[Furuncular myiasis].

Abstract

Prior knowledge of foruncular myiasis in Africa and American specially México, is reviewed, leading to current criteria for definitive on of this disease. The Dermatobia genus, species hominis, are parasitic for man. Our cases belong to the latter. Epidemiological studies show the States of Tabasco, Chiapas and Campeche as most heavily affected, specially during the rainy season in which insects proliferate including vectors. Clinical studies confirmed five evolutionary stages of larvae. In the first stage larvae show a wide anterior and a narrow distal ends. The latter curls in. They show noticeable rings and reach up to 1 cm. in length. In the second stage, at 15 days, larvae resemble a segmented dagger. In the third stage, at 30 days, become ovate, showing rings and cyliae, the worms being white and soft. In the fourth stage, at 45 days, the worms are two cms. long and one cm. thick, the cyliae becoming more abundant and black. At 50 days structures suggesting wings appear. Adult Dermatobia are large flies, two cms. in length, with long extremities, a brown thorax, and a purplish blue abdomen, with a metallic sheen. Man becomes infested through arthropod bites or bathing in a pool larvae reach inside follicles, giving rise to erythema, papules and severe pruritus, Papules increase in size, infiltrate subcutaneous tissue, forming bluish red hard nodules, 1-2 cms. in length, which contain one or several larvae. From 10 to 60 days, their tops show an ecchymotic plaque which breaks down. The parasites come out usually dead. Besides pruritus symptoms include pain, a burning sensation, perception of larval motion.(ABSTRACT TRUNCATED AT 250 WORDS)