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About NTDs

Neglected tropical diseases (NTDs) represent a group of diverse diseases that cause significant morbidity and mortality worldwide but have until recently received limited attention from the affluent regions of the world. More than 1 billion people – one-sixth of the world’s population – suffer from one or more NTDs. These diseases affect the world’s most vulnerable populations, almost exclusively poor and powerless people living in rural areas and urban slums of low-income countries. Their impact on individuals and communities is devastating. Many of them cause severe disfigurement and disabilities, including blindness.

NTDs coexist with poverty because they thrive where access to clean water and sanitation is limited, and people live without protection from disease vectors. The NTDs also are recognized as a contributor to poverty since they can impair intellectual development in children, reduce school enrollment and hinder economic productivity by limiting the ability of infected individuals to work.

Fortunately, seven of the most prevalent NTDs can be targeted using a similar public health strategy developed by the World Health Organization (WHO) known as preventive chemotherapy. This strategy involves large-scale distribution of high quality, safety-tested NTD medicines. The delivery platform for these medicines is known as mass drug administration or MDA. Due to the strong safety profile of these medicines, WHO endorses their delivery by trained, non-medical personnel, such as community volunteers and teachers. Most of the drugs needed are donated by pharmaceutical companies (Source:

Working towards NTD control and elimination by 2020

National NTD programs aim to map 100% of districts suspected to be endemic for the targeted PC NTDs, and start MDA in 100% of the districts confirmed to be endemic and meeting specific thresholds where treatment is required -- this is typically considered the “scale-up” phase of NTD program implementation. After successive years of MDA activities and implementation of complementary interventions, programs carry out impact assessments to determine whether interventions can be discontinued—the aim of this “scale-down” phase is to stop MDA in 100% of endemic districts, move into a surveillance phase and eventually validate disease elimination.

Figure 1 illustrates progress toward NTD control or elimination for each of the ENVISION-supported countries (as of September 2015). The proportion of districts at each stage of the continuum for all diseases combined at the time of this report is presented. Baseline mapping is complete for all NTDs in the majority of ENVISION countries, with some gaps remaining for multiple diseases in DRC and Ethiopia, and one disease in Indonesia, Mali, and Senegal. It is anticipated that by September 2015, all countries will have mapped all diseases, except for situations beyond the project’s control (e.g., security in DRC, Ethiopia, and Nigeria; and Ebola in Guinea).

ENVISION’s efforts are now focused on supporting countries to scale up to 100% geographic coverage of at-risk populations with MDA, with a focus on elimination of LF, trachoma, and OV where feasible. As of April 2015, the project has reached the national geographic scale for all diseases in Haiti, Nepal, and Uganda; and additional scale up is required for at least one disease in the other countries. Facilitating scale up by the end of FY16, in order to achieve the global 2020 goals, is therefore a challenge. It is apparent that current global resource levels are insufficient—this is a key advocacy message for USAID and ENVISION to carry forward together.