What
Lymphatic filariasis (LF) is a deforming and disabling disease caused by an infection with threadlike nematode worms and transmitted via bites of infected mosquitos.
Who
Lymphatic filariasis affects over 120 million people, and approximately 800 million people remain at risk for the infection.
Where
Seventy-two countries, mostly in Asia and Africa
Symptoms
While many people with lymphatic filariasis infections have no symptoms, damage to lymphatic vessels caused by filarial worms and the body’s inflammatory responses can lead to lymphedema with elephantiasis (severe swelling and disfigurement of extremities) and to the accumulation of fluid in the scrotum (known as hydrocele) of men who are infected. These conditions are disabling and associated with social stigma.
DOLF Project’s contributions
The DOLF project has conducted important community mass drug administration (MDA) and clinical trials on lymphatic filariasis in recent years with colleagues in many endemic countries. These studies have shown that:
- Semiannual (twice per year) MDA is no more effective for lymphatic filariasis than annual MDA if high treatment coverage can be achieved.
- MDA with albendazole alone is a viable strategy for LF elimination in areas where ivermectin cannot be safely used because of coendemic loiasis.
- Triple-drug treatment with ivermectin, diethylcarbamazine (DEC) and albendazole — together referred to as IDA — is well tolerated and more effective for clearing filarial parasites from the blood than treatment with DEC plus albendazole. Ongoing studies are exploring the value of other combination treatments for LF.
- Results from our studies have helped change treatment recommendations and suggest a need for new methods to monitor progress toward LF elimination.
Additional information
The Global Programme to Eliminate Lymphatic Filariasis (GPELF) aims to eliminate the disease by 2030. GPELF is the largest public health intervention for an infectious disease implemented to date based on mass treatment: 8.6 billion doses of antifilarial medications were distributed in endemic countries via mass drug administration (MDA) programs between 2000 and 2020. These treatments have cured tens of millions of infections, prevented tens of millions of cases of filarial disease, and reduced transmission. While GPELF has reduced the number of LF cases in the world by about 50%, approximately 800 million people remain at risk for the infection, mostly in Asia and Africa. Despite significant progress, more time and better tools and strategies are needed to achieve global LF elimination.
Learn more about lymphatic filariasis from the Centers for Disease Control and Prevention and World Health Organization.