(1) General. Filariasis is a diseased state caused by the presence of filariae
within the body. The infection is caused by filarial worms that stay in the lymphatic
system and produce recurrent lymphangitis with obstruction and fibrosis. There are two
possible filarial nematodes that cause filariasis. The transmission of the infective larvae
of the Brugia malayi nematode to humans is due to a bite from certain Mansonia or
Anopheles mosquito. These mosquitoes are found in south India, south China,
Southeast Asia and Ceylon. On the Pacific Islands and in the tropics and subtropics of
both hemispheres, the Wuchereria bancrofti nematode (found only in humans) is
transmitted from human to human by certain Culex and Aedes mosquitoes.
(2) Signs and symptoms. At the beginning of filariasis, there is
inflammation, but in later stages, it progresses to obstruction in the lymphatic system.
The victim experiences episodes of fever and the inflammatory lymphatitis and nodes
that flare up at irregular intervals.
(3) Treatment. For the febrile and local inflammatory occurrences, bed rest
is indicated. For secondary infections (abscesses over inflamed nodes), antibiotics
should be administered. A palliative measure used for orchitis (inflammation of the
testis), epididymitis (inflammation of the elongated cordlike structure along the posterior
border of the testis), and scrotal lymphedema, a suspensory bandaging may be used.
Mild edema of a limb may be treated with rest, elevation, and by an elastic stocking. In
cases of elephantiasis (inflammation and enlargement of the part), the surgical removal
of the breast, scrotum or vulva is easy and usually satisfactory. Limb elephantiasis is
not easy and meets with disappointing results. The drug of choice is
diethylcarbamazine which is given orally 3 times daily after meals for 21-28 days. The
dosage is usually 2 mg of citrate per body weight. The microfilaria are destroyed;
however, there is only limited action on the adult worms. If the victims leaves the
endemic area with only a mild case, his prognosis is good.