The Experts below are selected from a list of 40536 Experts worldwide ranked by ideXlab platform
Russell J Stothard - One of the best experts on this subject based on the ideXlab platform.
-
precision mapping an innovative tool and way forward to shrink the map better target interventions and accelerate toward the elimination of Schistosomiasis
PLOS Neglected Tropical Diseases, 2018Co-Authors: Louisalbert Tchuem Tchuente, David Rollinson, Russell J Stothard, Jutta ReinhardruppAbstract:The mainstay of current Schistosomiasis control is preventive chemotherapy (PC) with praziquantel, targeted toward school-aged children, based on the disease endemicity within a subset of surveyed schools, which are classified using parasitological prevalence and intensity of infections [1]. However, it is well known that the current conventional mapping design for Schistosomiasis has shown several limitations and may lead to several uncertainties and misclassification of some districts and their eligibility for PC. These inaccuracies prevent successful PC coverage of all populations that need treatment and, therefore, jeopardise the achievement of Schistosomiasis elimination [2]. Our recent studies have revealed that precision mapping of Schistosomiasis is an essential requirement to move from disease control toward interruption of schistosome transmission in sub-Saharan Africa. As Schistosomiasis is a focal disease geographically, having a high-resolution map is necessary if current or future interventions are to be targeted accordingly. Precision mapping is defined as conducting sampling at a much finer geographical resolution, potentially examining all schools within every subunit in each implementation unit in order to eliminate the errors caused by missing the focal variation in Schistosomiasis prevalence. Indeed, current mapping protocols and sampling frames perform badly when assessing this landscape
-
female genital Schistosomiasis fgs from case reports to a call for concerted action against this neglected gynaecological disease
International Journal for Parasitology, 2016Co-Authors: Vanessa Christinet, Russell J Stothard, Janis K Lazdinshelds, Jutta ReinhardruppAbstract:In recent years, control of neglected tropical diseases has been increasingly gaining momentum and interventions against Schistosomiasis are being progressively scaled-up through expansion of donated praziquantel and preventive chemotherapy campaigns. However, the public health importance of female genital Schistosomiasis is not fully recognised nor its control is adequately addressed. Taking a clinical and anatomopathological perspective, we evaluated the available literature to highlight the importance of female genital Schistosomiasis and its connections with two sexually transmitted infections of global importance, Human Immunodeficiency Virus (HIV) and Human Papilloma Virus. Outside the long list of clinical descriptive reports beginning in 1899, there is presently a shocking gap in epidemiological assessment and a significant underestimation of the burden of FGS remains. The scarcity of integrated approaches to address female genital Schistosomiasis calls for more concerted action in its detection, treatment and prevention alongside other concomitant women's health issues, otherwise female genital Schistosomiasis will remain a neglected gynaecological disease.
-
Schistosomiasis in pre school age children and their mothers in chikhwawa district malawi with notes on characterization of schistosomes and snails
Parasites & Vectors, 2014Co-Authors: Helen Poole, Dianne J Terlouw, Andrew Naunje, Kondwani Mzembe, Michelle C Stanton, Martha Betson, David G Lalloo, Russell J StothardAbstract:To complement ongoing Schistosomiasis control within national control programmes (NCPs) that administer praziquantel to school-age children, assessing the risk and extent of Schistosomiasis in pre-school-age children (PSAC) is important. In June 2012, Schistosomiasis in Chikhwawa district, Malawi was assessed across 12 villages examining pre-school-age children (PSAC) and their mothers by serological and parasitological diagnosis, as supplemented with urine-antigen and questionnaire-interview methods. Urinary tract morbidity was inferred by haematuria and albuminuria assays. In total, 49.5% (CI95 42.6-56.4) of 208 PSAC and 94.5% (CI95 90.9-98.1) of 165 mothers were seropositive for Schistosomiasis, in 2 villages seroprevalence exceeded 75% in PSAC. Egg-patent urogenital and intestinal Schistosomiasis was observed; 17.7% (CI95 12.4-23.2) of PSAC and 45.1% (CI95 37.4-52.8) of mothers having active Schistosomiasis by parasitological and urine-antigen testing combined. PSAC often had extensive daily water contact and many (~25%) had haematuria and albuminuria. As eggs with an atypical morphology of Schistosoma haematobium were observed, a general selection of schistosome eggs was characterized by DNA barcoding, finding Group I S. haematobium and Group IV and V S. mansoni. Malacological surveys encountered several populations of Bulinus globosus but failed to find Biomphalaria. Both PSAC and their mothers appear to be at significant risk of Schistosomiasis and should be considered for treatment within the NCP of Malawi.
Janelisa Musaya - One of the best experts on this subject based on the ideXlab platform.
-
an outbreak of intestinal Schistosomiasis alongside increasing urogenital Schistosomiasis prevalence in primary school children on the shoreline of lake malawi mangochi district malawi
Infectious Diseases of Poverty, 2020Co-Authors: Sekeleghe Kayuni, Angus M Oferrall, Hamish Baxter, Josie Hesketh, Bright Mainga, David Lally, Mohammad H Alharbi, James E Lacourse, Lazarus Juziwelo, Janelisa MusayaAbstract:Intestinal Schistosomiasis was not considered endemic in Lake Malawi until November 2017 when populations of Biomphalaria pfeifferi were first reported; in May 2018, emergence of intestinal Schistosomiasis was confirmed. This emergence was in spite of ongoing control of urogenital Schistosomiasis by preventive chemotherapy. Our current study sought to ascertain whether intestinal Schistosomiasis is transitioning from emergence to outbreak, to judge if stepped-up control interventions are needed. During late-May 2019, three cross-sectional surveys of primary school children for Schistosomiasis were conducted using a combination of rapid diagnostic tests, parasitological examinations and applied morbidity-markers; 1) Schistosomiasis dynamics were assessed at Samama (n = 80) and Mchoka (n = 80) schools, where Schistosoma mansoni was first reported, 2) occurrence of S. mansoni was investigated at two non-sampled schools, Mangochi Orphan Education and Training (MOET) (n = 60) and Koche (n = 60) schools, where B. pfeifferi was nearby, and 3) rapid mapping of Schistosomiasis, and B. pfeifferi, conducted across a further 8 shoreline schools (n = 240). After data collection, univariate analyses and Chi-square testing were performed, followed by binary logistic regression using generalized linear models, to investigate epidemiological associations. In total, 520 children from 12 lakeshore primary schools were examined, mean prevalence of S. mansoni by ‘positive’ urine circulating cathodic antigen (CCA)-dipsticks was 31.5% (95% confidence interval [CI]: 27.5–35.5). Upon comparisons of infection prevalence in May 2018, significant increases at Samama (relative risk [RR] = 1.7, 95% CI: 1.4–2.2) and Mchoka (RR = 2.7, 95% CI: 1.7–4.3) schools were observed. Intestinal Schistosomiasis was confirmed at MOET (18.3%) and Koche (35.0%) schools, and in all rapid mapping schools, ranging from 10.0 to 56.7%. Several populations of B. pfeifferi were confirmed, with two new eastern shoreline locations noted. Mean prevalence of urogenital Schistosomiasis was 24.0% (95% CI: 20.3–27.7). We notify that intestinal Schistosomiasis, once considered non-endemic in Lake Malawi, is now transitioning from emergence to outbreak. Once control interventions can resume after coronavirus disease 2019 (COVID-19) suspensions, we recommend stepped-up preventive chemotherapy, with increased community-access to treatments, alongside renewed efforts in appropriate environmental control.
Geoffrey N Gobert - One of the best experts on this subject based on the ideXlab platform.
-
droplet digital pcr diagnosis of human Schistosomiasis parasite cell free dna detection in diverse clinical samples
The Journal of Infectious Diseases, 2017Co-Authors: Geoffrey N Gobert, Remigio M. Olveda, Gail M Williams, Kosala Weerakoon, Catherine A Gordon, Pengfei Cai, Allen G RossAbstract:Schistosomiasis japonica remains a major public health and socio-economic concern in Southeast-Asia. Sensitive and accurate diagnostics can play a pivotal role in achieving disease elimination goals. We previously reported a novel droplet digital-PCR (ddPCR) assay targeting the mitochondrial gene nad1 to diagnose Schistosomiasis japonica. The tool identified both pre-patent and patent infections using Schistosoma japonicum DNA isolated from serum, urine, salivary glands and faeces in a murine model. The assay was validated here using clinical samples collected from 412 subjects resident in an area moderately endemic for Schistosomiasis in the Philippines. S. japonicum DNA present in human stool, serum, urine and saliva was detected quantitatively with high sensitivity. The capability to diagnose cases of human Schistosomiasis using non-invasively collected clinical samples, the higher level of sensitivity obtained compared with the microscopy-based Kato-Katz test, and the capacity to quantify infection intensity, have important public health implications for Schistosomiasis control and programs targeting other neglected tropical diseases. This verified ddPCR method represents a valuable new tool for the diagnosis and surveillance of Schistosomiasis, particularly in low prevalence and low intensity areas approaching elimination and in monitoring areas where disease emergence or re-emergence is a concern.
-
transcriptional profiling of chronic clinical hepatic Schistosomiasis japonica indicates reduced metabolism and immune responses
Parasitology, 2015Co-Authors: Geoffrey N Gobert, Melissa L Burke, Magda K Ellis, Donald P Mcmanus, Candy Chuah, Grant A Ramm, Yuanyuan WangAbstract:Schistosomiasis is a significant cause of human morbidity and mortality. We performed a genome-wide transcriptional survey of liver biopsies obtained from Chinese patients with chronic Schistosomiasis only, or chronic Schistosomiasis with a current or past history of viral hepatitis B. Both disease groups were compared with patients with no prior history or indicators of any liver disease. Analysis showed in the main, downregulation in gene expression, particularly those involved in signal transduction via EIF2 signalling and mTOR signalling, as were genes associated with cellular remodelling. Focusing on immune associated pathways, genes were generally downregulated. However, a set of three genes associated with granulocytes, MMP7, CLDN7, CXCL6 were upregulated. Differential gene profiles unique to Schistosomiasis included the gene Granulin which was decreased despite being generally considered a marker for liver disease, and IGBP2 which is associated with increased liver size, and was the most upregulated gene in Schistosomiasis only patients, all of which presented with hepatomegaly. The unique features of gene expression, in conjunction with previous reports in the murine model of the cellular composition of granulomas, granuloma formation and recovery, provide an increased understanding of the molecular immunopathology and general physiological processes underlying hepatic Schistosomiasis.
-
real time pcr demonstrates high prevalence of schistosoma japonicum in the philippines implications for surveillance and control
PLOS Neglected Tropical Diseases, 2015Co-Authors: Catherine A Gordon, Geoffrey N Gobert, Remigio M. Olveda, Allen G Ross, Donald A Harn, Darren J Gray, Gail M Williams, Luz P Acosta, Donald P McmanusAbstract:The Philippines has a population of approximately 103 million people, of which 6.7 million live in Schistosomiasis-endemic areas with 1.8 million people being at risk of infection with Schistosoma japonicum. Although the country-wide prevalence of Schistosomiasis japonica in the Philippines is relatively low, the prevalence of Schistosomiasis can be high, approaching 65% in some endemic areas. Of the currently available microscopy-based diagnostic techniques for detecting schistosome infections in the Philippines and elsewhere, most exhibit varying diagnostic performances, with the Kato-Katz (KK) method having particularly poor sensitivity for detecting low intensity infections. This suggests that the actual prevalence of Schistosomiasis japonica may be much higher than previous reports have indicated. Six barangay (villages) were selected to determine the prevalence of S. japonicum in humans in the municipality of Palapag, Northern Samar. Fecal samples were collected from 560 humans and examined by the KK method and a validated real-time PCR (qPCR) assay. A high S. japonicum prevalence (90.2%) was revealed using qPCR whereas the KK method indicated a lower prevalence (22.9%). The geometric mean eggs per gram (GMEPG) determined by the qPCR was 36.5 and 11.5 by the KK. These results, particularly those obtained by the qPCR, indicate that the prevalence of Schistosomiasis in this region of the Philippines is much higher than historically reported. Despite being more expensive, qPCR can complement the KK procedure, particularly for surveillance and monitoring of areas where extensive Schistosomiasis control has led to low prevalence and intensity infections and where Schistosomiasis elimination is on the horizon, as for example in southern China.
-
immunopathogenesis of human Schistosomiasis
Parasite Immunology, 2009Co-Authors: Melissa L Burke, Malcolm K Jones, Geoffrey N Gobert, Magda K Ellis, Donald P McmanusAbstract:Schistosomiasis continues to be a significant cause of parasitic morbidity and mortality worldwide. This review considers the basic features of the pathology and clinical outcomes of hepatointestinal and genitourinary Schistosomiasis, presents an overview of the numerous studies on animal models that have clarified many of the immunopathological features, and provides insight into our current understanding of the immunopathogenesis and genetic control of human Schistosomiasis. In murine Schistosomiasis, pathology is induced by a CD4(+) Th2 driven granulomatous response directed against schistosome eggs lodged in the host liver. The Th2 cytokines IL-4 and IL-13 drive this response, whereas IL-10, IL13Ralpha2, IFN-gamma and a subset of regulatory T-cells act to limit schistosome induced pathology. A variety of cell types including hepatic stellate cells, alternatively activated macrophages and regulatory T-cells have also been implicated in the pathogenesis of Schistosomiasis. Current knowledge suggests the immunopathogenic mechanisms underlying human Schistosomiasis are likely to be similar. The review also considers the future development of anti-pathology schistosome vaccines. As fibrosis is an important feature of many other diseases such as Crohn's disease and sarcoidosis, a comprehensive understanding of the cellular and molecular mechanisms involved in Schistosomiasis may also ultimately contribute to the development an effective disease intervention strategy for other granulofibrotic diseases.
Kosala Weerakoon - One of the best experts on this subject based on the ideXlab platform.
-
droplet digital pcr diagnosis of human Schistosomiasis parasite cell free dna detection in diverse clinical samples
The Journal of Infectious Diseases, 2017Co-Authors: Geoffrey N Gobert, Remigio M. Olveda, Gail M Williams, Kosala Weerakoon, Catherine A Gordon, Pengfei Cai, Allen G RossAbstract:Schistosomiasis japonica remains a major public health and socio-economic concern in Southeast-Asia. Sensitive and accurate diagnostics can play a pivotal role in achieving disease elimination goals. We previously reported a novel droplet digital-PCR (ddPCR) assay targeting the mitochondrial gene nad1 to diagnose Schistosomiasis japonica. The tool identified both pre-patent and patent infections using Schistosoma japonicum DNA isolated from serum, urine, salivary glands and faeces in a murine model. The assay was validated here using clinical samples collected from 412 subjects resident in an area moderately endemic for Schistosomiasis in the Philippines. S. japonicum DNA present in human stool, serum, urine and saliva was detected quantitatively with high sensitivity. The capability to diagnose cases of human Schistosomiasis using non-invasively collected clinical samples, the higher level of sensitivity obtained compared with the microscopy-based Kato-Katz test, and the capacity to quantify infection intensity, have important public health implications for Schistosomiasis control and programs targeting other neglected tropical diseases. This verified ddPCR method represents a valuable new tool for the diagnosis and surveillance of Schistosomiasis, particularly in low prevalence and low intensity areas approaching elimination and in monitoring areas where disease emergence or re-emergence is a concern.
Langui Song - One of the best experts on this subject based on the ideXlab platform.
-
a cross sectional survey comparing a free treatment program for advanced Schistosomiasis japonica to a general assistance program
Parasitology Research, 2017Co-Authors: Langui Song, Beibei Zhang, Jiahua Liu, An NingAbstract:The prevalence and intensity of Schistosomiasis has dropped dramatically in China due to an effective integrated control program. However, advanced Schistosomiasis is becoming a key challenge on the road to elimination. The aims of this study were to compare the disease condition between advanced cases under the general assistance program (GAP) and free treatment program (FTP) and to determine whether the FTP should be popularized to provide an objective reference for policymakers in China's advanced Schistosomiasis control program. One hundred and ninety-four patients with Schistosomiasis japonica who were enrolled in the GAP or FTP participated in this study. Little significant difference was observed in the potential confounders, including general characteristics, comorbidities, and lifestyle, indicating a similar effect on the pathology of liver damage caused by schistosome infection. There was no apparent difference in the incidence of common clinical symptoms. Furthermore, no significant difference was observed in the ultrasound findings, implying that the GAP and FTP groups shared a similar degree of liver lesion. With the exception of the abnormal rates of aspartate aminotransferase (AST), alkaline phosphatase (ALP), and hyaluronic acid (HA), the other serological indicators were comparable between the groups. Overall, the FTP is not a better option for controlling advanced Schistosomiasis in China. It is important to reveal the precise mechanism underlying the pathogenesis of advanced Schistosomiasis so that specific approaches to treating and preventing the development of advanced Schistosomiasis can be developed and Schistosomiasis can be eliminated in China.
-
lessons from a 15 year old boy with advanced Schistosomiasis japonica in china a case report
Parasitology Research, 2017Co-Authors: Langui Song, An NingAbstract:Schistosomiasis is a chronic, parasitic disease caused by flukes (trematodes) of the genus Schistosoma, which presents the most important global burden of the 17 neglected tropical diseases listed by the World Health Organization. China has made great achievements in Schistosomiasis control, and now China is planning to move forward, to eliminate Schistosomiasis within 2020, but the fact cannot be denied that the possibility of schistosome infection is still there in some endemic due to its zoonotic nature as well as wide distribution of its intermediate hosts (snails). Thus, how to interrupt the transmission in areas with distribution of schistosomes and intermediate snails becomes a very serious challenge that China is facing. In this paper, it is reported an advanced Schistosomiasis japonica case of a 15-year-old boy which is extremely rare in the current Schistosomiasis control in China. Thus, it is supposed to strengthen health education of school children and to train professional physicians of local hospitals.
