With the emergence of the worm's head, the blister grows and becomes erythematous at its periphery. Edema occurs around the site, and inflammation of the papule causes further pruritus and burning pain. After a period of time, usually lasting a few days but possibly enduring as long as 2 weeks, the blister erupts, and the worm releases a collection of larvae-containing fluid. The swelling and pain often are markedly decreased after the blister is opened. At this point, an ulcer forms around the blister site as the adult worm continues to emerge.
Definitive diagnosis is made when the head of the worm is identified within the ulcer.
As noted, the ulcer tends to become secondarily infected. No other particular physical findings are noted commonly, although some degree of lymphadenopathy may be found at any stage of the illness. This, of course, requires a fresh-water environment, leading to water ingestion as the only identified mode of transmission. Differential commonly will show eosinophilia. The most common practice to treat dracunculiasis remains wrapping around a stick.