Neglected tropical diseases (NTDs) refers to a diverse group of parasitic and bacterial diseases that cause significant morbidity and mortality in more than 1 billion people worldwide. These diseases disproportionately affect poor and marginalized populations. Endemic to almost 150 countries, NTDs span the globe. However, the majority of the NTD burden is concentrated in low- and middle-income countries in Africa, Asia, and Latin America.
According to the World Health Organization (WHO), people living in rural areas as well as urban informal settlements are among the most affected given that lack of access to clean water, health services, adequate housing, and good sanitation contribute to NTDs’ prevalence and impact. Women and children are most at risk of infection and often face barriers to accessing treatment.
USAID is a major contributor in the global effort to prevent and control NTDs and focuses on five diseases: lymphatic filariasis, trachoma, onchocerciasis, schistosomiasis, and soil-transmitted helminthiasis. USAID’s NTD investments contribute to disease elimination, strengthening the scientific evidence, building laboratory and technical capacity, ensuring sustainable programs, and expanding partnerships.
This issue features upcoming NTD events, NTD resources, and recent studies and reports on specific diseases.
World Neglected Tropical Diseases Day, January 30, 2021 – World NTD Day brings together civil society advocates, community leaders, global health experts, and policymakers working across the diverse NTD landscape. January 30 is the second annual global day working to unify partners across sectors, countries, and disease communities to push for greater awareness and action on NTDs. Resources on the website include a Social Media Toolkit and Activities and Events.
Eliminating NTDs: Together Towards 2030—Formal Launch of the New Road Map for Neglected Tropical Diseases, January 28, 2021 – WHO will launch “Ending the Neglect to Attain the Sustainable Development Goals: A Road Map for Neglected Tropical Diseases 2021–2030,” a high-level strategic document and advocacy tool that aims to strengthen programmatic response to NTDs.
USAID Neglected Tropical Diseases Program – The USAID NTD Program targets five of the most common NTDs that have proven, cost-effective health interventions. The future is bright. USAID estimates 15 countries will eliminate at least one NTD as a public health problem within five years. Resources on the website include: Publications & Events, USAID Targeted Diseases, and more.
USAID's Act to End NTDs | East Program – This project supports NTD control and elimination efforts in 13 countries located throughout the globe in Southeast Asia, East Africa, and elsewhere. USAID’s Act to End NTDs | West Program – This project supports NTD control and elimination efforts in 11 West and Central African countries.
Neglected Tropical Diseases Fact Sheet. USAID, January 2021. Learn about USAID's Neglected Tropical Diseases Program. For 15 years, the Agency has supported more than 30 countries to combat five of the most common NTDs.
NTD Toolbox - This collection of tools, resources, training materials, videos, and guidance is intended for use by NTD program managers and other implementing staff.
Practical Approaches to Implementing WHO Guidance for Neglected Tropical Disease (NTD) Programs in the Context of COVID-19: Lymphatic Filariasis (LF) Surveys. USAID's Act to End NTDs | East and West programs, December 2020. This resource is intended to assist national NTD programs as they develop their own country-specific standard operating procedures, training materials, and supervision checklists.
The Process of Building the Priority of Neglected Tropical Diseases: A Global Policy Analysis. PLoS NTDs, August 2020. Findings from this study can help develop strategies to build the momentum and drive actions to implement the goals of the new road map for NTDs along the pathway to universal health coverage.
WASH and Health Working Together: A ‘How-to’ Guide for Neglected Tropical Disease Programmes. WHO, 2019. This toolkit provides step-by-step guidance to NTD program managers and partners on how to engage and work collaboratively with the water, sanitation, and hygiene (WASH) community to improve delivery of WASH services to underserved populations affected by NTDs.
Neglected Tropical Diseases Activities in Africa in the COVID-19 Era: The Need for a ‘Hybrid’ Approach in COVID-Endemic Times. Infectious Diseases of Poverty, January 2021. Failure to resume NTD activities will not only enhance the risk of NTD transmission, but will fail to leverage behavior change messaging on the importance of hand and face washing and improved sanitation—a common strategy for several NTDs that also reduces the risk of COVID-19 spread.
Nudge Strategies for Behavior-Based Prevention and Control of Neglected Tropical Diseases: A Scoping Review and Ethical Assessment. medRxiv, December 2020. Handwashing with soap accounted for almost half of the included nudge strategies; other strategies focused on defecation behaviors and water disinfection behaviors. Targeting health behaviors rather than diseases, hence implementing a horizontal, rather than a vertical approach, has increasingly become common practice.
Kenya Landscape Analysis for Neglected Tropical Diseases (NTDs), WASH and Behaviour Change. Sightsavers, August 2019. The purpose of this study is to present a broad national perspective on current WASH and behavior change programming taking place in Kenya related to NTD care and control.
Schistosomiasis Fact Sheet. WHO, March 2020. Schistosomiasis is an acute and chronic disease caused by parasitic worms. People are infected during routine agricultural, domestic, occupational, and recreational activities, which expose them to infested water.
Monitoring Schistosomiasis and Sanitation Interventions: The Potential of Environmental DNA. WIREs Water, November 2020. This article reports and critiques the methods currently used to monitor schistosomiasis in freshwater and soil environments and explores how environmental DNA could be used to better understand and monitor environmental contamination in relation to sanitation.
Contextual and Psychosocial Factors Influencing the Use of Safe Water Sources: A Case of Madeya Village, uMkhanyakude District, South Africa. International Journal of Environmental Research and Public Health, February 2020. The objective of this study is to identify critical behavior change factors that reduce risk of schistosomiasis transmission in a South African village.
Cost of Interventions to Control Schistosomiasis: A Systematic Review of the Literature. PLoS NTDs, March 2020. The authors review the literature on costs related to public health interventions against schistosomiasis to strengthen the current evidence base.
Chlorination of Schistosoma Mansoni Cercariae. PLoS NTDs, August 2020. This study has rigorously tested the effectiveness of chlorination against S. mansoni cercariae. Chlorination experiments indicate that this parasite is sensitive to chlorine and that a higher concentration of chlorine is required when water pH is high and the temperature is low.
Water, Sanitation and Behaviour Change for Schistosomiasis-Endemic Communities. SCI Foundation, July 2020. It can be assumed that a water, sanitation, and behavior change programming approach that does not respond to the specific local context is unlikely to result in uptake and use of infrastructure and in sufficient shifts in behavioral practices in endemic communities.
Human Water Contact Patterns in Active Schistosomiasis Endemic Areas. Journal of Water and Health, October 2020. Provision of adequate pipe-borne water, good sanitation, and improved knowledge of the schistosome life cycle among the community members will reduce the high rate of human water contacts.
A Systematic Review and Meta-Analysis Quantifying Schistosomiasis Infection Burden in Pre-School Aged Children (PreSAC) in Sub-Saharan Africa for the Period 2000–2020. PLoS One, December 2020. Schistosomiasis infection among preschool aged children 6 years old and below is high. This indicates the importance of including this age group in treatment programs to reduce infection prevalence and long-term morbidities.
Soil-Transmitted Helminths (STH)
The impact of Worms and Ladders, an Innovative Health Educational Board Game on Soil-Transmitted Helminthiasis Control in Abeokuta, Southwest Nigeria. PLoS NTDs, September 2020. Findings show that the worm burden dropped significantly among children who played the newly developed game, compared to other children who played another game. The knowledge, attitude, and practices of the children as regards STH also improved significantly.
Natural Wastewater Treatment Systems for Prevention and Control of Soil-Transmitted Helminths. Water Quality: Science, Assessments and Policy, May 2020. This chapter explains the role of natural wastewater treatment systems as sustainable sanitation facilities in removing STH from wastewater and therefore preventing disease transmission.
Prevalence and Intensity of Soil-Transmitted Helminth Infections of Children in Sub-Saharan Africa, 2000–18: A Geospatial Analysis. Lancet Global Health, January 2021. Estimates of soil-transmitted helminth prevalence and intensity among children in sub-Saharan Africa highlight substantial differences in the changing burden of infection between and within countries.
Prevalence, Risk Factors and Health Consequences of Soil-Transmitted Helminth Infection on the Bijagos Islands, Guinea Bissau: A Community-Wide Cross-Sectional Study. PLoS NTDs, December 2020. This study uncovered an ongoing reservoir of STH infection despite high coverage with mass drug administration, high rates of morbidity alongside the STH infection, and a clear association between STH infection and inadequate sanitation.
Hand Hygiene Intervention to Optimize Helminth Infection Control: Design and Baseline Results of Mikono Safi–An Ongoing School-Based Cluster-Randomised Controlled Trial in NW Tanzania. PLoS One, December 2020. The study is being conducted in the context of regular school-based annual deworming campaigns and aims to determine the effectiveness of an innovative combination intervention of promoting handwashing with water and soap at key times and reducing STH prevalence.
Prevalence of Soil-Transmitted Helminthes and Its Association with Water, Sanitation, Hygiene among Schoolchildren and Barriers for Schools Level Prevention in Technology Villages of Hawassa University: Mixed Design. PLoS One, September 2020. Positive associations were identified between STH infection and large family size, inadequate knowledge about STHs, owning toilets that were not easy to clean, the absence of separate toilets for males and females, a toilet distance greater than 100 meters from the classroom, and not washing hands before a meal.
Household Finished Flooring and Soil-Transmitted Helminth and Giardia Infections among Children in Rural Bangladesh and Kenya: A Prospective Cohort Study. MedRxiv, June 2020. In low-resource settings, living in households with finished floors over a two-year period was associated with lower prevalence of Giardia and certain STH in children.
Trachoma Fact Sheet. WHO, August 2020. Trachoma is a disease of the eye that is a public health concern in 44 countries and is responsible for the blindness or visual impairment of about 1.9 million people.
Viability PCR Shows that Non-Ocular Surfaces Could Contribute to Transmission of Chlamydia Trachomatis Infection in Trachoma. PLoS NTDs, July 2020. Plastic, cotton cloth, and skin may contribute to transmission of the Chlamydia trachomatis strains that cause trachoma, by acting as sites where reservoirs of bacteria are deposited and later collected and transferred mechanically into previously uninfected eyes.
How Should We Measure Face Washing in Trachoma Elimination Programmes? BugBitten, December 2020. The results presented highlight the need for further research into a reliable marker for face washing to guide trachoma and WASH campaigns.
Seroprevalence of Antibodies Against Chlamydia Trachomatis and Enteropathogens and Distance to the Nearest Water Source among Young Children in the Amhara Region of Ethiopia. PLoS NTDs, September 2020. Integrated sero-surveillance is a promising avenue to explore the complexities of multi-pathogen exposure as well as to investigate associations between WASH–related exposures and disease transmission.
Facial Cleanliness Indicators by Time of Day: Results of a Cross-Sectional Trachoma Prevalence Survey in Senegal. Parasites and Vectors, November 2020. A reliable, standardized, practical measure of face washing is needed, which reflects hygiene behavior rather than environmental or cultural factors.
A Guide for Developing an Integrated, Evidence and Theory Based Water, Sanitation and Hygiene (WASH) and Trachoma F and E Programme. SNV, January 2020. This WASH and Trachoma facial cleanliness and environmental improvement programming strategy is grounded in the results of a cross-sectional study of environmental health conditions, and the hygiene and sanitation related practices, perceptions, and knowledge of community members.
Detecting Extra-Ocular Chlamydia Trachomatis in a Trachoma-Endemic Community in Ethiopia: Identifying Potential Routes of Transmission. PLoS NTDs, March 2020. Findings suggest several plausible ocular Chlamydia trachomatis transmission routes between people, within and between households, which would need to be simultaneously addressed within communities to suppress transmission.
Milestones in the Fight to Eliminate Trachoma. Ophthalmic and Physiological Optics, February 2020. Eight milestones are presented. Among these are discovery of the causative agent; development of a clinical grading scheme; use of the SAFE strategy (surgery, antibiotics, facial cleanliness, and environmental improvement); and the Global Trachoma Mapping Project.
Terminating Trachoma: How Myanmar Eliminated Blinding Trachoma. WHO, September 2020. Surveys conducted to map trachoma as a public health problem have specifically taken into consideration the proportion of households with latrine facilities and accessible supply of water to maintain hygiene.
Poor WASH (Water, Sanitation, and Hygiene) Conditions Are Associated with Leprosy in North Gondar, Ethiopia. International Journal of Environmental Research and Public Health, August 2020. Results suggest that leprosy transmission may be related to WASH adequacy and access as well as to schistosomiasis co-infection.
The Impact of Illegal Waste Sites on the Transmission of Zoonotic Cutaneous Leishmaniasis in Central Tunisia. International Journal of Environmental Research and Public Health, December 2020. Illegal waste disposal represents a risk health factor for vector-borne diseases by providing shelter for rodents and their ectoparasites.
COVID-19 and Neglected Tropical Diseases in Africa: Impacts, Interactions, Consequences. International Health, July 2020. In this editorial, the authors discuss the potential impact of COVID-19 on NTD programs as health services seek to function in the newly changed COVID-19 environment.
Dengue and Severe Dengue Fact Sheet. WHO, June 2020. Dengue prevention and control depend on effective vector control measures. Sustained community involvement can improve vector control efforts substantially.