The Experts below are selected from a list of 1749 Experts worldwide ranked by ideXlab platform
Annette Olsen - One of the best experts on this subject based on the ideXlab platform.
-
Prevalence of lymphatic filariasis, malaria and soil transmitted Helminthiasis in a community of Bardiya District, western Nepal
Southeast Asian Journal of Tropical Medicine and Public Health, 2014Co-Authors: Samir Ranjitkar, Annette Olsen, Michael Alifrangis, Madhav Adhikari, Paul E. Simonsen, Dan W. MeyrowitschAbstract:Lymphatic filariasis (LF), malaria and soil transmitted Helminthiasis (STH) cause major health problems in Nepal, but in spite of this very few stud- ies have been carried out on these parasitic infections in Nepal. A cross sectional survey of all three categories of parasitic infections was carried out in Deuda- kala Village of Bardiya District, western Nepal. A total of 510 individuals aged 5 years and above were examined from finger prick blood for circulating filarial antigen (CFA), malaria antigen using a rapid diagnostic test (RDT), and malaria DNA using a PCR-based assay. In addition, 317 individuals were examined for Soil-Transmitted helminth (STH) eggs by the Kato-Katz technique. Prevalence of LF, malaria (antigen) and STH infection was 25.1%, 0.6% and 18.3%, respectively. PCR analysis did not detect any additional malaria cases. The prevalence of LF and STH infections differ significantly among different age groups and ethnic communities. The high prevalence of LF in the community studied indicates an immediate need for implementing a mass drug administration program for its control in this particular geographical area of Nepal.
-
The acceptability and safety of praziquantel alone and in combination with mebendazole in the treatment of Schistosoma mansoni and Soil-Transmitted Helminthiasis in children aged 1–4 years in Uganda
Parasitology, 2011Co-Authors: Harriet Namwanje, Narcis B. Kabatereine, Annette OlsenAbstract:There is limited information on the acceptability and safety of praziquantel for treatment of schistosomiasis in children below the age of four years. In addition, although mebendazole has been extensively used together with praziquantel against infections with schistosomiasis and Soil-Transmitted Helminthiasis (STH) in school-aged children, no specific acceptability or safety studies have been published on this drug combination in younger children. A randomized clinical trial was conducted to determine the safety of praziquantel alone and in combination with mebendazole in the treatment of Schistosoma mansoni and STH in children aged 1 to 4 years. A total of 596 children from Bwondha fishing community in Mayuge district and Wang-Kado fishing community in Nebbi district were investigated using duplicate Kato-Katz thick smears of two stool samples and 130 (21·8%) were found infected with S. mansoni. Of these, 19·2% (25) had heavy intensity of infections. Of the infected children, 82 were included and randomised into praziquantel (40 mg/kg) + mebendazole (500 mg) or praziquantel (40 mg/kg) alone. Many symptoms were reported before treatment while very few were reported after treatment and all on treatment day. No serious adverse events were reported or observed after treatment. Praziquantel with or without mebendazole was well tolerated in small children in the study area.
-
Can coverage of schistosomiasis and soil transmitted Helminthiasis control programmes targeting school-aged children be improved ? New approaches
Parasitology, 2009Co-Authors: K. Massa, A. Sheshe, R. Ntakamulenga, B. Ndawi, Annette Olsen, Pascal MagnussenAbstract:Control programmes generally use a school-based strategy of mass drug administration to reduce morbidity of schistosomiasis and Soil-Transmitted Helminthiasis (STH) in school-aged populations. The success of school-based programmes depends on treatment coverage. The community-directed treatment (ComDT) approach has been implemented in the control of onchocerciasis and lymphatic filariasis in Africa and improves treatment coverage. This study compared the treatment coverage between the ComDT approach and the school-based treatment approach, where non-enrolled school-aged children were invited for treatment, in the control of schistosomiasis and STH among enrolled and non-enrolled school-aged children. Coverage during the first treatment round among enrolled children was similar for the two approaches (ComDT: 80·3% versus school: 82·1 %, P=0·072). However, for the non-enrolled children the ComDT approach achieved a significantly higher coverage than the school-based approach (80·0 versus 59·2%, P
-
The combined effect of the Lymphatic Filariasis Elimination Programme and the Schistosomiasis and Soil-Transmitted Helminthiasis Control Programme on Soil-Transmitted Helminthiasis in schoolchildren in Tanzania.
Transactions of The Royal Society of Tropical Medicine and Hygiene, 2008Co-Authors: K. Massa, Pascal Magnussen, A. Sheshe, R. Ntakamulenga, B. Ndawi, Annette OlsenAbstract:The combined effect of the Lymphatic Filariasis Elimination Programme (LFEP) and the National Schistosomiasis and Soil-Transmitted Helminthiasis Control Programme (NSSCP) on Soil-Transmitted Helminthiasis (STH) was evaluated. In September 2004, before mass drug administration (MDA) with ivermectin and albendazole by the LFEP in October, the prevalence and intensity of STH were recorded in 228 pupils in one primary school. After 8 months, all available pupils were re-examined, and the prevalence of Ascaris lumbricoides, Trichuris trichiura and hookworm had decreased from 0.9 to 0.7% (P = 0.84), from 4.8 to 0.7% (P = 0.004) and from 45.6 to 11.9% (P
-
The effect of the community-directed treatment approach versus the school-based treatment approach on the prevalence and intensity of schistosomiasis and Soil-Transmitted Helminthiasis among schoolchildren in Tanzania.
Transactions of The Royal Society of Tropical Medicine and Hygiene, 2008Co-Authors: K. Massa, Pascal Magnussen, A. Sheshe, R. Ntakamulenga, B. Ndawi, Annette OlsenAbstract:This study compared the effect of the community-directed treatment (ComDT) approach and the school-based treatment approach on the prevalence and intensity of schistosomiasis and Soil-Transmitted Helminthiasis (STH) among schoolchildren. Following a parasitological survey in a randomly selected sample of 1140 schoolchildren school-age children in 10 study villages received one dose of praziquantel (40 mg/kg body weight) against schistosomiasis and one dose of albendazole (400mg) against STH. Five of these villages implemented the ComDT approach and received treatment by community drug distributors while school teachers administered treatment in five other villages using the school-based approach. At 12 months follow-up the prevalence of Schistosoma mansoni and Trichuris trichiura infections were similar between the ComDT and the school-based approaches when examined in randomly selected schoolchildren (10.1 vs. 9.4% P=0.66 and 0.8 vs. 1.4% P=0.37). However the prevalence of S. haematobium and hookworm infections were significantly lower in the ComDT approach villages compared to the school-based approach villages (10.6 vs. 16.3% P=0.005 and 2.9 vs. 5.8% P=0.01 respectively). The results showed that the ComDT approach is at least as effective as the school-based approach in reducing prevalence and intensity of schistosomiasis and STH among schoolchildren.
Antonio Montresor - One of the best experts on this subject based on the ideXlab platform.
-
Provision of deworming intervention to pregnant women by antenatal services in countries endemic for Soil-Transmitted Helminthiasis
PLOS Neglected Tropical Diseases, 2019Co-Authors: Mathieu Bangert, Pilar Bancalari, Denise Mupfasoni, Alexei Mikhailov, Albis Francesco Gabrielli, Antonio MontresorAbstract:Background The World Health Organization has recently reemphasized the importance of providing preventive chemotherapy to women of reproductive age in countries endemic for Soil-Transmitted Helminthiasis as they are at heightened risk of associated morbidity. The Demographic and Health Surveys (DHS) Program is responsible for collecting and disseminating accurate, nationally representative data on health and population in developing countries. Our study aims to estimate the number of pregnant women at risk of Soil-Transmitted Helminthiasis that self-reported deworming by antenatal services in endemic countries that conducted Demographic and Health Surveys. Methodology/Principal findings The number of pregnant women living in endemic countries was extrapolated from the United Nations World Population Prospects 2015. National deworming coverage among pregnant women were extracted from Demographic and Health Surveys and applied to total numbers of pregnant women in the country. Sub-national DHS with data on self-reported deworming were available from 49 of the 102 endemic countries. In some regions more than 73% of STH endemic countries had a DHS. The DHS report an average deworming coverage of 23% (CI 19–28), ranging from 2% (CI 1–3) to 35% (CI 29–40) in the different regions, meaning more than 16 million pregnant women were dewormed in countries surveyed by DHS. The deworming rates amongst the 43 million pregnant women in STH endemic countries not surveyed by DHS remains unknown. Conclusions/Significance These estimates will serve to establish baseline numbers of deworming coverage among pregnant women, monitor progress, and urge endemic countries to continue working toward reducing the burden of Soil-Transmitted Helminthiasis. The DHS program should be extended to STH-endemic countries currently not covering the topic of deworming during pregnancy.
-
Preventive chemotherapy to control Soil-Transmitted Helminthiasis averted more than 500 000 DALYs in 2015
Transactions of The Royal Society of Tropical Medicine and Hygiene, 2017Co-Authors: Antonio Montresor, Mathieu Bangert, Denise Mupfasoni, Alexei Mikhailov, William Trouleau, Serene A. Joseph, Christopher FitzpatrickAbstract:Preventive chemotherapy (PC), the large-scale administration of anthelminthics, is recommended by the World Health Organization (WHO) for the control of Soil-Transmitted Helminthiasis (STH). Since 2010, donated anthelminthics for STH have boosted the implementation of PC programmes in children, achieving global coverage of more than 60% in 2015. The WHO Global Health Estimates attribute an annual loss of over 3.3 million disability-adjusted life-years (DALYs) to STH. The aim of this study is to estimate the impact of PC programmes on child morbidity. We used data from the WHO Global Health Estimates, national coverage data on PC and the results of an evaluation of the impact of PC in 17 countries on morbidity previously conducted by our group. We estimated that the implementation of PC averted in 2015 over 44% of the DALYs that would have been caused in children by STH without the control intervention. A reduction in morbidity of over 75% is expected, if the global target is reached in 2020. If the programme is subsequently maintained, morbidity from STH will be almost totally removed by 2025. In endemic areas, preventive chemotherapy provides a significant health benefit. We consider this estimation potentially useful to evaluate the cost utility of the investment made by several endemic countries on PC to control STH. © The Author(s) 2018. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
-
Preventive chemotherapy for schistosomiasis and Soil-Transmitted Helminthiasis by cotreatment with praziquantel and albendazole
Clinical investigation, 2014Co-Authors: J. Russell Stothard, Amaya L. Bustinduy, Antonio MontresorAbstract:In disease-endemic areas, preventive chemotherapy with two orally administered anthelminthic drugs, praziquantel and albendazole, forms the foundation of control of schistosomiasis and Soil-Transmitted Helminthiasis. Where diseases overlap, these two drugs are typically co-administered simultaneously, although albendazole is often interchangeable with mebendazole. With a supportive pharmaceutical industry that donates drugs and a strong international partnership that mobilizes donor funds for drug delivery, scale-up of treatment in school-aged children has expanded significantly in line with the WHO 2012–2020 strategic plan. Other high-risk groups, such as pre-school-aged children, are now benefiting from deworming campaigns conducted alongside other childhood interventions, such as vaccination, less so, however, for schistosomiasis as infections in this age class are not being treated. Looking to the future, maintaining an effective drug distribution and reporting system that regularly checks anthelminth...
-
Cure rate is not a valid indicator for assessing drug efficacy and impact of preventive chemotherapy interventions against schistosomiasis and Soil-Transmitted Helminthiasis
Transactions of The Royal Society of Tropical Medicine and Hygiene, 2011Co-Authors: Antonio MontresorAbstract:Every year in endemic countries, several million individuals are given anthelminthic drugs in the context of preventive chemotherapy programmes for morbidity control of schistosomiasis and Soil-Transmitted Helminthiasis. The capacity to evaluate accurately the efficacy of the drugs used as well as the health impact produced by treatment is of utmost importance for appropriate planning and implementation of these interventions. Cure rate is an indicator of drug efficacy that was originally developed for assessing the clinical efficacy of antibiotics on selected bacterial diseases. Over time, this indicator has also been widely applied to anthelminthic drugs and consequently used to monitor and evaluate preventive chemotherapy interventions. In the author's opinion, however, measurement of cure rate provides information of limited usefulness in the context of helminth control programmes. The present article analyses the peculiarities of helminth infections and those of the drugs used in preventive chemotherapy, explaining the reasons why the cure rate is not an adequate indicator in this specific public health context.
-
Moderate and high endemicity of schistosomiasis is a predictor of the endemicity of Soil-Transmitted Helminthiasis: a systematic review
Transactions of The Royal Society of Tropical Medicine and Hygiene, 2011Co-Authors: Aya Yajima, Albis Francesco Gabrielli, Antonio Montresor, Dirk EngelsAbstract:Abstract The authors conducted a systematic literature review with the following aims: to investigate how frequently Soil-Transmitted Helminthiasis (STH) infections are endemic where schistosomiasis is present; and to assess the correlation between the risk level of schistosomiasis and that of STH. Among 155 sites on which data were collected and analyzed, schistosomiasis was present in 130, all of which were also co-endemic for STH, whereas 25 sites were endemic only for STH. Ninety percent (117 out of 130) of the areas eligible for preventive chemotherapy (PC) against schistosomiasis are also eligible for PC against STH. This fact provides managers of control programmes with the operationally important indication that use of available information on endemicity of schistosomiasis is a valid tool to predict the presence of STH in the same geographical area and to estimate the need of PC for STH. The implementation of this tool is expected to save financial and human resources and help accelerate the scale-up of PC throughout the world.
K. Massa - One of the best experts on this subject based on the ideXlab platform.
-
Can coverage of schistosomiasis and soil transmitted Helminthiasis control programmes targeting school-aged children be improved ? New approaches
Parasitology, 2009Co-Authors: K. Massa, A. Sheshe, R. Ntakamulenga, B. Ndawi, Annette Olsen, Pascal MagnussenAbstract:Control programmes generally use a school-based strategy of mass drug administration to reduce morbidity of schistosomiasis and Soil-Transmitted Helminthiasis (STH) in school-aged populations. The success of school-based programmes depends on treatment coverage. The community-directed treatment (ComDT) approach has been implemented in the control of onchocerciasis and lymphatic filariasis in Africa and improves treatment coverage. This study compared the treatment coverage between the ComDT approach and the school-based treatment approach, where non-enrolled school-aged children were invited for treatment, in the control of schistosomiasis and STH among enrolled and non-enrolled school-aged children. Coverage during the first treatment round among enrolled children was similar for the two approaches (ComDT: 80·3% versus school: 82·1 %, P=0·072). However, for the non-enrolled children the ComDT approach achieved a significantly higher coverage than the school-based approach (80·0 versus 59·2%, P
-
The combined effect of the Lymphatic Filariasis Elimination Programme and the Schistosomiasis and Soil-Transmitted Helminthiasis Control Programme on Soil-Transmitted Helminthiasis in schoolchildren in Tanzania.
Transactions of The Royal Society of Tropical Medicine and Hygiene, 2008Co-Authors: K. Massa, Pascal Magnussen, A. Sheshe, R. Ntakamulenga, B. Ndawi, Annette OlsenAbstract:The combined effect of the Lymphatic Filariasis Elimination Programme (LFEP) and the National Schistosomiasis and Soil-Transmitted Helminthiasis Control Programme (NSSCP) on Soil-Transmitted Helminthiasis (STH) was evaluated. In September 2004, before mass drug administration (MDA) with ivermectin and albendazole by the LFEP in October, the prevalence and intensity of STH were recorded in 228 pupils in one primary school. After 8 months, all available pupils were re-examined, and the prevalence of Ascaris lumbricoides, Trichuris trichiura and hookworm had decreased from 0.9 to 0.7% (P = 0.84), from 4.8 to 0.7% (P = 0.004) and from 45.6 to 11.9% (P
-
The effect of the community-directed treatment approach versus the school-based treatment approach on the prevalence and intensity of schistosomiasis and Soil-Transmitted Helminthiasis among schoolchildren in Tanzania.
Transactions of The Royal Society of Tropical Medicine and Hygiene, 2008Co-Authors: K. Massa, Pascal Magnussen, A. Sheshe, R. Ntakamulenga, B. Ndawi, Annette OlsenAbstract:This study compared the effect of the community-directed treatment (ComDT) approach and the school-based treatment approach on the prevalence and intensity of schistosomiasis and Soil-Transmitted Helminthiasis (STH) among schoolchildren. Following a parasitological survey in a randomly selected sample of 1140 schoolchildren school-age children in 10 study villages received one dose of praziquantel (40 mg/kg body weight) against schistosomiasis and one dose of albendazole (400mg) against STH. Five of these villages implemented the ComDT approach and received treatment by community drug distributors while school teachers administered treatment in five other villages using the school-based approach. At 12 months follow-up the prevalence of Schistosoma mansoni and Trichuris trichiura infections were similar between the ComDT and the school-based approaches when examined in randomly selected schoolchildren (10.1 vs. 9.4% P=0.66 and 0.8 vs. 1.4% P=0.37). However the prevalence of S. haematobium and hookworm infections were significantly lower in the ComDT approach villages compared to the school-based approach villages (10.6 vs. 16.3% P=0.005 and 2.9 vs. 5.8% P=0.01 respectively). The results showed that the ComDT approach is at least as effective as the school-based approach in reducing prevalence and intensity of schistosomiasis and STH among schoolchildren.
-
Community perceptions on the community-directed treatment and school-based approaches for the control of schistosomiasis and Soil-Transmitted Helminthiasis among school-age children in lushoto district, tanzania
Journal of Biosocial Science, 2008Co-Authors: K. Massa, Pascal Magnussen, A. Sheshe, R. Ntakamulenga, B. Ndawi, Annette OlsenAbstract:The success of the Community-Directed Treatment (ComDT) approach in the control of onchocerciasis and filariasis has caught the attention of other disease control programmes. In this study the ComDT approach was implemented and compared with the school-based approach for control of schistosomiasis and Soil-Transmitted Helminthiasis among school-age children in Lushoto District, Tanzania. This was a qualitative study, consisting of in-depth interviews with village leaders, community drug distributors (CDDs) and schoolteachers, as well as focus group discussions with separate groups of mothers and fathers to assess the perceptions and experiences of the villagers on the implementation of the two approaches. It was found that the villagers accepted the ComDT approach and took the responsibility of selecting the CDDs, organizing and implementing their own method of distributing drugs to the school-age children in their villages. The ComDT approach was well received and was successfully implemented in the villages. Although the villagers pointed out the limitation in reaching the non-enrolled children in the school-based approach, they also expressed satisfaction with this approach. This study suggests that the ComDT approach is well accepted and can be implemented effectively to ensure better coverage of especially non-enrolled school-age children.
Pascal Magnussen - One of the best experts on this subject based on the ideXlab platform.
-
Can coverage of schistosomiasis and soil transmitted Helminthiasis control programmes targeting school-aged children be improved ? New approaches
Parasitology, 2009Co-Authors: K. Massa, A. Sheshe, R. Ntakamulenga, B. Ndawi, Annette Olsen, Pascal MagnussenAbstract:Control programmes generally use a school-based strategy of mass drug administration to reduce morbidity of schistosomiasis and Soil-Transmitted Helminthiasis (STH) in school-aged populations. The success of school-based programmes depends on treatment coverage. The community-directed treatment (ComDT) approach has been implemented in the control of onchocerciasis and lymphatic filariasis in Africa and improves treatment coverage. This study compared the treatment coverage between the ComDT approach and the school-based treatment approach, where non-enrolled school-aged children were invited for treatment, in the control of schistosomiasis and STH among enrolled and non-enrolled school-aged children. Coverage during the first treatment round among enrolled children was similar for the two approaches (ComDT: 80·3% versus school: 82·1 %, P=0·072). However, for the non-enrolled children the ComDT approach achieved a significantly higher coverage than the school-based approach (80·0 versus 59·2%, P
-
The combined effect of the Lymphatic Filariasis Elimination Programme and the Schistosomiasis and Soil-Transmitted Helminthiasis Control Programme on Soil-Transmitted Helminthiasis in schoolchildren in Tanzania.
Transactions of The Royal Society of Tropical Medicine and Hygiene, 2008Co-Authors: K. Massa, Pascal Magnussen, A. Sheshe, R. Ntakamulenga, B. Ndawi, Annette OlsenAbstract:The combined effect of the Lymphatic Filariasis Elimination Programme (LFEP) and the National Schistosomiasis and Soil-Transmitted Helminthiasis Control Programme (NSSCP) on Soil-Transmitted Helminthiasis (STH) was evaluated. In September 2004, before mass drug administration (MDA) with ivermectin and albendazole by the LFEP in October, the prevalence and intensity of STH were recorded in 228 pupils in one primary school. After 8 months, all available pupils were re-examined, and the prevalence of Ascaris lumbricoides, Trichuris trichiura and hookworm had decreased from 0.9 to 0.7% (P = 0.84), from 4.8 to 0.7% (P = 0.004) and from 45.6 to 11.9% (P
-
The effect of the community-directed treatment approach versus the school-based treatment approach on the prevalence and intensity of schistosomiasis and Soil-Transmitted Helminthiasis among schoolchildren in Tanzania.
Transactions of The Royal Society of Tropical Medicine and Hygiene, 2008Co-Authors: K. Massa, Pascal Magnussen, A. Sheshe, R. Ntakamulenga, B. Ndawi, Annette OlsenAbstract:This study compared the effect of the community-directed treatment (ComDT) approach and the school-based treatment approach on the prevalence and intensity of schistosomiasis and Soil-Transmitted Helminthiasis (STH) among schoolchildren. Following a parasitological survey in a randomly selected sample of 1140 schoolchildren school-age children in 10 study villages received one dose of praziquantel (40 mg/kg body weight) against schistosomiasis and one dose of albendazole (400mg) against STH. Five of these villages implemented the ComDT approach and received treatment by community drug distributors while school teachers administered treatment in five other villages using the school-based approach. At 12 months follow-up the prevalence of Schistosoma mansoni and Trichuris trichiura infections were similar between the ComDT and the school-based approaches when examined in randomly selected schoolchildren (10.1 vs. 9.4% P=0.66 and 0.8 vs. 1.4% P=0.37). However the prevalence of S. haematobium and hookworm infections were significantly lower in the ComDT approach villages compared to the school-based approach villages (10.6 vs. 16.3% P=0.005 and 2.9 vs. 5.8% P=0.01 respectively). The results showed that the ComDT approach is at least as effective as the school-based approach in reducing prevalence and intensity of schistosomiasis and STH among schoolchildren.
-
Community perceptions on the community-directed treatment and school-based approaches for the control of schistosomiasis and Soil-Transmitted Helminthiasis among school-age children in lushoto district, tanzania
Journal of Biosocial Science, 2008Co-Authors: K. Massa, Pascal Magnussen, A. Sheshe, R. Ntakamulenga, B. Ndawi, Annette OlsenAbstract:The success of the Community-Directed Treatment (ComDT) approach in the control of onchocerciasis and filariasis has caught the attention of other disease control programmes. In this study the ComDT approach was implemented and compared with the school-based approach for control of schistosomiasis and Soil-Transmitted Helminthiasis among school-age children in Lushoto District, Tanzania. This was a qualitative study, consisting of in-depth interviews with village leaders, community drug distributors (CDDs) and schoolteachers, as well as focus group discussions with separate groups of mothers and fathers to assess the perceptions and experiences of the villagers on the implementation of the two approaches. It was found that the villagers accepted the ComDT approach and took the responsibility of selecting the CDDs, organizing and implementing their own method of distributing drugs to the school-age children in their villages. The ComDT approach was well received and was successfully implemented in the villages. Although the villagers pointed out the limitation in reaching the non-enrolled children in the school-based approach, they also expressed satisfaction with this approach. This study suggests that the ComDT approach is well accepted and can be implemented effectively to ensure better coverage of especially non-enrolled school-age children.
Jürg Utzinger - One of the best experts on this subject based on the ideXlab platform.
-
Shrinking risk profiles after deworming of children in Port Elizabeth, South Africa, with special reference to Ascaris lumbricoides and Trichuris trichiura
Geospatial Health, 2017Co-Authors: Ivan Müller, Peter Steinmann, Stefanie Gall, Lindsey Beyleveld, Markus Gerber, Uwe Pühse, Rosa Du Randt, Leyli Zondie, Cheryl Walter, Jürg UtzingerAbstract:Risk maps facilitate discussion among different stakeholders and provide a tool for spatial targeting of health interventions. We present maps documenting shrinking risk profiles after deworming with respect to Soil-Transmitted Helminthiasis among schoolchildren from disadvantaged neighbourhoods in Port Elizabeth, South Africa. Children were examined for Soil-Transmitted helminth infections using duplicate Kato-Katz thick smears in March 2015, October 2015 and May 2016, and subsequently treated with albendazole after each survey. The mean infection intensities for Ascaris lumbricoides were 9,554 eggs per gram of stool (EPG) in March 2015, 4,317 EPG in October 2015 and 1,684 EPG in March 2016. The corresponding figures for Trichuris trichiura were 664 EPG, 331 EPG and 87 EPG. Repeated deworming shrank the risk of Soil-Transmitted Helminthiasis, but should be complemented by other public health measures.
-
Assessment of global guidelines for preventive chemotherapy against schistosomiasis and Soil-Transmitted Helminthiasis: a cost-effectiveness modelling study
Lancet Infectious Diseases, 2016Co-Authors: Nathan C. Lo, Jean T. Coulibaly, Dimitrios-alexios Karagiannis-voules, Isaac I. Bogoch, Eran Bendavid, Jürg Utzinger, Penelope Vounatsou, Jason R. AndrewsAbstract:Summary Background WHO guidelines recommend annual treatment for schistosomiasis or Soil-Transmitted Helminthiasis when prevalence in school-aged children is at or above a threshold of 50% and 20%, respectively. Separate treatment guidelines are used for these two helminthiases, and integrated community-wide treatment is not recommended. We assessed the cost-effectiveness of changing prevalence thresholds and treatment guidelines under an integrated delivery framework. Methods We developed a dynamic, age-structured transmission and cost-effectiveness model that simulates integrated preventive chemotherapy programmes against schistosomiasis and Soil-Transmitted Helminthiasis. We assessed a 5-year treatment programme with praziquantel (40 mg/kg per treatment) against schistosomiasis and albendazole (400 mg per treatment) against Soil-Transmitted Helminthiasis at 75% coverage. We defined strategies as highly cost-effective if the incremental cost-effectiveness ratio was less than the World Bank classification for a low-income country (gross domestic product of US$1045 per capita). We calculated the prevalence thresholds for cost-effective preventive chemotherapy of various strategies, and estimated treatment needs for sub-Saharan Africa. Findings Annual preventive chemotherapy against schistosomiasis was highly cost-effective in treatment of school-aged children at a prevalence threshold of 5% (95% uncertainty interval [UI] 1·7–5·2; current guidelines recommend treatment at 50% prevalence) and for community-wide treatment at a prevalence of 15% (7·3–18·5; current recommendation is unclear, some community treatment recommended at 50% prevalence). Annual preventive chemotherapy against Soil-Transmitted Helminthiasis was highly cost-effective in treatment of school-aged children at a prevalence of 20% (95% UI 5·4–30·5; current guidelines recommend treatment at 20% prevalence) and the entire community at 60% (35·3–85·1; no guidelines available). When both helminthiases were co-endemic, prevalence thresholds using integrated delivery were lower. Using this revised treatment framework, we estimated that treatment needs would be six times higher than WHO guidelines for praziquantel and two times higher for albendazole. An additional 21·3% (95% Bayesian credible interval 20·4–22·2) of the population changed from receiving non-integrated treatment under WHO guidelines to integrated treatment (both praziquantel and albendazole). Country-specific economic differences resulted in heterogeneity around these prevalence thresholds. Interpretation Annual preventive chemotherapy programmes against schistosomiasis and Soil-Transmitted Helminthiasis are likely to be highly cost-effective at prevalences lower than WHO recommendations. These findings support substantial treatment scale-up, community-wide coverage, integrated treatment in co-endemic settings that yield substantial cost synergies, and country-specific treatment guidelines. Funding Doris Duke Charitable Foundation, Mount Sinai Hospital-University Health Network AMO Innovation Fund, and Stanford University Medical Scholars Programme.
-
Comparison of community-wide, integrated mass drug administration strategies for schistosomiasis and Soil-Transmitted Helminthiasis: a cost-effectiveness modelling study
The Lancet Global Health, 2015Co-Authors: Nathan C. Lo, Jean T. Coulibaly, Isaac I. Bogoch, Jürg Utzinger, Eliézer K. N'goran, Brian G. Blackburn, Giovanna Raso, Sören L. Becker, Howard Abrams, Jason R. AndrewsAbstract:Summary Background More than 1·5 billion people are affected by schistosomiasis or Soil-Transmitted Helminthiasis. WHO's recommendations for mass drug administration (MDA) against these parasitic infections emphasise treatment of school-aged children, using separate treatment guidelines for these two helminthiases groups. We aimed to evaluate the cost-effectiveness of expanding integrated MDA to the entire community in four settings in Cote d'Ivoire. Methods We extended previously published, dynamic, age-structured models of helminthiases transmission to simulate costs and disability averted with integrated MDA (of praziquantel and albendazole) for schistosomiasis and Soil-Transmitted Helminthiasis. We calibrated the model to data for prevalence and intensity of species-specific helminth infection from surveys undertaken in four communities in Cote d'Ivoire between March, 1997, and September, 2010. We simulated a 15-year treatment programme with 75% coverage in only school-aged children; school-aged children and preschool-aged children; adults; and the entire community. Treatment costs were estimated at US$0·74 for school-aged children and $1·74 for preschool-aged children and adults. The incremental cost-effectiveness ratio (ICER) was calculated in 2014 US dollars per disability-adjusted life-year (DALY) averted. Findings Expanded community-wide treatment was highly cost effective compared with treatment of only school-aged children (ICER $167 per DALY averted) and WHO guidelines (ICER $127 per DALY averted), and remained highly cost effective even if treatment costs for preschool-aged children and adults were ten times greater than those for school-aged children. Community-wide treatment remained highly cost effective even when elimination of helminth infections was not achieved. These findings were robust across the four diverse communities in Cote d'Ivoire, only one of which would have received annual MDA for both schistosomiasis and Soil-Transmitted Helminthiasis under the latest WHO guidelines. Treatment every 6 months was also highly cost effective in three out of four communities. Interpretation Integrated, community-wide MDA programmes for schistosomiasis and Soil-Transmitted Helminthiasis can be highly cost effective, even in communities with low disease burden in any helminth group. These results support an urgent need to re-evaluate current global guidelines for helminthiases control programmes to include community-wide treatment, increased treatment frequency, and consideration for lowered prevalence thresholds for integrated treatment. Funding Stanford University Medical Scholars Programme, Mount Sinai Hospital-University Health Network AMO Innovation Fund.
-
Control of Soil-Transmitted Helminthiasis in Yunnan province, People's Republic of China: experiences and lessons from a 5-year multi-intervention trial.
Acta Tropica, 2014Co-Authors: Peter Steinmann, Jürg Utzinger, Zun-wei Du, Jin-yong Jiang, Ran Chen, Fang-wei Wu, Jia-xu Chen, Hui Zhou, Xiao-nong ZhouAbstract:The current global strategy for the control of Soil-Transmitted Helminthiasis emphasises periodic administration of anthelminthic drugs to at-risk populations. However, this approach fails to address the root social and ecological causes of Soil-Transmitted Helminthiasis. For sustainable control, it has been suggested that improvements in water, sanitation and hygiene behaviour are required. We designed a 5-year multi-intervention trial in Menghai county, Yunnan province, People's Republic of China. Three different interventions were implemented, each covering a village inhabited by 200-350 people. The interventions consisted of (i) initial health education at study inception and systematic treatment of all individuals aged ≥2 years once every year with a single dose of albendazole; (ii) initial health education and bi-annual albendazole administration; and (iii) bi-annual treatment coupled with latrine construction at family level and regular health education. Interventions were rigorously implemented for 3 years, whilst the follow-up, which included annual albendazole distribution, lasted for 2 more years. Before the third round of treatment, the prevalence of Ascaris lumbricoides was reduced by only 2.8% in the annual treatment arm, whilst bi-annual deworming combined with latrine construction and health education resulted in a prevalence reduction of 53.3% (p>0.001). All three control approaches significantly reduced the prevalence of Trichuris trichiura and hookworm, with the highest reductions achieved when chemotherapy was combined with sanitation and health education. The prevalence of T. trichiura remained at 30% and above regardless of the intervention. Only bi-annual treatment combined with latrine construction and health education significantly impacted on the prevalence of Taenia spp., but none of the interventions significantly reduced the prevalence of Strongyloides stercoralis. Our findings support the notion that in high-endemicity areas, sustainable control of Soil-Transmitted helminth infections necessitates measures to reduce faecal environmental contamination to complement mass drug administration. However, elimination of Soil-Transmitted Helminthiasis will not be achieved in the short run even with a package of interventions, and probably requires improvements in living conditions, changes in hygiene behaviour and more efficacious anthelminthic drugs and treatment regimens.
-
Modelling the geographical distribution of Soil-Transmitted helminth infections in Bolivia
Parasites & Vectors, 2013Co-Authors: Frédérique Chammartin, Jürg Utzinger, Ronaldo G.c. Scholte, John B. Malone, Mara E Bavia, Prixia Nieto, Penelope VounatsouAbstract:Background: The prevalence of infection with the three common Soil-Transmitted helminths (i.e. Ascaris lumbricoides, Trichuris trichiura, and hookworm) in Bolivia is among the highest in Latin America. However, the spatial distribution and burden of Soil-Transmitted Helminthiasis are poorly documented. Methods: We analysed historical survey data using Bayesian geostatistical models to identify determinants of the distribution of Soil-Transmitted helminth infections, predict the geographical distribution of infection risk, and assess treatment needs and costs in the frame of preventive chemotherapy. Rigorous geostatistical variable selection identified the most important predictors of A. lumbricoides, T. trichiura, and hookworm transmission. Results: Results show that precipitation during the wettest quarter above 400 mm favours the distribution of A. lumbricoides. Altitude has a negative effect on T. trichiura. Hookworm is sensitive to temperature during the coldest month. We estimate that 38.0%, 19.3%, and 11.4% of the Bolivian population is infected with A. lumbricoides, T. trichiura, and hookworm, respectively. Assuming independence of the three infections, 48.4% of the population is infected with any Soil-Transmitted helminth. Empirical-based estimates, according to treatment recommendations by the World Health Organization, suggest a total of 2.9 million annualised treatments for the control of Soil-Transmitted Helminthiasis in Bolivia. Conclusions: We provide estimates of Soil-Transmitted helminth infections in Bolivia based on high-resolution spatial prediction and an innovative variable selection approach. However, the scarcity of the data suggests that a national survey is required for more accurate mapping that will govern spatial targeting of Soil-Transmitted Helminthiasis control.
