Red Dracunculus medinensis.

Two instances of the emergence of a bright-red worm from humans in Pakistan are described. A 25-year-old man and a 26-year-old woman, unrelated and living in separate households, were observed in 1987 and 1988, respectively, to have emergent worms typical in size and location for Guinea worm disease, except for the color of the worms. The posterior end of 1 worm was recovered and appeared to be a female Dracunculus medinensis. Histologic sections provided insufficient information to determine the cause of the red color, although we could exclude blood as the cause.