Lymphatic Filariasis (Elephantiasis)

What is elephantiasis?

Elephantiasis (pronounced “eh-luh-fuhn-TAI-uh-suhs”) is a type of infectious disease that causes skin thickening and (in some cases) disfigurement. You get elephantiasis through tiny parasitic worms (filarial worms) that infect your lymphatic system. These parasites block your lymphatic capillaries and cause fluid (lymph) to accumulate.

People with elephantiasis may also develop inflammation, swelling and fever. Without treatment, elephantiasis can cause health complications.

Another name for elephantiasis is lymphatic filariasis (pronounced “fil-ur-AI-uh-suhs”).

How common is elephantiasis (lymphatic filariasis)?

About 120 million people worldwide — 1.5% of the world’s population — have a lymphatic filariasis infection. The condition is most common in tropical climates. Countries in Asia, Africa and South America have higher cases.

Elephantiasis is rare in North America. The worms that cause it don’t live in the United States.

It’s rare to get an elephantiasis infection during a short visit to one of these countries. You’re more likely to get the condition if you stay in a high-risk area for months or years.

What are the symptoms of elephantiasis?

About 2 in every 3 people who have lymphatic filariasis don’t have severe symptoms. But filariasis usually leads to a weakened immune system.

Some people may experience:

• Inflammation (due to an overactivated immune system).
• Lymphedema (fluid buildup in your lymphatic system).
• Hydrocele (swelling and fluid buildup in your scrotum).
• Edema (swelling and fluid buildup in tissues throughout your body).

Elephantiasis can affect various parts of the body, including your:

• Arms.
• Legs.
• Breasts.
• Scrotum.
• Penis.
• Vulva.
• Face.

What causes elephantiasis?

Elephantiasis can occur when a person has filariasis — a parasitic infection by a type of roundworm. Tiny worms, too small to see with the naked eye, invade your body. Under a microscope, the filarial worms look like threads.

There are several types of filarial worms:

• Wuchereria bancrofti causes 9 out of 10 infections.
• Brugia malayi leads to most of the remaining cases of the disease.
• Brugia timori can also cause infection.

How does lymphatic filariasis spread?

Lymphatic filariasis spreads through mosquito bites. When a mosquito bites someone who has filariasis, the filarial worms in the person’s blood infect the mosquito. Then, when the infected mosquito bites another person, the worms pass into that person’s bloodstream.

In general, a person won’t get filariasis from a single mosquito bite. It usually takes repeated mosquito bites over several months (or even years) for a person to get the condition.

When these worms enter your bloodstream, they travel to your lymphatic system. There, they grow into adult worms. The adult worms stay alive for up to seven years. The filarial worms reproduce and release millions of worms into your bloodstream.

What are the complications of elephantiasis?

Over time, damage to your lymphatic system may make it difficult for your body to fight infections. Because of this lowered immune response, you may develop:

• Frequent bacterial infections.
• Thickened skin and fluid retention, leading to painful, swollen and enlarged body parts.
• Tropical pulmonary eosinophilia syndrome — an increase in white blood cells that causes coughing and difficulty breathing.

How is elephantiasis diagnosed?

To diagnose elephantiasis, healthcare providers need to examine a blood sample. They may use:

• Microscopic blood test. Providers may view your blood sample under a microscope. The microscope allows them to see if your blood has any filarial worms. Filarial worms are nocturnally periodic, meaning they only move in your blood at nighttime. Because of this, you may need to get your blood drawn at night.
• Antibody test. Providers may measure your blood sample for antibodies. Antibodies are organisms that your body creates in response to an infection. You can have this test during the day.

How is elephantiasis treated?

Your treatment plan varies depending on what symptoms you have and how severe they are. In general, elephantiasis treatment may include:

• Antiparasitic drugs. You may take medications like ivermectin (Stromectol®), diethylcarbamazine (Hetrazan®) or albendazole (Albenza®). These drugs destroy the adult worms in your blood or keep them from reproducing. Taking antiparasitic drugs can also prevent passing the infection to someone else. Because the worms may still live in your body, you take these medications once a year for a few weeks at a time.
• Surgery. You may have surgery to remove dead worms from your bloodstream. If filariasis has caused hydrocele, you may also have surgery to relieve fluid buildup in your scrotum.
• Elephantiasis management. Your healthcare provider may also recommend strategies to manage swelling, like elevation or compression garments.

Side effects of elephantiasis treatment

If you’re taking filariasis medications, you need careful monitoring from a healthcare provider. Antiparasitic drugs can lead to severe side effects, including:

• Dizziness.
• Fever.
• Headache.
• Muscle or joint pain.
• Nausea.

Is there a cure for lymphatic filariasis?

There isn’t a vaccine or cure for lymphatic filariasis. Medication can kill many of the worms and keep you from spreading the infection to someone else. Treatment can also reduce your symptoms.

Can elephantiasis be prevented?

The best way to prevent elephantiasis is to avoid mosquito bites, particularly in tropical areas. If you live in or travel to places where a filariasis infection is possible, take the following steps to prevent mosquito bites:

• Sleep under a mosquito net.
• Use insect repellent on exposed skin, especially at night.
• Wear long pants and long sleeves.

In parts of the world where filariasis is common, the World Health Organization (WHO) recommends treating whole regions with preventive chemotherapy. With this prevention strategy, people at risk of infection take an annual dose of specific chemotherapy drugs.

The medications have a small effect on adult worms but can keep younger worms from reproducing. They can also prevent the parasites from spreading to mosquitoes.

What can I expect if I have elephantiasis?

People with elephantiasis often experience negative social impacts. If they have very visible, severe symptoms like extreme swelling, they may experience social stigma. Chronic swelling or pain may also impact a person’s ability to work. While elephantiasis has no cure, you can manage the condition and reduce its symptoms.

When should I see my healthcare provider?

If you develop unexplained swelling or thickening of your skin — particularly in your arms, legs, breasts, scrotum or vulva — let a healthcare provider know. They can run tests to confirm or rule out a diagnosis.

What questions should I ask my doctor?

You may also want to ask your healthcare provider:

• What’s the most likely cause of elephantiasis?
• How can I manage symptoms related to elephantiasis?
• What treatment do you recommend for elephantiasis?
• Are there any side effects of treatment?
• What are the chances that an infection will return after treatment?
• How can I prevent elephantiasis?

How can I manage lymphedema symptoms?

Even if medication kills the filarial worms, you can still develop lymphedema. To manage lymphedema symptoms, you can:

• Disinfect and cover any wounds.
• Elevate (raise) swollen arms or legs.
• Increase your activity level. (This can encourage the flow of lymphatic fluid.)
• Wash and dry swollen areas of your body daily.
• Wear properly fitted shoes to reduce your risk of falling and getting injured.