Imperial College London

Professor Alan Fenwick OBE

Faculty of MedicineSchool of Public Health

Emeritus Professor
 
 
 
//

Contact

 

+44 (0)20 7594 3418a.fenwick Website

 
 
//

Location

 

G30Norfolk PlaceSt Mary's Campus

//

Summary

 

Publications

Publication Type
Year
to

159 results found

Mutombo N, Landouré A, Man WY, Fenwick A, Dembélé R, Sacko M, Keita AD, Traoré MS, Webster JP, McLaws M-Let al., 2019, The association between child Schistosoma spp. infections and morbidity in an irrigated rice region in Mali: A localized study., Acta Trop, Vol: 199

BACKGROUND: Schistosomiasis is one of the neglected tropical diseases endemic to Mali. There has been insufficient investigation of the morbidity burden in highly endemic irrigated rice areas with the ongoing mass drug administration with praziquantel. In February 2005, a year after an initial mass drug administration in 2004, we performed the first cross-sectional survey of schistosomiasis in the Kokry-Bozo village in the Office du Niger rice irrigation region. In the fourteen years since this survey, there has been almost no research into schistosomiasis morbidity in Mali due to lack of funding. Therefore, the 2005 survey supplies near-baseline data for any future research into the treatment impacts in the area. METHODS: One hundred and ninety-four children aged 6-14 years from two schools were assessed for bladder pathology by ultrasound, and for anaemia and micro-haematuria by laboratory tests. Schistosoma eggs were examined microscopically in fresh stool and urine samples. Multivariate logistic regression analysis quantified the association of Schistosoma infections with anaemia, bladder pathology and micro-haematuria. Akaike's information criterion was used to test the assumption of linear effects of infection intensity classes and used to compare across models. RESULTS: The overall prevalence of schistosomiasis in 189 school children was 97%; 17% (33/189) had a single infection (S. mansoni,13%, or S. haematobium, 4%) and 80% (156/189) were co-infected with S. mansoni and S. haematobium. The overall prevalence of S. mansoni with light infection was 27% (53/194), moderate infection was 24% (47/194) and heavy infection was 42% (81/194). Of the 194 of children investigated for S. haematobium 59% (114/194) had light infection and 26% (50/194) had heavy infection. No hookworm eggs were detected. The level of abnormal bladder pathology was 18% (35/189) with the highest found in 10-14 year old children. The prevalence of anaemia was 91% (172/189) and was twice as lik

Journal article

Hotez PJ, Fenwick A, Molyneux DH, 2019, Collateral Benefits of Preventive Chemotherapy - Expanding the War on Neglected Tropical Diseases, NEW ENGLAND JOURNAL OF MEDICINE, Vol: 380, Pages: 2389-2391, ISSN: 0028-4793

Journal article

Ruberanziza E, Owada K, Clark NJ, Umulisa I, Ortu G, Lancaster W, Munyaneza T, Mbituyumuremyi A, Bayisenge U, Fenwick A, Soares Magalhães RJet al., 2019, Mapping Soil-Transmitted Helminth Parasite Infection in Rwanda: Estimating Endemicity and Identifying At-Risk Populations., Trop Med Infect Dis, Vol: 4

Soil-transmitted helminth (STH) infections are globally distributed intestinal parasite infections caused by Ascaris lumbricoides, Trichuris trichiura, and hookworms (Ancylostoma duodenale and Necator americanus). STH infection constitutes a major public health threat, with heavy burdens observed in many of the world's tropical and subtropical regions. Mass drug administration and sanitation improvements can drastically reduce STH prevalence and associated morbidity. However, identifying targeted areas in need of treatment is hampered by a lack of knowledge on geographical and population-level risk factors. In this study, we applied Bayesian geostatistical modelling to data from a national school-based STH infection survey in Rwanda to (1) identify ecological and population-level risk factors and (2) provide comprehensive precision maps of infection burdens. Our results indicated that STH infections were heterogeneously distributed across the country and showed signatures of spatial clustering, though the magnitude of clustering varied among parasites. The highest rates of endemic clustering were attributed to A. lumbricoides infection. Concordant infection patterns among the three parasite groups highlighted populations currently most at-risk of morbidity. Population-dense areas in the Western and North-Western regions of Rwanda represent areas that have continued to exhibit high STH burden across two surveys and are likely in need of targeted interventions. Our maps support the need for an updated evaluation of STH endemicity in western Rwanda to evaluate progress in MDA efforts and identify communities that need further local interventions to further reduce morbidity caused by STH infections.

Journal article

Hotez PJ, Harrison W, Fenwick A, Bustinduy AL, Ducker C, Mbabazi PS, Engels D, Kjetland EFet al., 2019, Female genital schistosomiasis and HIV/AIDS: Reversing the neglect of girls and women, PLOS NEGLECTED TROPICAL DISEASES, Vol: 13, ISSN: 1935-2735

Journal article

Hotez PJ, Biritwum N-K, Fenwick A, Molyneux DH, Sachs JDet al., 2019, Ghana: Accelerating neglected tropical disease control in a setting of economic development, PLOS NEGLECTED TROPICAL DISEASES, Vol: 13, ISSN: 1935-2735

Journal article

Fenwick A, 2019, Egypt's schistosomiasis control programme in the 1980s prepared the ground for the global elimination of schistosomiasis by 2030, TRANSACTIONS OF THE ROYAL SOCIETY OF TROPICAL MEDICINE AND HYGIENE, Vol: 113, Pages: 1-3, ISSN: 0035-9203

Journal article

Gazzinelli-Guimaraes PH, Dhanani N, King CH, Campbell CH, Aurelio HO, Ferro J, Nala R, Fenwick A, Phillips AEet al., 2018, Accuracy of the WHO praziquantel dose pole for large-scale community treatment of urogenital schistosomiasis in northern Mozambique: Is it time for an update?, PLOS NEGLECTED TROPICAL DISEASES, Vol: 12, ISSN: 1935-2735

Journal article

Jourdan PM, Lamberton PHL, Fenwick A, Addiss DGet al., 2018, Strongyloides stercoralis: the need for accurate information reply, LANCET, Vol: 391, Pages: 2323-2323, ISSN: 0140-6736

Journal article

Hotez PJ, Fenwick A, Ray SE, Hay SI, Molyneux DHet al., 2018, "Rapid impact" 10 years after: The first "decade" (2006-2016) of integrated neglected tropical disease control, PLOS NEGLECTED TROPICAL DISEASES, Vol: 12, ISSN: 1935-2735

Journal article

Clements MN, Corstjens PLAM, Binder S, Campbell CH, de Dood CJ, Fenwick A, Harrison W, Kayugi D, King CH, Kornelis D, Ndayishimiye O, Ortu G, Lamine MS, Zivieri A, Colley DG, van Dam GJet al., 2018, Latent class analysis to evaluate performance of point-of-care CCA for low-intensity Schistosoma mansoni infections in Burundi, Parasites & Vectors, Vol: 11, ISSN: 1756-3305

Background:Kato-Katz examination of stool smears is the field-standard method for detecting Schistosoma mansoni infection. However, Kato-Katz misses many active infections, especially of light intensity. Point-of-care circulating cathodic antigen (CCA) is an alternative field diagnostic that is more sensitive than Kato-Katz when intensity is low, but interpretation of CCA-trace results is unclear. To evaluate trace results, we tested urine and stool specimens from 398 pupils from eight schools in Burundi using four approaches: two in Burundi and two in a laboratory in Leiden, the Netherlands. In Burundi, we used Kato-Katz and point-of-care CCA (CCAB). In Leiden, we repeated the CCA (CCAL) and also used Up-Converting Phosphor Circulating Anodic Antigen (CAA).Methods:We applied Bayesian latent class analyses (LCA), first considering CCA traces as negative and then as positive. We used the LCA output to estimate validity of the prevalence estimates of each test in comparison to the population-level infection prevalence and estimated the proportion of trace results that were likely true positives.Results:Kato-Katz yielded the lowest prevalence (6.8%), and CCAB with trace considered positive yielded the highest (53.5%). There were many more trace results recorded by CCA in Burundi (32.4%) than in Leiden (2.3%). Estimated prevalence with CAA was 46.5%. LCA indicated that Kato-Katz had the lowest sensitivity: 15.9% [Bayesian Credible Interval (BCI): 9.2–23.5%] with CCA-trace considered negative and 15.0% with trace as positive (BCI: 9.6–21.4%), implying that Kato-Katz missed approximately 85% of infections. CCAB underestimated disease prevalence when trace was considered negative and overestimated disease prevalence when trace was considered positive, by approximately 12 percentage points each way, and CAA overestimated prevalence in both models. Our results suggest that approximately 52.2% (BCI: 37.8–5.8%) of the CCAB trace readings were true infections.

Journal article

Jourdan PM, Lamberton PHL, Fenwick A, Addiss DGet al., 2018, Soil-transmitted helminth infections, LANCET, Vol: 391, Pages: 252-265, ISSN: 0140-6736

Journal article

Phillips AE, Gazzinelli-Guimarães PH, Aurelio HO, Dhanani N, Ferro J, Nala R, Deol A, Fenwick Aet al., 2018, Urogenital schistosomiasis in Cabo Delgado, northern Mozambique: baseline findings from the SCORE study., Parasites & Vectors, Vol: 11, ISSN: 1756-3305

BACKGROUND: The results presented here are part of a five-year cluster-randomised intervention trial that was implemented to understand how best to gain and sustain control of schistosomiasis through different preventive chemotherapy strategies. This paper presents baseline data that were collected in ten districts of Cabo Delgado province, northern Mozambique, before treatment. METHODS: A cross-sectional study of 19,039 individuals was sampled from 144 villages from May to September 2011. In each village prevalence and intensity of S. haematobium were investigated in 100 children first-year students (aged 5-8 years), 100 school children aged 9-12 years (from classes 2 to 7) and 50 adults (20-55 years). Prevalence and intensity of S. haematobium infection were evaluated microscopically by two filtrations, each of 10 ml, from a single urine specimen. Given that individual and community perceptions of schistosomiasis influence control efforts, community knowledge and environmental risk factors were collected using a face-to-face interview. Data were entered onto mobile phones using EpiCollect. Data summary was made using descriptive statistics. Chi-square and logistic regression were used to determine the association between dependent and independent variables. RESULTS: The overall prevalence of urogenital schistosomiasis was 60.4% with an arithmetic mean intensity of infection of 55.8 eggs/10 ml of urine. Heavy infections were detected in 17.7%, of which 235 individuals (6.97%) had an egg count of 1000 eggs/10 ml or more. There was a significantly higher likelihood of males being infected than females across all ages (62% vs 58%; P < 0.0005). Adolescents aged 9-12 years had a higher prevalence (66.6%) and mean infection intensity (71.9 eggs/10 ml) than first-year students (63.1%; 58.2 eggs/10 ml). This is the first study in Mozambique looking at infection rates among adults. Although children had higher le

Journal article

Phillips AE, Gazzinelli-Guimaraes PH, Aurelio HO, Ferro J, Nala R, Clements M, King CH, Fenwick A, Fleming FM, Dhanani Net al., 2017, Assessing the benefits of five years of different approaches to treatment of urogenital schistosomiasis: A SCORE project in Northern Mozambique., PLoS Neglected Tropical Diseases, Vol: 11, ISSN: 1935-2727

BACKGROUND: In Mozambique, schistosomiasis is highly endemic across the whole country. The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) coordinates a five-year study that has been implemented in various African countries, including Mozambique. The overall goal of SCORE was to better understand how to best apply preventive chemotherapy with praziquantel (PZQ) for schistosomiasis control by evaluating the impact of alternative treatment approaches. METHODS: This was a cluster-randomised trial that compared the impact of different treatment strategies in study areas with prevalence among school children of ≥21% S. haematobium infection by urine dipstick. Each village was randomly allocated to one of six possible combinations of community-wide treatment (CWT), school-based treatment (SBT), and/or drug holidays over a period of four years, followed by final data collection in the fifth year. The most intense intervention arm involved four years of CWT, while the least intensive arm involved two years of SBT followed by two consecutive years of PZQ holiday. Each study arm included 25 villages randomly assigned to one of the six treatment arms. The primary outcome of interest was change in prevalence and intensity of S. haematobium among 100 children aged 9-to-12-years that were sampled each year in every village. In addition to children aged 9-to-12 years, 100 children aged 5-8 years in their first-year of school and 50 adults (aged 20-55 years) were tested in the first and final fifth year of the study. Prevalence and intensity of S. haematobium infection was evaluated by two filtrations, each of 10mL, from a single urine specimen. PRINCIPAL FINDINGS: In total, data was collected from 81,167 individuals across 149 villages in ten districts of Cabo Delgado province, Northern Mozambique. Overall PZQ treatment resulted in a significant reduction in the prevalence of S. haematobium infection from Year 1 to Year 5, where the average prevalence

Journal article

Clements MN, Donnelly CA, Fenwick A, Kabatereine NB, Knowles SCI, Meité A, N'Goran EK, Nalule Y, Nogaro S, Phillips AE, Tukahebwa EM, Fleming FMet al., 2017, Interpreting ambiguous 'trace' results in Schistosoma mansoni CCA tests: estimating sensitivity and specificity of ambiguous results with no gold standard, PLoS Neglected Tropical Diseases, Vol: 11, ISSN: 1935-2727

BackgroundThe development of new diagnostics is an important tool in the fight against disease. Latent Class Analysis (LCA) is used to estimate the sensitivity and specificity of tests in the absence of a gold standard. The main field diagnostic for Schistosoma mansoni infection, Kato-Katz (KK), is not very sensitive at low infection intensities. A point-of-care circulating cathodic antigen (CCA) test has been shown to be more sensitive than KK. However, CCA can return an ambiguous ‘trace’ result between ‘positive’ and ‘negative’, and much debate has focused on interpretation of traces results.Methodology/Principle findingsWe show how LCA can be extended to include ambiguous trace results and analyse S. mansoni studies from both Côte d’Ivoire (CdI) and Uganda. We compare the diagnostic performance of KK and CCA and the observed results by each test to the estimated infection prevalence in the population.Prevalence by KK was higher in CdI (13.4%) than in Uganda (6.1%), but prevalence by CCA was similar between countries, both when trace was assumed to be negative (CCAtn: 11.7% in CdI and 9.7% in Uganda) and positive (CCAtp: 20.1% in CdI and 22.5% in Uganda). The estimated sensitivity of CCA was more consistent between countries than the estimated sensitivity of KK, and estimated infection prevalence did not significantly differ between CdI (20.5%) and Uganda (19.1%). The prevalence by CCA with trace as positive did not differ significantly from estimates of infection prevalence in either country, whereas both KK and CCA with trace as negative significantly underestimated infection prevalence in both countries.ConclusionsIncorporation of ambiguous results into an LCA enables the effect of different treatment thresholds to be directly assessed and is applicable in many fields. Our results showed that CCA with trace as positive most accurately estimated infection prevalence.

Journal article

Chami GF, Kontoleon AA, Bulte E, Fenwick A, Kabatereine NB, Tukahebwa EM, Dunne DWet al., 2017, Diffusion of treatment in social networks and mass drug administration., Nature Communications, Vol: 8, ISSN: 2041-1723

Information, behaviors, and technologies spread when people interact. Understanding these interactions is critical for achieving the greatest diffusion of public interventions. Yet, little is known about the performance of starting points (seed nodes) for diffusion. We track routine mass drug administration-the large-scale distribution of deworming drugs-in Uganda. We observe friendship networks, socioeconomic factors, and treatment delivery outcomes for 16,357 individuals in 3491 households of 17 rural villages. Each village has two community medicine distributors (CMDs), who are the seed nodes and responsible for administering treatments. Here, we show that CMDs with tightly knit (clustered) friendship connections achieve the greatest reach and speed of treatment coverage. Importantly, we demonstrate that clustering predicts diffusion through social networks when spreading relies on contact with seed nodes while centrality is unrelated to diffusion. Clustering should be considered when selecting seed nodes for large-scale treatment campaigns.

Journal article

Assoum M, Ortu G, Basanez M-G, Lau C, Clements ACA, Halton K, Fenwick A, Magalhaes RJSet al., 2017, Spatiotemporal distribution and population at risk of soil-transmitted helminth infections following an eight-year school-based deworming programme in Burundi, 2007-2014, Parasites & Vectors, Vol: 10, ISSN: 1756-3305

Background: Investigating the effect of successive annual deworming rounds on the spatiotemporal distribution ofinfection prevalence and numbers at risk for soil-transmitted helminths (STHs) can help identify communitiesnearing elimination and those needing further interventions. In this study, we aim to quantify the impact ofan 8-year mass drug administration (MDA) programme (from 2007 to 2014) on the spatiotemporal distribution ofprevalence of STH infections and to estimate the number of school-aged children infected with STHs in Burundi.Methods: During annual longitudinal school-based surveys in Burundi between 2007 and 2011, STH infection andanthropometric data for a total of 40,656 children were collected; these data were supplemented with data froma national survey conducted in 2014. Bayesian model based geostatistics (MBG) were used to generate predictiveprevalence maps for each STH species and year. The numbers of children at-risk of infection per district between2008 and 2014 were estimated as the product of the predictive prevalence maps and population density maps.Results: Overall, the degree of spatial clustering of STH infections decreased between 2008 and 2011; in 2014 thegeographical clusters of all STH infections reappeared. The reduction in prevalence was small for Ascaris lumbricoidesand Trichuris trichiura in the centre and central north of the country. Our predictive prevalence maps for hookwormindicate a reduction in prevalence along the periphery of the country. The predicted number of children infected withany STH species decreased substantially between 2007 and 2011, but in 2014 there was an increase in the predictednumber of children infected with A. lumbricoides and T. trichiura. In 2014, the districts with the highest predictednumber of children infected with A. lumbricoides, T. trichiura and hookworms were Kibuye district (n = 128,903),Mabayi district (n = 35,302) and Kiremba (n = 87,511), respectively.Conclusions: While the MDA programme

Journal article

Shen Y, King CH, Binder S, Zhang F, Whalen CC, Secor WE, Montgomery SP, Mwinzi PNM, Olsen A, Magnussen P, Kinung'hi S, Phillips AE, Nala R, Ferro J, Aurelio HO, Fleming F, Garba A, Hamidou A, Fenwick A, Campbell CH, Colley DGet al., 2017, Protocol and baseline data for a multi-year cohort study of the effects of different mass drug treatment approaches on functional morbidities from schistosomiasis in four African countries, BMC INFECTIOUS DISEASES, Vol: 17

Journal article

Knowles SCL, Sturrock HJW, Turner H, Whitton JM, Gower CM, Jemu S, Phillips AE, Meite A, Thomas B, Kollie K, Thomas C, Rebollo MP, Styles B, Clements M, Fenwick A, Harrison WE, Fleming FMet al., 2017, Optimising cluster survey design for planning schistosomiasis preventive chemotherapy, PLOS Neglected Tropical Diseases, Vol: 11, ISSN: 1935-2735

BackgroundThe cornerstone of current schistosomiasis control programmes is delivery of praziquantel to at-risk populations. Such preventive chemotherapy requires accurate information on the geographic distribution of infection, yet the performance of alternative survey designs for estimating prevalence and converting this into treatment decisions has not been thoroughly evaluated.Methodology/Principal findingsWe used baseline schistosomiasis mapping surveys from three countries (Malawi, Côte d’Ivoire and Liberia) to generate spatially realistic gold standard datasets, against which we tested alternative two-stage cluster survey designs. We assessed how sampling different numbers of schools per district (2–20) and children per school (10–50) influences the accuracy of prevalence estimates and treatment class assignment, and we compared survey cost-efficiency using data from Malawi. Due to the focal nature of schistosomiasis, up to 53% simulated surveys involving 2–5 schools per district failed to detect schistosomiasis in low endemicity areas (1–10% prevalence). Increasing the number of schools surveyed per district improved treatment class assignment far more than increasing the number of children sampled per school. For Malawi, surveys of 15 schools per district and 20–30 children per school reliably detected endemic schistosomiasis and maximised cost-efficiency. In sensitivity analyses where treatment costs and the country considered were varied, optimal survey size was remarkably consistent, with cost-efficiency maximised at 15–20 schools per district.Conclusions/SignificanceAmong two-stage cluster surveys for schistosomiasis, our simulations indicated that surveying 15–20 schools per district and 20–30 children per school optimised cost-efficiency and minimised the risk of under-treatment, with surveys involving more schools of greater cost-efficiency as treatment costs rose.

Journal article

Fenwick A, 2017, Schistosomiasis research and control since the retirement of Sir Patrick Manson in 1914, TRANSACTIONS OF THE ROYAL SOCIETY OF TROPICAL MEDICINE AND HYGIENE, Vol: 111, Pages: 191-198, ISSN: 0035-9203

Journal article

Chami GF, Kontoleon AA, Bulte E, Fenwick A, Kabatereine NB, Tukahebwa EM, Dunne DWet al., 2017, Community-directed mass drug administration is undermined by status seeking in friendship networks and inadequate trust in health advice networks, SOCIAL SCIENCE & MEDICINE, Vol: 183, Pages: 37-47, ISSN: 0277-9536

Over 1.9 billion individuals require preventive chemotherapy through mass drug administration (MDA). Community-directed MDA relies on volunteer community medicine distributors (CMDs) and their achievement of high coverage and compliance. Yet, it is unknown if village social networks influence effective MDA implementation by CMDs. In Mayuge District, Uganda, census-style surveys were conducted for 16,357 individuals from 3,491 households in 17 villages. Praziquantel, albendazole, and ivermectin were administered for one month in community-directed MDA to treat Schistosoma mansoni, hookworm, and lymphatic filariasis. Self-reported treatment outcomes, socioeconomic characteristics, friendship networks, and health advice networks were collected. We investigated systematically missed coverage and noncompliance. Coverage was defined as an eligible person being offered at least one drug by CMDs; compliance included ingesting at least one of the offered drugs. These outcomes were analyzed as a two-stage process using a Heckman selection model. To further assess if MDA through CMDs was working as intended, we examined the probability of accurate drug administration of 1) praziquantel, 2) both albendazole and ivermectin, and 3) all drugs. This analysis was conducted using bivariate Probit regression. Four indicators from each social network were examined: degree, betweenness centrality, closeness centrality, and the presence of a direct connection to CMDs. All models accounted for nested household and village standard errors. CMDs were more likely to offer medicines, and to accurately administer the drugs as trained by the national control programme, to individuals with high friendship degree (many connections) and high friendship closeness centrality (households that were only a short number of steps away from all other households in the network). Though high (88.59%), additional compliance was associated with directly trusting CMDs for health advice. Effective treatment pro

Journal article

Savioli L, Albonico M, Colley DG, Correa-Oliveira R, Fenwick A, Green W, Kabatereine N, Kabore A, Katz N, Klohe K, Loverde PT, Rollinson D, Stothard JR, Tchuente L-AT, Waltz J, Zhou X-Net al., 2017, Building a global schistosomiasis alliance: an opportunity to join forces to fight inequality and rural poverty, INFECTIOUS DISEASES OF POVERTY, Vol: 6, ISSN: 2049-9957

Journal article

Ortu G, Ndayishimiye O, Clements M, Kayugi D, Campbell CH, Lamine MS, Zivieri A, Magalhaes RS, Binder S, King CH, Fenwick A, Colley DG, Jourdan PMet al., 2017, Countrywide reassessment of Schistosoma mansoni infection in Burundi using a urine-circulating cathodic antigen rapid test: informing the national control program., American Journal of Tropical Medicine and Hygiene, Vol: 96, Pages: 664-673, ISSN: 1476-1645

Following implementation of the national control program, a reassessment of Schistosoma mansoni prevalence was conducted in Burundi to determine the feasibility of moving toward elimination. A countrywide cluster-randomized cross-sectional study was performed in May 2014. At least 25 schools were sampled from each of five eco-epidemiological risk zones for schistosomiasis. Fifty randomly selected children 13-14 years of age per school were included for a single urine-circulating cathodic antigen (CCA) rapid test and, in a subset of schools, for duplicate Kato-Katz slides preparation from a single stool sample. A total of 17,331 children from 347 schools were tested using CCA. The overall prevalence of S. mansoni infection, when CCA trace results were considered negative, was 13.5% (zone range [zr] = 4.6-17.8%), and when CCA trace results were considered positive, it was 42.8% (zr = 34.3-49.9%). In 170 schools, prevalence of this infection determined using Kato-Katz method was 1.5% (zr ==0-2.7%). The overall mean intensity of S. mansoni infection determined using Kato-Katz was 0.85 eggs per gram (standard deviation = 10.86). A majority of schools (84%) were classified as non-endemic (prevalence = 0) using Kato-Katz; however, a similar proportion of schools were classified as endemic when CCA trace results were considered negative (85%) and nearly all (98%) were endemic when CCA trace results were considered positive. The findings of this nationwide reassessment using CCA rapid test indicate that Schistosoma infection is still widespread in Burundi, although its average intensity is probably low. Further evidence is now needed to determine the association between CCA rapid test positivity and low-intensity disease transmission.

Journal article

Phillips AE, Gazzinelli-Guinmaraes P, Aurelio O, Ferro J, Nala R, Dhanani N, Fenwick Aet al., 2017, IMPACT OF DIFFERENT TREATMENT STRATEGIES OVER FIVE YEARS FOR SCHISTOSOMIASIS IN MOZAMBIQUE, 66th Annual Meeting of the American-Society-of-Tropical-Medicine-and-Hygiene (ASTMH), Publisher: AMER SOC TROP MED & HYGIENE, Pages: 33-33, ISSN: 0002-9637

Conference paper

Mutapi F, Maizels R, Fenwick A, Woolhouse Met al., 2016, Human schistosomiasis in the post mass drug administration era, LANCET INFECTIOUS DISEASES, Vol: 17, Pages: E42-E48, ISSN: 1473-3099

Journal article

Lo NC, Addiss DG, Hotez PJ, King CH, Stothard JR, Evans DS, Colley DG, Lin W, Coulibaly JT, Bustinduy AL, Raso G, Bendavid E, Bogoch II, Fenwick A, Savioli L, Molyneux D, Utzinger J, Andrews JRet al., 2016, A call to strengthen the global strategy against schistosomiasis and soil-transmitted helminthiasis: the time is now, LANCET INFECTIOUS DISEASES, Vol: 17, Pages: E64-E69, ISSN: 1473-3099

Journal article

Ortu G, Assoum M, Wittmann U, Knowles S, Clements M, Ndayishimiye O, Basáñez MG, Lau C, Clements A, Fenwick A, Magalhaes RJet al., 2016, The impact of an 8-year mass drug administration programme on prevalence, intensity and co-infections of soil-transmitted helminthiases in Burundi, Parasites & Vectors, Vol: 9, Pages: 513-513, ISSN: 1756-3305

BACKGROUND: Soil-transmitted helminth (STH) infections are amongst the most prevalent infections in the world. Mass drug administration (MDA) programmes have become the most commonly used national interventions for endemic countries to achieve elimination. This paper aims to describe the effect of an 8-year MDA programme on the prevalence, intensity of infection and co-infection of STH in Burundi from 2007 to 2014 and critically appraise the trajectory towards STH elimination in the country. RESULTS: Annual STH parasitological surveys (specifically, a "pilot study" from 2007 to 2011, an "extension study" from 2008 to 2011, and a "national reassessment" in 2014; n = 27,658 children), showed a significant drop in prevalence of infection with any STH ("pooled STH") between baseline and 2011 in both studies, falling from 32 to 16 % in the pilot study, and from 35 to 16 % in the extension study. Most STH infections were of low intensity according to WHO classification. The national reassessment in 2014 showed that prevalence of pooled STH remained significantly below the prevalence in 2007 in both studies but there was no further decrease in STH prevalence from 2011 levels during this time. Spatial dependence analysis showed that prevalence of Trichuris trichiura and Ascaris lumbricoides had a tendency to cluster over the years, whilst only trends in spatial dependence were evident for hookworm infections. Spatial dependence fluctuated over the course of the programme for Ascaris lumbricoides and Trichuris trichiura. However, spatial trends in spatial dependence were evident in 2010 for Ascaris lumbricoides. Analysis of spatial clustering of intensity of infection and heavy infections revealed that the intensity changed over time for all parasites. Heavy intensity was only evident in Ascaris lumbricoides for 2008 and did not appear in proceeding years and other parasites. CONCLUSIONS: These results demonstra

Journal article

Robinson O, Toledano MB, Sands C, Beckonert O, Want EJ, Goldin R, Hauser ML, Fenwick A, Thursz MR, Coen Met al., 2016, Global metabolic changes induced by plant-derived pyrrolizidine alkaloids following a human poisoning outbreak and in a mouse model, Toxicology Research, Vol: 5, Pages: 1594-1603, ISSN: 2045-4538

Several hundred cases of Hirmi Valley Liver Disease (HVLD), an often fatal liver injury, occurred from 2001 to 2011 in a cluster of rural villages in Tigray, Ethiopia. HVLD is principally caused by contamination of the food supply with plant derived pyrrolizidine alkaloids (PAs), with high exposure to the pesticide DDT among villagers increasing their susceptibility. In an untargeted global approach we aimed to identify metabolic changes induced by PA exposure through 1H NMR spectroscopic based metabolic profiling. We analysed spectra acquired from urine collected from HVLD cases and controls and a murine model of PA exposure and PA/DDT co-exposure, using multivariate partial least squares discriminant analysis. In the human models we identified changes in urinary concentrations of tyrosine, pyruvate, bile acids, N-acetylglycoproteins, N-methylnicotinamide and formate, hippurate, p-cresol sulphate, p-hydroxybenzoate and 3-(3-hydroxyphenyl) propionic acid. Tyrosine and p-cresol sulphate were associated with both exposure and disease. Similar changes to tyrosine, one-carbon intermediates and microbial associated metabolites were observed in the mouse model, with tyrosine correlated with the extent of liver damage. These results provide mechanistic insight and implicate the gut microflora in the human response to challenge with toxins. Pathways identified here may be useful in translational research and as “exposome” signals.

Journal article

Ezeamama AE, He C-L, Shen Y, Yin X-P, Binder SC, Campbell CH, Rathbun S, Whalen CC, N'Goran EK, Utzinger J, Olsen A, Magnussen P, Kinung'hi S, Fenwick A, Phillips A, Ferro J, Karanja DMS, Mwinzi PNM, Montgomery S, Secor WE, Hamidou A, Garba A, King CH, Colley DGet al., 2016, Gaining and sustaining schistosomiasis control: study protocol and baseline data prior to different treatment strategies in five African countries, BMC Infectious Diseases, Vol: 16, ISSN: 1471-2334

BackgroundThe Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) was established in 2008 to answer strategic questions about schistosomiasis control. For programme managers, a high-priority question is: what are the most cost-effective strategies for delivering preventive chemotherapy (PCT) with praziquantel (PZQ)? This paper describes the process SCORE used to transform this question into a harmonized research protocol, the study design for answering this question, the village eligibility assessments and data resulting from the first year of the study.MethodsBeginning in 2009, SCORE held a series of meetings to specify empirical questions and design studies related to different schedules of PCT for schistosomiasis control in communities with high (gaining control studies) and moderate (sustaining control studies) prevalence of Schistosoma infection among school-aged children. Seven studies are currently being implemented in five African countries. During the first year, villages were screened for eligibility, and data were collected on prevalence and intensity of infection prior to randomisation and the implementation of different schemes of PZQ intervention strategies.ResultsThese studies of different treatment schedules with PZQ will provide the most comprehensive data thus far on the optimal frequency and continuity of PCT for schistosomiasis infection and morbidity control.ConclusionsWe expect that the study outcomes will provide data for decision-making for country programme managers and a rich resource of information to the schistosomiasis research community.

Journal article

Fenwick A, Jourdan P, 2016, Schistosomiasis elimination by 2020 or 2030?, International Journal for Parasitology, Vol: 46, Pages: 385-388, ISSN: 1879-0135

Schistosomiasis has been a public health burden in a number of countries across the globe for centuries and probably beyond. The World Health Organization and partners are currently preparing to move towards elimination of this disease. However, given the historical challenges and barriers to ridding areas of this water-borne parasite infection, we question whether the current targets for eliminating schistosomiasis as a global health problem can be achieved.

Journal article

Knopp S, Person B, Ame SM, Ali SM, Muhsin J, Juma S, Khamis IS, Rabone M, Blair L, Fenwick A, Mohammed KA, Rollinson Det al., 2016, Praziquantel coverage in schools and communities targeted for the elimination of urogenital schistosomiasis in Zanzibar: a cross-sectional survey, Parasites & Vectors, Vol: 9, ISSN: 1756-3305

BACKGROUND: Biannual mass drug administration (MDA) with praziquantel and additional interventions to eliminate urogenital schistosomiasis has been implemented on the Zanzibar islands, United Republic of Tanzania, since 2012. We aimed to assess the coverage of school-based treatment (SBT) and community-wide treatment (CWT), to validate the coverage reported by the Zanzibar Ministry of Health (MoH) and to identify reasons for non-compliance. METHODS: We conducted a post-MDA cross-sectional survey in 93 schools and 92 communities on Pemba and Unguja islands in early 2014, 3-5 months after the last MDA round. Pupils and adults were asked whether they had received and taken the praziquantel treatment provided in the last SBT or CWT, respectively, and the observed and reported coverage were compared. Reasons for non-compliance were recorded in a pretested questionnaire and assessed in qualitative interviews. Urine samples of participants were examined for Schistosoma haematobium eggs with a single urine filtration. RESULTS: Around 8000 pupils and 4000 adults were included in the analysis. Our survey revealed a SBT coverage of 85.2% in Pemba and of 86.9% in Unguja, which was in line with MoH reports from Pemba (84.3%) and higher than reports from Unguja (63.9%). However, 15 among the 48 schools surveyed in Unguja had not received SBT. Among the interviewed adults, 53.6% in Pemba and 64.9% in Unguja had received praziquantel during CWT, which was less than the 59.0% and 67.7%, respectively, indicated by MoH reports. Moreover, only 43.8% and 54.0% of adults in Pemba and Unguja, respectively, had taken all the tablets as recommended. The main reasons for not receiving or taking praziquantel were absence during CWT, no drug distributor coming, being busy, fear of adverse events, pregnancy, breastfeeding or feeling healthy. CONCLUSION: To increase coverage and compliance in Zanzibar, SBT should target all schools and mobilization, sensitization and implementation of the CWT ne

Journal article

This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.

Request URL: http://wlsprd.imperial.ac.uk:80/respub/WEB-INF/jsp/search-html.jsp Request URI: /respub/WEB-INF/jsp/search-html.jsp Query String: respub-action=search.html&id=00366086&limit=30&person=true