Disease Caused by Filarial Worm

In this article we will discuss about:- 1. Mode of Infection of Filarial Disease 2. Symptoms of Filarial Disease 3. Prevention 4. Treatment.

Mode of Infection of Filarial Disease:

Filarial disease is usually transmitted to man through mosquito biting. The disease can be accidentally transmitted through blood transfusion, when the donor is infected with microfilariae. The entry of the infective stage, microfilaria in the human body is not through direct inoculation into the blood stream by the mosquito during its blood meal.

Instead, when a mosquito with infective larvae in its proboscis feeds on a person, the larvae get deposited usual­ly in pairs on the skin near the puncture site. The larvae then enter through the wound or puncture. Subsequently they reach the lymphatic channels and settle down at some spots like scrotal sac or inguinal lymph nodes or abdominal lymphatics and begin to develop into an adult worm within a period of 5-18 months.

Symptoms of Filarial Disease:

i. Filarial disease is accompanied with fever and headache.

ii. Owing to virulent filarial infection, the microfilariae block the passage of lymph-gland and as a result lymph cannot go back to the circulatory system, causes tremendous unequal swelling of scrotum, legs, mammary glands etc. This condition of swelling is known as elephantiasis.

iii. The skin of the affected region becomes rough and fissured.

iv. In extreme cases, the connective tissue of the affected parts becomes abnormal when the condition becomes further compli­cated.

Prevention of Filarial Disease:

The filarial disease could be prevented by adopting several prophy­lactic measures:

i. Eradication of the vector mosquito by using allethrin or other insecticides.

ii. Destruction of mosquito larvae in the breeding ground can be done by using various larvae ides.

iii. Sterilization of male mosquito .should be done by artificial means.

iv. Protection against mosquito bite by using various devices like mosquito-net, mos­quito repellent mat or cream etc.

v. As a measure of biological control mos­quito larvae eating fishes like Gambusia. Gold fish etc. may be cultured in the breeding habit of mosquito.

vi. Reducing the rate of infection amongst hosts by preventing them from biting the infected individuals.

Treatment of Filarial Disease:

i. No proper or satisfactory treatment is yet known.

ii. Ivermectin (Mectizan) is very effective against the microfilariae, a single dose is being able to reduce skin micro-filarial counts to undetectable levels within seven days.

iii. Treatment of filaria patient with proper drugs, viz. Mel. W (an arsenical prepa­ration) on adult worms has given encoura­ging result; Hetrazan compounds on micro-filarial worm and paramelaminyl phenyl stibonate on infective larva and immature adult worm etc. that are used to make the blood free of microfilariae.

iv. Edematous limbs are sometimes success­fully treated by applying pressure ban­dages, which force the lymph out of the swollen area of filarial patient.

v. Surgical removal of elephantoid tissue is often possible.