What are neglected tropical diseases?

NTDs are a group of 20 diverse infectious diseases that predominantly affect the world's poorest people in tropical and subtropical regions. They include parasitic diseases (lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminths, guinea worm), bacterial diseases (leprosy, yaws, Buruli ulcer, trachoma), viral diseases (rabies, dengue) and fungal diseases. They are "neglected" because they receive minimal research funding and public attention relative to their enormous burden.

How many people are affected by NTDs?

An estimated 1.7 billion people in 149 countries require NTD prevention, control or treatment interventions. The most affected regions are Sub-Saharan Africa, South and Southeast Asia, and Latin America. Critically, NTDs affect the same communities as poverty, poor WASH access and malnutrition — creating a "poverty trap" where disease perpetuates poverty.

What is preventive chemotherapy?

Preventive chemotherapy (PC) — mass drug administration (MDA) of donated medicines to at-risk populations — is the most cost-effective NTD intervention. Five major pharmaceutical companies donate over 1 billion treatments annually (ivermectin, albendazole, mebendazole, praziquantel, DEC, azithromycin). PC targets 5 diseases simultaneously: lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminths and trachoma.

What is the WHO NTD Roadmap 2021-2030?

WHO's NTD Roadmap targets: eradicating 2 diseases (guinea worm, yaws); eliminating 12 diseases as public health problems in the countries where they occur; reducing 90% of the number of people requiring NTD interventions globally. It emphasises integration, country ownership and primary health care system strengthening. Progress is measured annually through the NTD country profiles.

Is guinea worm eradication succeeding?

Yes — guinea worm (dracunculiasis) is on the verge of becoming only the second human disease ever eradicated (after smallpox). Cases fell from 3.5 million in 1986 to fewer than 15 in 2023 — entirely through water filtration, education and case containment, with no vaccine or medicine. The Carter Center leads the eradication campaign. The primary challenge now is animal transmission (dogs, monkeys) in Chad and Cameroon.

What is lymphatic filariasis?

Lymphatic filariasis (LF) — the cause of "elephantiasis" — is a mosquito-borne parasitic disease causing lymphoedema (massive limb swelling), hydrocele (scrotal swelling) and social stigma. It affects approximately 882 million people in 44 countries at risk. Annual MDA with ivermectin + albendazole (or DEC) can interrupt transmission. Morbidity management for existing lymphoedema (hygiene, compression, exercise) reduces suffering.

What is onchocerciasis (river blindness)?

Onchocerciasis is caused by Onchocerca volvulus, transmitted by Simulium blackflies breeding near fast-flowing rivers. Chronic infection causes severe itching, skin damage and progressive visual loss — the world's second leading infectious cause of blindness. Annual ivermectin MDA (donated by Merck since 1987) has successfully controlled or eliminated onchocerciasis across most of Africa and Latin America.

What is schistosomiasis?

Schistosomiasis — from freshwater contact with cercariae released by infected snails — affects approximately 250 million people in 78 countries. Chronic infection causes bladder cancer, liver fibrosis, portal hypertension, anaemia and cognitive impairment in children. Treatment is with praziquantel (single dose). WASH improvement and snail control reduce transmission. Sub-Saharan Africa bears 90% of the global burden.

What is the drug donation model?

Five pharmaceutical companies donate over 1 billion NTD medicine treatments per year to WHO-coordinated programmes: Merck (ivermectin for onchocerciasis and LF), GSK (albendazole for LF and STHs), Eisai (DEC for LF), Pfizer (azithromycin for trachoma) and Bayer (nifurtimox for sleeping sickness). This unique public-private partnership has enabled the world's largest preventive medicine programme and is a model for access to medicines in LMICs.

Leprosy (Hansen's disease) — from Mycobacterium leprae — causes skin lesions, nerve damage and disability. Stigma persists despite multi-drug therapy (MDT) being fully curative. WHO targets "zero leprosy" — zero new cases, zero disability in children, zero discrimination. Approximately 200,000 new cases are still diagnosed annually. India, Brazil and Indonesia account for 80% of global cases.

What is snakebite as an NTD?

Snakebite envenomation — added to the WHO NTD list in 2017 — kills approximately 94,000-138,000 people per year (primarily in South Asia and Sub-Saharan Africa) and leaves 400,000 with permanent disability (amputations, blindness). It predominantly affects rural farmers and children. Access to safe, effective antivenom is the primary treatment challenge.

How does GMJ News cover NTDs?

GMJ News tracks WHO NTD Roadmap progress, guinea worm eradication campaign milestones, drug donation programme updates and the poverty-NTD nexus. NTDs are directly relevant to global health equity priorities covered by the Georgian Medical Journal's international health section.

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Neglected Tropical Diseases

GMJ News knowledge hub · last reviewed September 2026 · Georgian Medical Journal

Summary Statistics Glossary GMJ news FAQ Documents Organizations Research

Neglected tropical diseases (NTDs) are a diverse group of 20 conditions that predominantly affect the world's poorest populations: 1.7 billion people in 149 countries require NTD interventions, and the diseases cause profound disability, stigma, poverty and preventable death (WHO). The WHO NTD Roadmap 2021-2030 targets disease-specific elimination and eradication goals using preventive chemotherapy, vector control, WASH and case management. NTDs are diseases of poverty — their elimination is inseparable from progress toward SDG 1 (no poverty), SDG 3 (health) and SDG 6 (clean water).

Key messages

1.7 billion people affected

20 neglected tropical diseases (NTDs) affect 1.7 billion people in 149 countries — predominantly the world's poorest communities — causing immense suffering, disability and poverty. NTDs are strongly correlated with extreme poverty (WHO NTD Roadmap 2021-2030).

Treatable with cheap drugs

Many NTDs can be controlled or eliminated through preventive chemotherapy — mass drug administration (MDA) of donated medicines (ivermectin, albendazole, praziquantel, azithromycin) to at-risk populations. More than 1 billion treatments are donated annually.

WHO NTD Roadmap 2021-2030

The WHO NTD Roadmap 2021-2030 targets: eradicating 2 diseases; eliminating 12 diseases as public health problems; and reducing the number requiring NTD interventions by 90% globally by 2030. These are the most ambitious NTD targets ever set.

Poverty trap

NTDs cause disability, disfigurement and stigma that impede education and economic participation — keeping affected communities in poverty. Eliminating NTDs is inseparable from breaking the poverty cycle and achieving SDGs 1 and 10 (inequality reduction).

Drug donations

Major pharmaceutical companies donate hundreds of millions of doses of NTD medicines annually — creating a unique public-private partnership model. Merck (mectizan/ivermectin), GSK (albendazole), Pfizer (azithromycin) and Bayer are key partners.

Eradication possible for two

Guinea worm disease (dracunculiasis) is on the verge of eradication — cases fell from 3.5 million in 1986 to fewer than 15 in 2023. Yaws is targeted for eradication by 2030 with single-dose azithromycin.

Key statistics

1.7B

people requiring NTD interventions

WHO 2021

149

countries with endemic NTDs

WHO

1B+

treatments donated annually

WHO/partners

diseases in the NTD group

WHO

<15

guinea worm cases in 2023

Carter Center/WHO

2021-2030

WHO NTD Roadmap period

WHO

NTDs eliminated or eradicated 2012-2030 — WHO NTD Roadmap milestones

Source: WHO NTD Roadmap 2021-2030. Countries achieving elimination as public health problem targets.

Glossary of key terms

Neglected tropical diseases (NTDs)
WHOA diverse group of 20 infectious conditions affecting 1.7 billion people in 149 countries — primarily in tropical and subtropical areas. They are "neglected" because they receive far less research and development investment relative to their burden.

Preventive chemotherapy (PC)
WHOMass drug administration (MDA) of safe, donated medicines to at-risk populations regardless of individual infection status. The most cost-effective NTD control strategy — used for lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminths and trachoma.

Lymphatic filariasis
WHOA mosquito-borne parasitic disease causing lymphoedema (elephantiasis) and hydrocele — responsible for the world's second leading cause of long-term disability after mental disorders. Targeted for elimination through annual MDA with ivermectin + albendazole or DEC.

Onchocerciasis (river blindness)
WHOA parasitic disease transmitted by blackflies breeding in fast-flowing rivers — the world's second leading infectious cause of blindness. Controlled through annual ivermectin MDA and vector control. Elimination achieved in several Latin American countries.

Guinea worm disease
WHO/Carter CenterDracunculiasis — caused by a waterborne worm — is on the verge of eradication: cases fell from 3.5 million in 1986 to fewer than 15 in 2023 through water filtration and containment, with no medicine or vaccine.

Schistosomiasis
WHOA parasitic flatworm infection from freshwater contact — causing bladder cancer, liver fibrosis and anaemia. Affects approximately 250 million people in 78 countries. Controlled through praziquantel MDA.