What are neglected tropical diseases?
Neglected tropical diseases (NTDs) are a group of communicable diseases widespread in tropical and subtropical regions. They’re caused by various pathogens (viruses, bacteria, parasites, fungi, or toxins) and have devastating health, social, and economic consequences. They affect one and a half billion people worldwide and cost developing economies billions of dollars each year.
NTDs mainly occur in rural areas, conflict zones, and hard-to-reach regions. They thrive in areas degraded by climate change and where access to clean water and sanitation is limited. They typically affect regions where quality healthcare isn’t available, making poor populations particularly vulnerable to these diseases. The African continent bears 40% of the global NTD burden.
Major progress has been made in the fight against NTDs in recent years. Hundreds of millions of at-risk people are treated and cared for annually. By the end of 2025, 58 countries had eliminated at least one NTD, and several have been recognized by WHO as having eliminated 2, 3, or 4 conditions.
However, these diseases remain “neglected” because they’re virtually absent from global health action. They receive very limited resources and are almost ignored by international funding bodies.
OPC’s action against neglected tropical diseases
Among the 20 diseases identified by WHO, OPC focuses on trachoma, onchocerciasis, schistosomiasis, lymphatic filariasis, and soil-transmitted helminthiases—two of which, trachoma and onchocerciasis, represent the two leading causes of infectious blindness worldwide. These five diseases can be fought through large-scale distribution of proven medications.
OPC’s approach involves helping countries map the disease, obtain drug donations, distribute them and train communities in distribution, and monitor and evaluate program performance and impact. OPC also works with local stakeholders to raise community awareness about hygiene and advocates for improved access to clean water and sanitation in individual homes and common spaces to limit NTD exposure risk.
Through OPC’s programs, millions of people—especially those living in the most vulnerable communities—have access to sight-restoring surgeries and receive the treatments they need to prevent the spread of neglected tropical diseases.