Accelerating Progress Towards the 2030 Neglected Tropical Diseases Targets: How Can Quantitative Modeling Support Programmatic Decisions?

Over the past decade, considerable progress has been made in the control, elimination, and eradication of neglected tropical diseases (NTDs). Despite these advances, most NTD programs have recently experienced important setbacks; for example, NTD interventions were some of the most frequently and severely impacted by service disruptions due to the coronavirus disease 2019 (COVID-19) pandemic. Mathematical modeling can help inform selection of interventions to meet the targets set out in the NTD road map 2021-2030, and such studies should prioritize questions that are relevant for decision-makers, especially those designing, implementing, and evaluating national and subnational programs. In September 2022, the World Health Organization hosted a stakeholder meeting to identify such priority modeling questions across a range of NTDs and to consider how modeling could inform local decision making. Here, we summarize the outputs of the meeting, highlight common themes in the questions being asked, and discuss how quantitative modeling can support programmatic decisions that may accelerate progress towards the 2030 targets.

Validating a questionnaire to identify women in the first trimester of pregnancy during preventive chemotherapy interventions against soil-transmitted helminths in northwestern Tanzania.

Objectives: To evaluate the performance of a questionnaire in assessing the pregnancy status of women of reproductive age during preventive chemotherapy interventions. Methods: A questionnaire (20 questions) was administered to 1217 women of reproductive age (≥18 years) from Ilemela and Buchosa districts, northwestern Tanzania. A single urine sample was collected from each of them and tested using a rapid pregnancy test for presence of pregnant. Results: Overall, 10.8% (132/1217) of the women reported to be pregnant at the specific question in the questionnaire. The rapid pregnancy test identified 15.1% (184/1217) of the women to be pregnant. In total, 86.4% (114/132) of the women who reported to be pregnant during the interview were confirmed to be pregnant using the rapid pregnant test. The question on pregnancy demonstrated an overall sensitivity of 62% and specificity of 98.3%. Conclusions: The questionnaire performance was not completely satisfactory; however, it managed to identify pregnant women in the first trimester. The question on the last date of the start of the menstrual period yield the highest sensitivity and appeared to be the key one used in combination with other questions. Further validation of these results in other countries with different cultures are recommended to fully evaluate the performance of this method.

Progress towards the implementation of control programmes for strongyloidiasis in endemic areas: estimation of number of adults in need of ivermectin for strongyloidiasis.

The World Health Organization has started a process to issue guidelines for the control of strongyloidiasis. The guidelines might recommend to implement preventive chemotherapy (PC) at community level (i.e. to all individuals above 5 years of age), over a defined prevalence threshold. We previously estimated the number of school-age children (SAC) who would need PC. Here we estimate the number of people above 15 years of age who might be included in PC for strongyloidiasis. Based on previous Strongyloides prevalence estimates and on countries' age distribution, we retrieved the number of adults in need of PC. We then subtracted the number of people already involved in ivermectin mass distribution for the elimination of onchocerciasis and lymphatic filariasis and people living in countries where Loa loa is endemic. The number of adults to be involved in PC was estimated at 905.4 (95% confidence interval (CI): 520.6-1177.2), 660.2 (95% CI: 512.7-1214.9), and 512.1 (95% CI: 276-719.4) million people, when the strongyloidiasis prevalence threshold for implementing PC was set to 10%, 15% and 20%, respectively. Estimates at country level are also provided.These estimates might help endemic countries wishing to implement PC for strongyloidiasis to allocate resources to include adults in addition to SAC in control programmes. This article is part of the Theo Murphy meeting issue 'Strongyloides: omics to worm-free populations'.

Optimal control analysis of a transmission interruption model for the soil-transmitted helminth infections in Kenya.

Kenya is among the countries endemic for soil-transmitted helminthiasis (STH) with over 66 subcounties and over 6 million individuals being at-risk of infection. Currently, the country is implementing mass drug administration (MDA) to all the at-risk groups as the mainstay control strategy. This study aimed to develop and analyze an optimal control (OC) model, from a transmission interruption model, to obtain an optimal control strategy from a mix of three strategies evaluated. The study used the Pontryagin's maximum principle to solve, numerically, the OC model. The analysis results clearly demonstrated that water and sanitation when implemented together with the MDA programme offer the best chances of eliminating these tenacious and damaging parasites. Thus, we advocate for optimal implementation of the combined mix of the two interventions in order to achieve STH elimination in Kenya, and globally, in a short implementation period of less than eight years.

Model-based geostatistical design and analysis of prevalence for soil-transmitted helminths in Kenya: Results from ten-years of the Kenya national school-based deworming programme.

Background: Kenya is endemic for soil-transmitted helminths (STH) with over 6 million children in 27 counties currently at-risk. A national school-based deworming programme (NSBDP) was launched in 2012 with a goal to eliminate parasitic worms as a public health problem. This study used model-based geostatistical (MBG) approach to design and analyse the impact of the NSBDP and inform treatment strategy changes. Methods: A cross-sectional study was used to survey 200 schools across 27 counties in Kenya. The study design, school selection and analysis followed the MBG approach which incorporated historical data on treatment, morbidity and environmental covariates to efficiently predict the helminths prevalence in Kenya. Results: Overall, the NSBDP geographic area prevalence for any STH was estimated to sit between 2 % and <10 % with a high predictive probability of >0.999. Species-specific thresholds were between 2 % and <10 % for Ascaris lumbricoides, 0 % to <2 % for hookworm, and 0 % to <2 % for Trichuris trichiura, all with high predictive probability of >0.999. Conclusions: Based on the World Health Organization guidelines, STH treatment requirements can now be confidently refined. Ten counties may consider suspending treatment and implement appropriate surveillance system, while another 10 will require treatment once every two years, and the remaining seven will require treatment once every year.

Schistosomiasis elimination in Madagascar: challenges and opportunities for implementing the new WHO guidelines.

Madagascar is one of the countries with the highest burden of schistosomiasis worldwide. The release from the WHO of the new 2021-2030 neglected tropical disease (NTD) roadmap alongside with the schistosomiasis guidelines sets the ambitious goal of eliminating schistosomiasis as a public health problem worldwide. In Madagascar, implementation barriers exist. This paper has the objective of identifying strengths, weaknesses, opportunities and threats in order to build on their basis practices and policies that can help the country to align with the international global health agenda and reach the ambitious goal set by the WHO.

A general framework to support cost-efficient fecal egg count methods and study design choices for large-scale STH deworming programs-monitoring of therapeutic drug efficacy as a case study.

BACKGROUND: Soil-transmitted helminth (STH) control programs currently lack evidence-based recommendations for cost-efficient survey designs for monitoring and evaluation. Here, we present a framework to provide evidence-based recommendations, using a case study of therapeutic drug efficacy monitoring based on the examination of helminth eggs in stool. METHODS: We performed an in-depth analysis of the operational costs to process one stool sample for three diagnostic methods (Kato-Katz, Mini-FLOTAC and FECPAKG2). Next, we performed simulations to determine the probability of detecting a truly reduced therapeutic efficacy for different scenarios of STH species (Ascaris lumbricoides, Trichuris trichiura and hookworms), pre-treatment infection levels, survey design (screen and select (SS); screen, select and retest (SSR) and no selection (NS)) and number of subjects enrolled (100-5,000). Finally, we integrated the outcome of the cost assessment into the simulation study to estimate the total survey costs and determined the most cost-efficient survey design. PRINCIPAL FINDINGS: Kato-Katz allowed for both the highest sample throughput and the lowest cost per test, while FECPAKG2 required both the most laboratory time and was the most expensive. Counting of eggs accounted for 23% (FECPAKG2) or ≥80% (Kato-Katz and Mini-FLOTAC) of the total time-to-result. NS survey designs in combination with Kato-Katz were the most cost-efficient to assess therapeutic drug efficacy in all scenarios of STH species and endemicity. CONCLUSIONS/SIGNIFICANCE: We confirm that Kato-Katz is the fecal egg counting method of choice for monitoring therapeutic drug efficacy, but that the survey design currently recommended by WHO (SS) should be updated. Our generic framework, which captures laboratory time and material costs, can be used to further support cost-efficient choices for other important surveys informing STH control programs. In addition, it can be used to explore the value of alternative diagnostic techniques, like automated egg counting, which may further reduce operational costs. TRIAL REGISTRATION: ClinicalTrials.gov NCT03465488.

Comprehensive framework for integrated action on the prevention, diagnosis, and management of anemia: An introduction.

The World Health Organization (WHO) announced in 2021 a commitment to develop a comprehensive framework for integrated action on the prevention, diagnosis, and management of anemia and to establish an Anaemia Action Alliance to support the implementation of the framework. WHO commissioned four background papers to provide reflections about the most pressing issues to be addressed for accelerating reductions in the prevalence of anemia. Here, we provide a complete vision of the framework.

Eliminating morbidity caused by neglected tropical diseases by 2030.

The objective of this manuscript is to provide selective examples of the work of the Pan American Health Organization/World Health Organization (PAHO/WHO) Collaborating Centre for Research and Training in Parasite Epidemiology and Control which contribute to the WHO goal of eliminating neglected tropical diseases by 2030. This PAHO/WHO CC specifically aligns its activities with the Sustainable Development Goals and with the goals outlined in the WHO Road Map for Neglected Tropical Diseases 2021-2030. Its role is to contribute to advancing global action on NTDs, primarily through policy development and knowledge translation. Three important projects have recently been completed: 1. Finalizing the Monitoring and Evaluation Framework for the NTD Road Map (published May 2021; this PAHO/WHO CC was a member of the working group); 2. Developing new guidelines for the preventive chemotherapy of Taenia solium taeniasis (published September 2021; this PAHO/WHO CC was co-Chair; and 3. Formulating a policy brief on deworming for adolescent girls and women of reproductive age (published January 2022; this PAHO/WHO CC is co-lead). These projects are the result of the integration of expertise and experience from multiple partners, including from PAHO and WHO (where both organizations provided key leadership), this PAHO/WHO CC, government ministries, civil society organizations and universities, among others. In conclusion, this PAHO/WHO CC contributes timely guidance to country-led evidence-informed public health policy, to cost-effective program implementation and to the identification of priority research topics - all focused, ultimately, on eliminating NTD-attributable morbidity by 2030.

El objetivo de este artículo es proporcionar ejemplos seleccionados de la labor del centro colaborador de investigación y capacitación en epidemiología y control de parásitos de la Organización Panamericana de la Salud/Organización Mundial de la Salud (OPS/OMS), que contribuye al objetivo de la OMS de eliminar las enfermedades tropicales desatendidas para el 2030. Este centro colaborador de la OPS/OMS alinea sus actividades específicamente con los Objetivos de Desarrollo Sostenible y con los objetivos descritos en la Hoja de ruta sobre enfermedades tropicales desatendidas 2021-2030 de la OMS. Su función es contribuir al avance de las medidas mundiales sobre las enfermedades tropicales desatendidas, principalmente mediante la elaboración de políticas y la traducción de conocimiento. Recientemente se han completado tres proyectos importantes: 1) finalización del marco de seguimiento y evaluación de la Hoja de ruta sobre enfermedades tropicales desatendidas (publicado en mayo del 2021; este centro colaborador de la OPS/OMS formó parte del grupo de trabajo); 2) elaboración de nuevas directrices para la quimioterapia preventiva de la teniasis por Taenia solium (publicado en septiembre del 2021; este centro colaborador fue copresidente); y 3) formulación de un informe de políticas sobre la desparasitación de las adolescentes y las mujeres en edad reproductiva (publicado en enero del 2022; este centro colaborador fue coautor). Estos proyectos son el resultado de la integración del conocimiento y la experiencia de múltiples asociados, como la OPS y la OMS (ambas organizaciones ofrecieron un liderazgo clave), este centro colaborador de la OPS/OMS, así como varios ministerios gubernamentales, organizaciones de la sociedad civil y universidades, entre otros. En conclusión, este centro colaborador de la OPS/OMS ofrece orientaciones oportunas para las políticas de salud pública basadas en la evidencia lideradas por los países, la ejecución de programas costo-efectivos y la determinación de los temas de investigación prioritarios, todo ello destinado, en última instancia, a eliminar la morbilidad atribuible a las enfermedades tropicales desatendidas para el 2030.

O objetivo deste manuscrito é fornecer exemplos seletivos do trabalho do Centro Colaborador de Pesquisa e Treinamento em Epidemiologia e Controle de Parasitos da Organização Pan-Americana da Saúde/Organização Mundial da Saúde (OPAS/OMS) que contribuem para a meta da OMS de eliminar até 2030 as doenças tropicais negligenciadas. Este CC da OPAS/OMS alinha especificamente suas atividades com os Objetivos de Desenvolvimento Sustentável e com as metas delineadas no Roteiro da OMS para Doenças Tropicais Negligenciadas 2021-2030. Seu papel é contribuir para o avanço da ação global contra doenças tropicais negligenciadas, principalmente por meio do desenvolvimento de políticas e da tradução de conhecimentos. Três importantes projetos foram concluídos recentemente: 1. Finalização da Estrutura de Monitoramento e Avaliação do Roteiro para as DTN (publicada em maio de 2021 ­ este CC da OPAS/OMS foi membro do grupo de trabalho); 2. Desenvolvimento de novas diretrizes para a quimioprofilaxia da teníase por Taenia solium (publicado em setembro de 2021 ­ este CC da OPAS/OMS foi copresidente); e 3. Formulação de orientação para políticas de desparasitação para adolescentes e mulheres em idade reprodutiva (publicado em janeiro de 2022 ­ este CC da OPAS/OMS foi cogestor). Esses projetos são o resultado da integração de conhecimentos e experiência de múltiplos parceiros, incluindo a OPAS e a OMS (onde ambas as organizações forneceram liderança essencial), este CC da OPAS/OMS, ministérios governamentais, organizações da sociedade civil e universidades, entre outros. Em suma, este CC da OPAS/OMS contribui com orientações oportunas para uma política de saúde pública liderada pelos países e informada com base em evidências, para a implementação de programas com boa relação custo-benefício e para a identificação de tópicos prioritários de pesquisa ­ todos focados, em última análise, na eliminação da morbidade atribuível às DTN até 2030.

Eliminating morbidity caused by neglected tropical diseases by 2030

[ABSTRACT]. The objective of this manuscript is to provide selective examples of the work of the Pan American Health Orga- nization/World Health Organization (PAHO/WHO) Collaborating Centre for Research and Training in Parasite Epidemiology and Control which contribute to the WHO goal of eliminating neglected tropical diseases by 2030. This PAHO/WHO CC specifically aligns its activities with the Sustainable Development Goals and with the goals outlined in the WHO Road Map for Neglected Tropical Diseases 2021-2030. Its role is to contribute to advancing global action on NTDs, primarily through policy development and knowledge translation. Three important projects have recently been completed: 1. Finalizing the Monitoring and Evaluation Framework for the NTD Road Map (published May 2021; this PAHO/WHO CC was a member of the working group); 2. Devel- oping new guidelines for the preventive chemotherapy of Taenia solium taeniasis (published September 2021; this PAHO/WHO CC was co-Chair; and 3. Formulating a policy brief on deworming for adolescent girls and women of reproductive age (published January 2022; this PAHO/WHO CC is co-lead). These projects are the result of the integration of expertise and experience from multiple partners, including from PAHO and WHO (where both organizations provided key leadership), this PAHO/WHO CC, government ministries, civil society organizations and universities, among others. In conclusion, this PAHO/WHO CC contributes timely guidance to country-led evidence-informed public health policy, to cost-effective program implementation and to the identification of priority research topics – all focused, ultimately, on eliminating NTD-attributable morbidity by 2030.

[RESUMEN]. El objetivo de este artículo es proporcionar ejemplos seleccionados de la labor del centro colaborador de investigación y capacitación en epidemiología y control de parásitos de la Organización Panamericana de la Salud/Organización Mundial de la Salud (OPS/OMS), que contribuye al objetivo de la OMS de eliminar las enfermedades tropicales desatendidas para el 2030. Este centro colaborador de la OPS/OMS alinea sus actividades específicamente con los Objetivos de Desarrollo Sostenible y con los objetivos descritos en la Hoja de ruta sobre enfermedades tropicales desatendidas 2021-2030 de la OMS. Su función es contribuir al avance de las medidas mundiales sobre las enfermedades tropicales desatendidas, principalmente mediante la elaboración de políticas y la traducción de conocimiento. Recientemente se han completado tres proyectos importantes: 1) finalización del marco de seguimiento y evaluación de la Hoja de ruta sobre enfermedades tropicales desatendidas (publicado en mayo del 2021; este centro colaborador de la OPS/OMS formó parte del grupo de trabajo); 2) elaboración de nuevas directrices para la quimioterapia preventiva de la teniasis por Taenia solium (publicado en septiembre del 2021; este centro colaborador fue copresidente); y 3) formulación de un informe de políticas sobre la desparasitación de las adolescentes y las mujeres en edad reproductiva (publicado en enero del 2022; este centro colaborador fue coautor). Estos proyectos son el resultado de la integración del conocimiento y la experiencia de múltiples asociados, como la OPS y la OMS (ambas organi- zaciones ofrecieron un liderazgo clave), este centro colaborador de la OPS/OMS, así como varios ministerios gubernamentales, organizaciones de la sociedad civil y universidades, entre otros. En conclusión, este centro colaborador de la OPS/OMS ofrece orientaciones oportunas para las políticas de salud pública basadas en la evidencia lideradas por los países, la ejecución de programas costo-efectivos y la determinación de los temas de investigación prioritarios, todo ello destinado, en última instancia, a eliminar la morbilidad atribuible a las enfermedades tropicales desatendidas para el 2030.

[RESUMO]. O objetivo deste manuscrito é fornecer exemplos seletivos do trabalho do Centro Colaborador de Pesquisa e Treinamento em Epidemiologia e Controle de Parasitos da Organização Pan-Americana da Saúde/Organi- zação Mundial da Saúde (OPAS/OMS) que contribuem para a meta da OMS de eliminar até 2030 as doenças tropicais negligenciadas. Este CC da OPAS/OMS alinha especificamente suas atividades com os Objetivos de Desenvolvimento Sustentável e com as metas delineadas no Roteiro da OMS para Doenças Tropicais Negligenciadas 2021-2030. Seu papel é contribuir para o avanço da ação global contra doenças tropicais negligenciadas, principalmente por meio do desenvolvimento de políticas e da tradução de conhecimentos. Três importantes projetos foram concluídos recentemente: 1. Finalização da Estrutura de Monitoramento e Avaliação do Roteiro para as DTN (publicada em maio de 2021 – este CC da OPAS/OMS foi membro do grupo de trabalho); 2. Desenvolvimento de novas diretrizes para a quimioprofilaxia da teníase por Taenia solium (publicado em setembro de 2021 – este CC da OPAS/OMS foi copresidente); e 3. Formulação de orientação para políticas de desparasitação para adolescentes e mulheres em idade reprodutiva (publicado em janeiro de 2022 – este CC da OPAS/OMS foi cogestor). Esses projetos são o resultado da integração de conhecimen- tos e experiência de múltiplos parceiros, incluindo a OPAS e a OMS (onde ambas as organizações forneceram liderança essencial), este CC da OPAS/OMS, ministérios governamentais, organizações da sociedade civil e universidades, entre outros. Em suma, este CC da OPAS/OMS contribui com orientações oportunas para uma política de saúde pública liderada pelos países e informada com base em evidências, para a implementação de programas com boa relação custo-benefício e para a identificação de tópicos prioritários de pesquisa – todos focados, em última análise, na eliminação da morbidade atribuível às DTN até 2030.

Use of a "tablet pole" for the administration of ivermectin for strongyloidiasis in a field study in Ecuador.

BACKGROUND: Establishment of efficient control programs for strongyloidiasis, the infection by Strongyloides stercoralis, is among the World Health Organization (WHO) targets for 2030. Ivermectin is a drug of choice for strongyloidiasis, but its weight-based administration can be unfeasible in remote areas. We evaluated a WHO tablet pole for administration of ivermectin in school-age children living in remote villages in Ecuador. METHODS: Children were enrolled in 16 villages in Esmeraldas Province of Ecuador, between July 2021 and June 2022. The pole identified four height intervals corresponding to ivermectin doses going from one to four tablets. For each child, we calculated the dose (µg/kg) administered with both weight-based and pole-based administration. Results were classified as follows: optimal dose, acceptable, overdose, underdose. Agreement between the two methods for estimating the number of tablets was assessed with Cohen's kappa coefficient. Estimations were reported with 95% confidence intervals (CIs). RESULTS: Total of 778 children (47.3% female) were enrolled, with median age of 9.59 years (interquartile range: 7.42‒11.22). Optimal dose was achieved for a higher proportion of children when assessed with weight (37.9%) than with pole (25.7%). Underdose and overdose were more frequent with the pole (8.3% and 19.2% children, respectively) than with the weight-based (3.7% and 6.0%, respectively) administration. Agreement between weight-based and pole-based administration was moderate: 0.56 (95% CI 0.51, 0.61). The two methods indicated the same number of tablets in 71.6% (95% CI 0.684, 0.748) cases. CONCLUSIONS: In our setting, the tablet pole could be a valid alternative. The tool needs further evaluation in different populations.

Adjustments in case of overweight and obesity to the WHO tablet pole for praziquantel administration.

The WHO tablet pole was developed in 2001 to facilitate the distribution of praziquantel in large-scale treatment campaigns for the control of schistosomiasis. Although a number of field studies have confirmed the accuracy of the tool in normal individuals, some studies have demonstrated that overweight and obese individuals are underdosed. This article proposes an adjustment in the number of praziquantel tablets for treatment of individuals who are overweight or obese according to their body mass index. We demonstrate that by adding an extra tablet of praziquantel to that indicated by the WHO tablet pole, the tool provides the appropriate number of tablets for treatment of overweight and obese individuals. We also propose a pictogram be included in the instructions for use of the WHO tablet pole.

Eliminating morbidity caused by neglected tropical diseases by 2030 / Eliminar la morbilidad causada por las enfermedades tropicales desatendidas para el 2030 / Eliminação até 2030 da morbidade causada pelas doenças tropicais negligenciadas

ABSTRACT The objective of this manuscript is to provide selective examples of the work of the Pan American Health Organization/World Health Organization (PAHO/WHO) Collaborating Centre for Research and Training in Parasite Epidemiology and Control which contribute to the WHO goal of eliminating neglected tropical diseases by 2030. This PAHO/WHO CC specifically aligns its activities with the Sustainable Development Goals and with the goals outlined in the WHO Road Map for Neglected Tropical Diseases 2021-2030. Its role is to contribute to advancing global action on NTDs, primarily through policy development and knowledge translation. Three important projects have recently been completed: 1. Finalizing the Monitoring and Evaluation Framework for the NTD Road Map (published May 2021; this PAHO/WHO CC was a member of the working group); 2. Developing new guidelines for the preventive chemotherapy of Taenia solium taeniasis (published September 2021; this PAHO/WHO CC was co-Chair; and 3. Formulating a policy brief on deworming for adolescent girls and women of reproductive age (published January 2022; this PAHO/WHO CC is co-lead). These projects are the result of the integration of expertise and experience from multiple partners, including from PAHO and WHO (where both organizations provided key leadership), this PAHO/WHO CC, government ministries, civil society organizations and universities, among others. In conclusion, this PAHO/WHO CC contributes timely guidance to country-led evidence-informed public health policy, to cost-effective program implementation and to the identification of priority research topics - all focused, ultimately, on eliminating NTD-attributable morbidity by 2030.

RESUMEN El objetivo de este artículo es proporcionar ejemplos seleccionados de la labor del centro colaborador de investigación y capacitación en epidemiología y control de parásitos de la Organización Panamericana de la Salud/Organización Mundial de la Salud (OPS/OMS), que contribuye al objetivo de la OMS de eliminar las enfermedades tropicales desatendidas para el 2030. Este centro colaborador de la OPS/OMS alinea sus actividades específicamente con los Objetivos de Desarrollo Sostenible y con los objetivos descritos en la Hoja de ruta sobre enfermedades tropicales desatendidas 2021-2030 de la OMS. Su función es contribuir al avance de las medidas mundiales sobre las enfermedades tropicales desatendidas, principalmente mediante la elaboración de políticas y la traducción de conocimiento. Recientemente se han completado tres proyectos importantes: 1) finalización del marco de seguimiento y evaluación de la Hoja de ruta sobre enfermedades tropicales desatendidas (publicado en mayo del 2021; este centro colaborador de la OPS/OMS formó parte del grupo de trabajo); 2) elaboración de nuevas directrices para la quimioterapia preventiva de la teniasis por Taenia solium (publicado en septiembre del 2021; este centro colaborador fue copresidente); y 3) formulación de un informe de políticas sobre la desparasitación de las adolescentes y las mujeres en edad reproductiva (publicado en enero del 2022; este centro colaborador fue coautor). Estos proyectos son el resultado de la integración del conocimiento y la experiencia de múltiples asociados, como la OPS y la OMS (ambas organizaciones ofrecieron un liderazgo clave), este centro colaborador de la OPS/OMS, así como varios ministerios gubernamentales, organizaciones de la sociedad civil y universidades, entre otros. En conclusión, este centro colaborador de la OPS/OMS ofrece orientaciones oportunas para las políticas de salud pública basadas en la evidencia lideradas por los países, la ejecución de programas costo-efectivos y la determinación de los temas de investigación prioritarios, todo ello destinado, en última instancia, a eliminar la morbilidad atribuible a las enfermedades tropicales desatendidas para el 2030.

RESUMO O objetivo deste manuscrito é fornecer exemplos seletivos do trabalho do Centro Colaborador de Pesquisa e Treinamento em Epidemiologia e Controle de Parasitos da Organização Pan-Americana da Saúde/Organização Mundial da Saúde (OPAS/OMS) que contribuem para a meta da OMS de eliminar até 2030 as doenças tropicais negligenciadas. Este CC da OPAS/OMS alinha especificamente suas atividades com os Objetivos de Desenvolvimento Sustentável e com as metas delineadas no Roteiro da OMS para Doenças Tropicais Negligenciadas 2021-2030. Seu papel é contribuir para o avanço da ação global contra doenças tropicais negligenciadas, principalmente por meio do desenvolvimento de políticas e da tradução de conhecimentos. Três importantes projetos foram concluídos recentemente: 1. Finalização da Estrutura de Monitoramento e Avaliação do Roteiro para as DTN (publicada em maio de 2021 - este CC da OPAS/OMS foi membro do grupo de trabalho); 2. Desenvolvimento de novas diretrizes para a quimioprofilaxia da teníase por Taenia solium (publicado em setembro de 2021 - este CC da OPAS/OMS foi copresidente); e 3. Formulação de orientação para políticas de desparasitação para adolescentes e mulheres em idade reprodutiva (publicado em janeiro de 2022 - este CC da OPAS/OMS foi cogestor). Esses projetos são o resultado da integração de conhecimentos e experiência de múltiplos parceiros, incluindo a OPAS e a OMS (onde ambas as organizações forneceram liderança essencial), este CC da OPAS/OMS, ministérios governamentais, organizações da sociedade civil e universidades, entre outros. Em suma, este CC da OPAS/OMS contribui com orientações oportunas para uma política de saúde pública liderada pelos países e informada com base em evidências, para a implementação de programas com boa relação custo-benefício e para a identificação de tópicos prioritários de pesquisa - todos focados, em última análise, na eliminação da morbidade atribuível às DTN até 2030.

Reduction in DALYs lost due to soil-transmitted helminthiases and schistosomiasis from 2000 to 2019 is parallel to the increase in coverage of the global control programmes.

Preventive chemotherapy interventions for the control of soil-transmitted helminthiases (STH) and schistosomiasis scaled up from a global coverage level of around 5% in the year 2000 to a coverage that surpassed 60% in the year 2019. The present paper analyses the concomitant reduction in the number of disability-adjusted life years (DALYs) lost due to STH and schistosomiasis during the same period, from 6.3 to 3.5 million DALYs. The cumulative gain during the 19-year period was estimated at over 26 million DALYs. Given the low cost of the intervention, our study suggests that deworming for STH and schistosomiasis is one of the most cost-effective public health interventions.

Impact of preventive chemotherapy on transmission of soil-transmitted helminth infections in Pemba Island, United Republic of Tanzania, 1994-2021.

Soil-transmitted helminth (STH) infections cause significant morbidity in children and women of reproductive age. The World Health Organization (WHO) recommends preventive chemotherapy (PC) of at-risk populations with anthelminthics to control these infections. Historically, STH are very intensively transmitted in Pemba Island (Zanzibar). A survey conducted in 1994 in 12 schools estimated a STH prevalence near to 100%. This extremely high prevalence induced the introduction of PC in the island; initially, however, PC was not regularly administered because of difficulties linked to drug procurement. A second STH survey, conducted in 2011, in 24 schools estimated a prevalence of STH of 89%; after this survey, PC was regularly administered until 2018. We conducted a survey in 2021 using the same method as that used in 2011. The prevalence of STH was evaluated at 80% (95% CI 78.1-81.5) and most of the STH cases were due to Trichuris trichiura. More than 32% (95% CI 30.3-34.0) of the children investigated had infections of moderate or heavy intensity. PC has been conducted for over 25 years in Pemba Island. However, despite its beneficial impact, both the prevalence and the intensity of STH infections remain high, and the intervention has been insufficient in controlling STH morbidity. This is probably due to a combination of irregular PC, climatic conditions favourable to STH transmission, the low sensitivity of T. trichiura to benzimidazoles, high population density and poor sanitation. Improvement of sanitation coverage remains a key measure to permanently reduce the prevalence and intensity of STH. Possible changes to the present PC approaches to better control STH in Pemba would be (i) to assure high coverage in all schools, (ii) to use mebendazole instead of albendazole given its better activity on T. trichiura and (iii) to use a combination of ivermectin and mebendazole to further increase anthelminthic efficacy on T. trichiura.

Development of a public geographical information system-based website to follow the impact of control activities of soil-transmitted helminths in endemic countries.

Soil-transmitted helminth (STH) infections are among the most common neglected tropical diseases worldwide causing high morbidity and mortality rates in endemic areas. Preventive chemotherapy (PC) programmes and health education are recommended by the World Health Organization (WHO) to reduce the impact of STH in endemic countries. Following our role as WHO collaborating centre (WHO CC ITA-116), we have developed a WebGIS and a dataset to support PC programmes to monitor the impact of STH control. This vHealth presentation shows the potentiality of these tools in improving communication among WHO's regional and country offices, Ministries of Health, pharmaceutical industries and other partners.