Filariasis
There are two species of filarid worms in the Philippines and these are:
1. Wuchereria bancrofti
2. Brugia malayi.
These filarid worms will parasitize the lymphatic system of man after being bitten by an infected mosquito. Once man is bitten, the third stage larvae is deposited in the skin, Then, these larvae will pass the lymphatics and grow to maturity in 4 to 6 months in the case of B. malayi and 12 to 18 months in W. bancrofti.
Clinically, within a few weeks of the infection, there is lymphangitis and lymphadenitis of the involved lymph vessel as a reaction to trapped worms and their metabolites. These manifestations may subside but may recur on and off for years. If there is no treatment and there is re-infection, then chronic stage may happen which may lead to complete obstruction of the lymphatics due to the death of the worms and with tissue reactions, elephantiasis may occur.
Filariasis is common in the Bicol peninsula, Samar, Leyte, Mindanao, Palawan and Northeastern Luzon. So, to avoid filariasis, one must protect against mosquito bites and mosquito control in known endemic areas must be instituted.