato-Katz technique on a single sample, S. mansoni infection was detected in 57.2% (719/1257) of participants; urine CCA was positive in 73.8% (478/650) of those tested. S. mansoni infection was not associated with HIV infection. [KK (aOR = 1.04; 95% CI: 0.74-1.47, P = 0.81), CCA (aOR = 1.53; 95% CI: 0.78-3.00, P = 0.19)]. The median S. mansoni egg count per gram was lower in the HIV-positive participants (P = 0.005).Conclusions: These results add to the evidence that S. mansoni has little effect on HIV transmission, but may influence egg excretion. [ABSTRACT FROM AUTHOR]

Abstract: Schistosome worms inhabit mammalian mesenteric veins. Their eggs cause chronic inflammation, which progresses to periportal fibrosis in 5 to 30% of cases, increasing portal blood pressure and leading to esophageal varices. Episodes of bleeding cause hepatic necrosis and may ultimately lead to hepatic failure and the death of the patient. Schistosome infections can also cause pulmonary hypertension and heart failure. The mechanisms of fibrogenesis and fibrolysis are beginning to be unraveled, but it remains unclear why disease occurs only in certain subjects, as also observed for other types of chronic liver inflammation, as in hepatitis C or B. We summarize here the results that showed that fibrosis progression is determined by a genetic locus on chromosome 6. The CCN2 gene at this locus, encodes CTGF that is a crucial regulator of fibrosis. Two groups of CCN2 polymorphisms independently modulate the progression of hepatic fibrosis. These results were obtained in an Asian population, but were extended to humans living in Africa and South America and are presently tested in liver fibrosis of other etiological origins. [Copyright &y& Elsevier]

Objectives To evaluate the utility of a simple questionnaire and urine reagent strip testing for the rapid diagnosis of Schistosoma haematobium in rural northern Ghana. Methods Cross-sectional parasitological and questionnaire survey in a community in northern Ghana. Participants provided two urine specimens that were examined under a microscope using a centrifugation method. The first urine sample was additionally subjected to reagent strip testing. A short questionnaire was administered to all participants. Results Microscopy of urine samples obtained from 208 individuals aged 1-77 years revealed an S. haematobium prevalence of 6.8%. The presence of any blood or protein on a urine reagent strip was 100% and 42% sensitive, and 93% and 80% specific for S. haematobium diagnosis. Questionnaires were completed by 198 individuals. Self-reported haematuria showed a sensitivity of 53% and a specificity of 85%. A dichotomous two-question panel was helpful in S. haematobium diagnosis, with working and playing near the river significantly associated with S. haematobium infection ( P < 0.001). Conclusion The use of urine reagent strips, coupled with questions pertaining to water contact patterns, might be considered for point-of-contact diagnosis of S. haematobium where microscopy is unavailable. [ABSTRACT FROM AUTHOR]

Objective To conduct a nationwide integrated neglected tropical disease (NTD) prevalence survey to define the need for public health interventions using an innovative mapping protocol. Methods Two villages were selected in every peripheral health unit in endemic districts: 29 districts for schistosomiasis and STH, 15 of them for trachoma. In each village, 15 children aged 6-9 years at a randomly selected school were tested. An additional convenience sample of 35 children aged 1-5 years underwent an eye examination for trachoma. This integrated mapping was followed by a 20-cluster trachoma survey in each district that surpassed the WHO-defined threshold of 10% prevalence of trachomatous inflammation-follicular (TF). Results A total of 1096 villages were surveyed in <6 weeks. The district prevalence of schistosomiasis ranged from 2 to 49% and of STH from 5 to 70%, with prevalence at the village level ranging from 0 to 100% for both diseases. Two districts passed the threshold of 10% for active trachoma, but the cluster survey indicated this was because of misclassification bias and that the real prevalence was <1%. Conclusion Results of this mapping were used by the MoH and partners to plan integrated mass drug administration (MDA). Mass drug administration for trachoma was not implemented as no district passed the threshold requiring public health intervention. [ABSTRACT FROM AUTHOR]

Copyright of West African Journal of Medicine is the property of West African Journal of Medicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objectives The murine model of Schistosoma mansoni infection is characterized by strong fibrosis and little hepatocellular injury. The objective of this study was to evaluate the potential link between hepatic schistosomiasis and bile duct injury in relation to the expression of profibrotic cytokines and fibrosis-related genes. Methods Hepatic schistosomiasis was induced via percutaneous infection of mice with 50 S. mansoni cercariae. Markers of fibrosis including matrixmetalloproteinases (MMPs) and tissue-inhibitors of metalloproteinases (TIMPs), as well as markers of bile duct injury (keratin-19, VCAM-1) were studied during 24 weeks after infection by RT-PCR and immunohistochemistry. Results Liver biochemistry revealed no differences in serum transaminase and alkaline phosphatase levels in infected and uninfected mice. Total liver hydroxyproline content was increased 5-fold ( P < 0.05) after infection. Gene expression analysis revealed MMP-2 (12-fold, P < 0.05) and TIMP-1 (48-fold, P < 0.05) up-regulation after infection. The balance of MMP and TIMP was shifted towards TIMP. Bile ducts were engulfed by adjacent granulomas resulting in ductular proliferation (keratin-19). VCAM-1 expression and inflammatory infiltrates were reduced. Conclusions This study demonstrates that schistosomiasis is associated with (i) an imbalance of MMP-2 and TIMP-1 as key players of fibrogenesis and (ii) with secondary bile duct alterations leading to ductular proliferation possibly contributing to fibrosis. [ABSTRACT FROM AUTHOR]

Objective To examine the role of socioeconomic situation in influencing the risk and intensity of infection with Schistosomiasis mansoni. Methods Cross-sectional study in Walukuba Division bordering Lake Victoria, Jinja District. We assessed a random sample of 463 individuals aged 10–20 years for Schistosoma mansoni infection, water contact behaviour and treatment status with praziquantel as of the last mass treatment. Socioeconomic conditions of the participants’ households were assessed by calculating a wealth index (based on type of housing and ownership of assets). Households were classified in four classes; multivariate logistic regression analysis was used to identify independent predictors of being infected with schistosomiasis. Intensities of infection with S. mansoni were compared across the classes of wealth index. Results Wealth index emerged a risk factor for infection with S. mansoni after controlling for water contact and treatment with praziquantel. The adjusted odds ratio of being infected for the lowest level of wealth index compared to the highest was 10.42 (95% CI 3.38–32.36 P < 0.001). The intensity of infection decreased with wealth index Linearity F-ratio 13.91, 1 df, P < 0.001). The geometric egg count for those in the lowest wealth index was 230 (95% CI 199–279) compared to 114 (95% CI 80–162) for the highest wealth index. Conclusions In addition to mass treatment with praziquantel, improving the socio-economic conditions of the population should be given priority. [ABSTRACT FROM AUTHOR]

Objective To investigate trends in the efficacy of praziquantel (PZQ) suggestive of the emergence of drug resistance against Schistosoma mansoni infection after 12.5 years of intense, repeated use in a small geographic area along the shores of Lake Victoria. Methods As part of a longitudinal study, 178 men occupationally exposed to schistosomes were repeatedly tested for S. mansoni infection at 4- to 6-week intervals and treated with PZQ at each reinfection. We compared cure rates by year of study and examined factors associated with cure failure in a multivariate logistic regression model. Results Overall, the cure rate after a single dose of PZQ was 66%, ranging annually from 36% to 82%. In multivariate analysis, failure to cure after 1 PZQ dose was significantly associated with high intensity of infection and having fewer previous exposures to dying worms. Even after adjustment for these factors, treatments administered in 2006 were significantly more likely to result in cure failures than treatments administered in 2004, the year in which PZQ efficacy was highest. While cure rates varied over the course of 12 years, there was no consistent downward trend towards decreased efficacy over time. In years for which malacological data were available, periods of low PZQ efficacy coincide with high rates of S. mansoni infection in nearby snail populations. Conclusion We did not find a pattern of cure failures consistent with development of clinical resistance to PZQ in our intensely treated cohort. [ABSTRACT FROM AUTHOR]

Objectives To characterize age–gender prevalence profiles of urinary schistosomiasis according to the questionnaire responses, compare the profiles to field survey data from selected regions, and determine if the profiles varied spatially throughout Tanzania. Methods In 2004, a national school-based questionnaire survey for self-reported schistosomiasis and blood in urine (BIU) was conducted in all regions of mainland Tanzania, to assist targeted mass distribution of praziquantel. Field survey data were collected in six north-western and five coastal regions using microscopic examination of urine samples for the presence of Schistosoma haematobium eggs and assessment of micro-haematuria with chemical reagent strips. Bayesian logistic regression models were created to calculate age–gender profiles adjusted for demographic and ecological covariates and spatial correlation in the questionnaire data. Separate odds ratios (OR) for age–gender effects were calculated in each administrative area. Results Data were obtained from > 2.5 million schoolchildren. Boys had higher prevalence of self-reported schistosomiasis and BIU than girls. In boys, prevalence according to the questionnaire and field surveys followed similar age profiles. However, in girls, prevalence according to the field surveys increased in older age groups, but flattened out or decreased according to the questionnaire, indicating the latter underestimated prevalence in older girls. In the models, little spatial correlation was evident in the OR for the age–gender effects, suggesting that these did not vary spatially. Conclusion Age–gender patterns of urinary schistosomiasis were consistent in different geographical areas of Tanzania. Because the questionnaire underestimated prevalence in older girls, we propose that upward calibration of observed prevalence is done for older females only. [ABSTRACT FROM AUTHOR]

Objectives: Chronic exposure to malaria exacerbates Schistosoma mansoni-associated hepatosplenomegaly in school-aged children. However, residual hepatosplenomegaly after treatment of S. mansoni with concurrent mollusciciding suggests malaria could be an underlying cause of hepatosplenomegaly. We investigated the role of chronic malaria in childhood hepatosplenomegaly in the presence and absence of concurrent S. mansoni infection. Methods: Cross-sectional study of children in an study area where transmission of S. mansoni, but not malaria, is restricted to the eastern end. Clinical and ultrasound examinations were conducted, and parasitological and serological tests used to determine S. mansoni infection intensities and comparative exposure levels to malaria. Results: Chronic exposure to malaria, as determined by Pfs-IgG3 levels, was associated with hepatosplenomegaly even in the absence of S. mansoni infection. Children infected with S. mansoni mostly had light to moderate infection intensities but greater enlargement of the liver and spleen than children who did not have schistosomiasis, and for the left liver lobe this was S. mansoni infection intensity dependent. Conclusions: Children chronically exposed to malaria but without S. mansoni infection can have hepatosplenomegaly, which even light S. mansoni infections can exacerbate in an intensity-dependent manner. Thus, concurrent chronic exposure to S. mansoni and Plasmodium falciparum can have an additive or synergistic effect on childhood morbidity. [ABSTRACT FROM AUTHOR]

Objective To explore patterns of water contact and Schistosoma mansoni exposure by age, sex, tribe and space within a single village. Methods For 10 months, we systematically observed water contacts made by the 800 inhabitants of a small Ugandan fishing village. In order to estimate cercarial exposure, times spent in water were weighted by snail infection levels, time of day and degree of immersion. Results There were marked differences in water contact patterns between the two main tribes, which inhabited geographically distinct ends of the village resulting in geographically distinct spatial patterns of water contact. The distributions of the intermediate hosts, Biomphalaria sudanica and Biomphalaria stanleyi, also appeared to differ over small distances. This led to quite different exposure patterns between the two tribes, particularly amongst females. Conclusions Schistosoma mansoni exposure can vary markedly within a single village. Such non-homogenous patterns of exposure are likely to have wider implications for schistosomiasis control programmes and research studies. [ABSTRACT FROM AUTHOR]

Cancer incidence and mortality in African countries is increasing, and chronic infections are playing the key role in the increase in malignancies. The vectors for malaria and schistosomiasis, as well as mycotoxins produced by fungi that contaminate food, are also causative factors. Other factors can increase the risk of cancer, such as exposure to pollutants in the workplace and environment. Atmospheric and indoor pollutants stemming from an increase in vehicular traffic, the use of biofuels, fumes from artisan workshops, industrial and agricultural pollution, and tobacco smoke are additional factors that could elevate the risk of cancer in Africa in the near future. It is becoming urgent to investigate these environmental factors and their impact on the oncogenesis process in order to develop cancer prevention policies and recommendations for the African continent. [ABSTRACT FROM AUTHOR]

We examined associations between schistosome-specific antibody responses and reinfection in Senegalese individuals recently exposed to Schistosoma mansoni. The effects of treatment, age, intensity of infection and duration of exposure on schistosome-specific antibody responses were also investigated by comparing immune responses in individuals exposed for less than 3 years with responses in people exposed for more than 8 years. All individuals were bled before treatment as well as 6 and 12 weeks after. We used a statistical model that included interaction terms between time, age, infection intensity and duration of exposure. The overall patterns of most specific antibody responses by age were similar to those previously published for S. mansoni, Schistosoma japonicum and Schistosoma haematobium infections in different endemic areas. In general, a boost in specific antibody responses against adult worm antigen (SWA) was observed at 6 weeks after treatment whereas the majority of isotype responses against egg antigen (SEA) were not affected by treatment. Our analysis showed that the effect of treatment on schistosome-specific antibody responses is influenced by age, infection intensity and duration of exposure. We found no evidence that treatment matures the specific antibody response of children recently infected with S. mansoni. Our results indicate that the build-up of potentially protective immunoglobulin E (IgE) responses was associated with duration of exposure, or, in other words, experience of infection. Interestingly, in recently exposed individuals there was a significant association between IgA responses to SWA and resistance to reinfection. Resistance to reinfection and production of IgA-SWA was associated with adulthood independently of exposure patterns, suggesting that susceptibility to S. mansoni and the development of protective immune responses is age-dependent. [ABSTRACT FROM AUTHOR]

Objective: To predict the spatial distributions of Schistosoma haematobium and S. mansoni infections to assist planning the implementation of mass distribution of praziquantel as part of an on-going national control programme in Tanzania.Methods: Bayesian geostatistical models were developed using parasitological data from 143 schools.Results: In the S. haematobium models, although land surface temperature and rainfall were significant predictors of prevalence, they became non-significant when spatial correlation was taken into account. In the S. mansoni models, distance to water bodies and annual minimum temperature were significant predictors, even when adjusting for spatial correlation. Spatial correlation occurred over greater distances for S. haematobium than for S. mansoni. Uncertainties in predictions were examined to identify areas requiring further data collection before programme implementation.Conclusion: Bayesian geostatistical analysis is a powerful and statistically robust tool for identifying high prevalence areas in a heterogeneous and imperfectly known environment. [ABSTRACT FROM AUTHOR]

Résumé: Malgré les grands progrès réalisés en matière de lutte contre la schistosomiase au cours de la dernière décennie sur tout le territoire du Burkina Faso, cette maladie demeure un problème de santé publique dans des régions où elle était auparavant endémique. En effet, cette étude a consisté en l’analyse de données parasitaires concernant Schistosoma haematobium et Schistosoma mansoni recueillies lors d’enquêtes parasitologiques et malacologiques. La présence de Schistosoma haematobium, avec des prévalences allant de 3,3 % à 50,4 %, a été confirmée, et celle de Schistosoma mansoni, avec des chiffres compris entre 3,3 % et 39,1 %, mais uniquement dans la partie ouest du Burkina Faso. Au niveau du sexe, les garçons sont plus infestés que les filles d’âge scolaire, mais le phénomène s’inverse chez les adultes, la femme étant plus infectée que l’homme. Sur le plan malacologique, Biomphalaria pfeifferi, Bulinus truncatus, Bulinus senegalensis et Bulinus globosus ont été mis en évidence au cours de cette étude. Les facteurs comportementaux, la dynamique et la répartition des hôtes intermédiaires jouent un rôle important dans la persistance de la maladie. [ABSTRACT FROM AUTHOR]

Résumé: Introduction. – La fièvre des safaris ou fièvre de primo-invasion bilharzienne, décrite initialement au Japon sous le nom de fièvre de Katayama, est une réaction immunoallergique toxémique liée à la présence dans les vaisseaux de l’organisme de cercaires infectantes. Nous rapportons le cas collectif de sept jeunes touristes en vacances au Mali. Exégèse. – Une jeune fille de 18 ans présente une fièvre céphalalgique au retour du pays Dogon (au sud du Mali). Après avoir éliminé un paludisme et devant la notion d’une baignade en eau douce suivie de prurit, une fièvre des safaris est évoquée et confirmée. L’alerte a alors été donnée auprès des autres membres du groupe. Ainsi tous ont pu être traités afin d’éviter le passage à la chronicité de cette bilharziose. Conclusion. – Cette observation rappelle que le risque bilharzien occasionné par une baignade en eau douce en zone d’endémie est une réalité. La prophylaxie repose sur l’éducation des voyageurs. La fièvre des safaris, lorsqu’elle survient, est un vrai signal d’alerte car correctement interprétée, permet d’éviter le passage vers une bilharziose chronique. [Copyright 2004 Elsevier]

Introduction: Schistosomiasis associated pulmonary arterial hypertension belongs to group 1 of the pulmonary hypertension classification and should be considered in any patient with pulmonary hypertension returning from an endemic area., Case Report: A 17-year-old patient was hospitalized for pulmonary hypertension detected during the initial assessment of viral hepatitis B-related cirrhosis with portal hypertension. The initial assessment established the diagnosis of pulmonary hypertension secondary to viral hepatitis B-cirrhosis. The patient's hepatic and haemodynamic condition deteriorated and he was treated with intravenous epoprostenol. This allowed subsequent performance of a liver transplantation. Epoprostenol could then be discontinued. Unexpectedly, histology of the liver explant revealed florid schistosomiasis in addition to hepatitis B cirrhosis., Conclusion: The diagnosis of pulmonary arterial hypertension associated with schistosomiasis may be difficult. It is necessary to repeat the serological studies and, sometimes, to obtain a rectal biopsy. The treatment of pulmonary arterial hypertension associated with schistosomiasis is based on specific therapies and antiparasitic treatment., (Copyright © 2018 SPLF. Published by Elsevier Masson SAS. All rights reserved.)