Illness caused by infection with a parasite called a filarial worm.

Filariasis is caused by parasites that are spread between people by biting flies or mosquitoes. The illness a person gets depends on the specific parasite. Untreated, some illnesses caused by these parasites can cause chronic problems.

Filariasis symptoms depend on the type of parasite infection. Some infections may cause a cough, fever and wheezing. Filariasis symptoms also can include skin reactions such as bumps, rashes or swelling. Eye symptoms include inflammation that can lead to blindness without treatment. Other filariasis symptoms include painful swelling of the legs and genitals.

Filariasis is treated with medicines that target parasites, called anti-parasitics.