Filariasis is a tropical disease caused by mosquitoes that affects over 12 Crore people worldwide. It infects the body through tiny filarial worms. The larval form of the parasite transmits the disease to humans by the bite of a mosquito.These larvae worms reside in the human lymph system where they grow to become adults and live in the body for somewhere between 6-8 years, mating and giving birth to millions of larvae.

Filariasis is mostly caused by two species of worms - Wuchereria bancrofti and Brugia malayi. Filariasis is also known by the following names Bancroftian Filariasis, Filarial Elephantiasis, Filariasis Malayi, Malayi Tropical Eosinophilia, Wuchereriasis

WHAT ARE THE SYMPTOMS OF FILARIASIS? 

Some of the common causes of filariasis are mentioned below, however some people with filariasis might have no symptoms at all.

• Swelling of the legs and genitals and various parts of the body 

• Severe inflammation of the skin, lymphatic vessels and lymph nodes

• High temperatures, shaking chills, body aches

• Excessive amounts of fluid accumulation in arms and/or legs 

DIAGNOSIS AND TREATMENT 

Diagnosis: The diagnosis of filariasis requires examination of a blood smear for the presence of the larval roundworm W. bancrofti or B. malayi. Since the number of parasites in the blood is higher during the night, blood samples are best obtained at night. When parasites are not found in the blood, the adult worms may occasionally be found in a lymph node sample from an infected individual.

Treatment: Treatment in the earlier stages can be through medication to fight off the infection and surgical procedures may be required for later chronic stages. Progressively increasing doses of any one of the major anti-parasiticide drugs is the treatment for the disorder. The elimination of adult worms must be undertaken with care because high concentration of dead worms in the lymph or blood can provoke dangerous allergic reactions and abscesses.

Surgery may be used to treat some people with filariasis who develop an abnormal accumulation of fluid in the scrotum. 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.

IMPORTANT INFORMATION 

1. Most of the infections are asymptomatic, but if the state worsens to become acute or chronic, it will lead to an onset of swelling which gets very painful, eventually causing permanent disability.

2. Currently there are no vaccines available for filariasis, so preventing mosquito bite is the best form of defense. Preventive measures for the same are: 

• Avoiding outdoor activity at dusk or dawn 

• Sleeping inside a mosquito net

• Wearing long sleeved shirts and trousers