What is the definition of Lymphatic Filariasis?
Lymphatic filariasis is a parasitic disease caused by microscopic, thread-like worms that only live in the human lymph system, which maintains the body's fluid balance and fights infections. It is spread from person to person by mosquitoes. Most infected people are asymptomatic and never develop clinical symptoms. A small percentage of people develop lymphedema, which may affect the legs, arms, breasts, and genitalia; bacterial infections that cause hardening and thickening of the skin, called elephantiasis; hydrocele (swelling of the scrotum) in men; and pulmonary tropical eosinophilia syndrome. Treatment may include a yearly dose of medicine, called diethylcarbamazine (DEC); while this drug does not kill all of the adult worms, it prevents infected people from giving the disease to someone else.
What are the alternative names for Lymphatic Filariasis?
- Wuchereria Bancrofti infection
- Filarial elephantiasis
- Malayi tropical eosinphilia
- Bancroftian filariasis
What are the current treatments for Lymphatic Filariasis?
The main treatment for this disorder is the use of major anti-parasiticide drugs; examples of these include ivermectin, albendazole, and diethylcarbamazine (DEC). These drugs work to get rid of the larval worm, to inhibit reproduction of the adult worm, or to kill the adult worm. For individuals who are actively infected with the filarial parasite, DEC is typically the drug of choice in the United States. The drug kills the microfilaria and some of the adult worms. DEC has been used world-wide for more than 50 years. Because this infection is rare in the U.S., the drug is no longer approved by the Food and Drug Administration (FDA) and cannot be sold in the United.States. Physicians can typically obtain the medication from the CDC after confirmed positive lab results. DEC is generally well tolerated. Side effects are in general limited and depend on the number of microfilariae in the blood. The most common side effects are dizziness, nausea, fever, headache, or pain in muscles or joints. Another treatment option, ivermectin, kills only the microfilariae.
For individuals with clinical symptoms of the condition, treatment depends on the signs and symptoms the affected individual has. Lymphedema and elephantiasis are not typically indications for DEC treatment because most people with lymphedema are not actively infected with the filarial parasite. To prevent the lymphedema from getting worse, individuals should ask their physician for a referral to a lymphedema therapist so they can be informed about some basic principles of care such as hygiene, exercise and treatment of wounds. Men with hydrocele (abnormal accumulation of fluid in the scrotum) may have evidence of active infection, but typically do not improve clinically following treatment with DEC. The treatment for hydrocele is surgery. Surgery may also be performed to remove the remains of adult worms and calcifications developing around them. Treatment of elephantiasis of the legs usually consists of elevation and support from elastic stockings.
In the tropical areas of the world, mosquito control is an important part of prevention of filariasis. Filariasis is usually a self-limited disease unless reinfection occurs. Therefore some cases, especially those brought into temperate regions of the world (i.e., North America), may be left untreated because there is no danger of spreading the disease.