Symptoms of Loiasis

Key points

  • The most common symptoms of loiasis are itchy skin swellings and eye worms.
  • Joint pain, fatigue, and itching across the body are less frequent.
Anterior view of Loa loa filaria.


As with other diseases caused by parasitic worms, many people who are infected with Loa loa never develop symptoms. But in those who do, the main symptoms are

  • Itchy, non-painful body swelling that comes and goes, known as Calabar swelling.
  • Eye worms, which crawl across the surface of the eye.
  • Worms may be visible crawling under the skin.

Calabar swelling can show up anywhere, although it's more likely to happen near joints.

Although eye worms can be scary, they last a short time—often just a few hours—and cause little damage to the eye.

Less common symptoms include

  • Itching all over your body
  • Muscle pain and joint pain
  • Feeling weak and tired (fatigue)

In rare cases, people with loiasis may experience

  • Painful swellings of lymph glands
  • Swollen scrotum, in men
  • Inflammation of parts of the lungs
  • Fluid collection around the lung
  • Scarring of heart muscle
  • Kidney damage, if infection continues for many years