The neglected tropical diseases (NTDs) affect more than 1 billion of the poorest and most marginalized people of the world. These infections are a consequence of the environmental and socioeconomic conditions in which the poor live, and the ill health and disability they cause are a primary factor locking the poor into poverty. They are diseases of the most neglected people who live in countries that lack the basic resources to control them. Yet this chapter demonstrates that the tools to end this neglect already exist, and that there are compelling economic arguments that ending these diseases would be one of the most cost-effective of global public health programs.

The NTD concept was developed to draw attention to this opportunity that was overlooked by the Millennium Development Goals (MDGs). At least 18 diseases are recognized as NTDs by World Health Assembly resolutions; the latest addition is mycetoma (WHO 2013, 2016). The World Health Organization (WHO) has set specific targets for control, elimination, and eradication of a subset of these diseases (table 17.1). These are the NTDs that we focus on in this chapter. The end of NTDs is now firmly embedded within the Sustainable Development Goals (SDGs) for 2030, under target 3.3, reflecting the promise to “leave no one behind.”

This chapter reaffirms the case that NTDs account for a significant and unfairly distributed global disease burden, cost-effective interventions exist to reduce that burden, these interventions are affordable, and they are good investments in universal health coverage and social protection. It builds on the second edition of the Disease Control Priorities (DCP2) project (Hotez and others 2006) with new data and analysis. It also takes into account new strategies and tools that have been introduced since 2006 and the increasingly ambitious elimination and eradication targets for individual diseases that have emerged since 2012, including the unprecedented donation by the pharmaceutical industry under the London Declaration of more than a billion medicines annually to treat nine of the most important NTDs. Finally, it helps provide a longer-term perspective on SDG target 3.3 and the 2030 goals.

This chapter is structured around three key NTD interventions, rather than individual NTDs, in recognition of the increasingly integrated delivery of interventions to the poorest, most remote, and otherwise most marginalized communities of the world. These interventions are as follows:

1. Preventive chemotherapy by mass drug administration

2. Innovative and intensified disease management

3. Vector ecology and management.

For simplicity of analysis, we focus on a subset of the NTDs recognized by the WHO. We do not provide a full analysis of veterinary public health interventions against zoonotic NTDs or of water, sanitation, and hygiene (WASH). These conditions are beyond the scope of this chapter, but WASH is addressed in chapter 9 in volume 7 of the third edition of Disease Control Priorities (Hutton and Chase 2017). Chapter 13 in volume 8 (Bundy and others 2017) discusses mass deworming programs, and chapter 29 (Ahuja and others 2017) in volume 8 analyzes the economics of such programs.