What is lymphatic filariasis?

Lymphatic filariasis is a serious disease, with millions of people globally at risk. It can cause a range of different unpleasant symptoms, but is frequently characterised by abnormal enlargement of body parts.

Hassana from Nigeria sits in her home. She has lymphatic filariasis and her left leg is visibly swollen.

Lymphatic filariasis is transmitted via mosquito bite. The infection is usually first acquired during childhood.

Lymphatic filariasis can result in an altered lymphatic system and the abnormal enlargement of body parts. This is painful and leads to permanent physical changes – a condition called lymphoedema – and is highly stigmatised. In men, the disease causes a condition called hydrocele, a form of lymphoedema that causes the scrotum to swell, leading to pain and disability.

It is one of a group of conditions known as neglected tropical diseases (NTDs). Once a person is infected, adult worms lodge in the body’s lymphatic vessels, affecting the lymphatic system. The worms can live for six to eight years, producing millions of larvae that circulate in the infected person’s blood.

The debilitating symptoms mean many people are unable to work, and children miss school to care for family members. The associated stigma can have a devastating impact on those affected, as well as their families and communities.

Watch our video to learn more about this painful disease.

120 million
people worldwide are infected with LF
40 million
people are incapacitated by the disease
885 million
people are currently at risk of LF

How is lymphatic filariasis treated?

A girl in Kenya receives her medication to protect against river blindness and lymphatic filariasis.


A combined dose of two medicines is given every year to people in high-risk areas by local volunteer community-directed distributors.

Ibrahim Hassan from Nigeria, who suffers from lymphatic filariasis.

Medical care

Although people suffering from advanced lymphatic filariasis cannot be cured, the symptoms can be eased through surgery and care.

A woman working in a science laboratory.


Research is undertaken to evaluate, inform and improve our programme strategies, helping to eliminate this disease more quickly and fairly.

What we’re doing

Sightsavers is fighting hard to eliminate lymphatic filariasis in the countries in which we work by 2030.

While river blindness is transmitted by the black fly and lymphatic filariasis by the mosquito, both diseases are caused by an infection of a filarial worm and often occur in the same places. Where they are co-endemic, Sightsavers coordinates treatments for these two diseases using Mectizan® tablets, donated by pharmaceutical company Merck Sharpe & Dohme (MSD), and albendazole tablets, donated by GlaxoSmithKline.

In countries where river blindness in not co-endemic, lymphatic filariasis is treated using diethylcarbamazine, produced by Eisai, and albendazole tablets, donated by GlaxoSmithKline.

In 2019, we provided more than 50 million treatments for LF worldwide. We also trained more than 269,000 local volunteers to distribute medication via mass drug administration to treat a range of neglected tropical diseases, including lymphatic filariasis.

Although people suffering from advanced lymphoedema cannot be cured, the symptoms can be eased through surgery and care. Sightsavers works with WASH (water, sanitation and hygiene) organisations to help households access clean water and facilities, so people can clean their affected limbs and care for their skin with clean water and soap. Symptoms can also be helped by elevating limbs and by wearing footwear. Hydrocele can be cured through surgery, transforming the lives of men affected.

A nurse helps a woman learn how to care for her swollen limb caused by lymphatic filariasis.

Caring for patients in DRC

An estimated 42 million people in the Democratic Republic of Congo need treatment for lymphatic filariasis. Find out how Sightsavers is working to protect communities.

Read more

Find out about other diseases we treat

Neglected tropical diseases

More about lymphatic filariasis

A man is measured against a dole pole to determine how much lymphatic filariasis treatment he needs.

Sightsavers welcomes new WHO NTD 2030 road map

Sightsavers welcomes WHO’s new NTD 2030 road map, which sets out global targets and milestones for 2030 in order to prevent, control, eliminate and eradicate a diverse set of 20 diseases and disease groups.

November 2020
A community volunteer distributed treatment to protect against neglected tropical diseases to a woman.

Health programme exceeds several first-year targets

A Sightsavers-led programme in Africa has surpassed several of its first-year targets as it delivers more than 127 million drug treatments for five debilitating neglected tropical diseases (NTDs).

September 2020
Sightsavers from the field

Working together to tackle NTDs in Liberia

In the first year of the programme, the Ascend West and Central Africa partners have supported health workers and volunteers to deliver mass treatment campaigns that will help tackle high rates of neglected tropical diseases (NTDs) in Liberia.

August 2020

Learn how we’re fighting disease