A Great Worm

Dracunculiasis medinensis, or Guinea worm: the epitome of the unpleasant parasite. This is the worm that wriggles in your very flesh, with no diminutive size to excuse it from your revulsion and horror! Contemplate this serpent of the subcutaneous tissues, and tremble you mushy-entrailed, temperate climate-dwelling saps! Tremble! Now!

This worm is endemic in a large part of Africa, the broad band of sub-Saharan semi-desert regions that includes such vast countries as Chad, Mauritania, Mali, Ethiopia, coastal west African countries, and ‘the’ Sudan. It is caught by drinking water contaminated with the vector copepod crustacean. Worm larvae burrow their way from the stomach into various body cavities where they mature and mate. Once fertilized, the female will burrow onward, outward, into the fatty tissue just below the skin, usually near the extremities, usually on a leg. She is the length of your arm. Worms may be seen or felt as they migrate under the skin. They may get lost on the way to the leg and end up in the joints, brain or even the eyes, resulting in arthritis, brain abscess, blindness. The foreign tissue stimulates the immune system, and the patient will often have itchy rashes, hives, fever and vomiting. Once settled the adult female will work her uterus to the surface of the skin, where it will protrude slightly, waiting to release thousands of eggs on contact with water.

Unpleasantly, a painful, very itchy blister will form around the worm tip, which will burst and become an ulcer infected with various bacteria. Interestingly, the tremendous itching of the ulcer is relieved by immersing the limb in water.

And the treatment? Antibiotics help loosen its grip on the flesh. Then, you make an incision in the skin over the worm’s midriff, and catch a loop out, passing a short rod underneath so it won’t slip back, or tempt out the tip by immersing the leg in water and lassoing it with a piece of cotton thread. Then, gradually, delicately (so as not to break it) the worm is ‘turned’ – one twist of the rod each day until its hold is sufficiently diminished for the remainder to be eased out in one long pull.

There is a nice picture here and info in English here

For adventures with ticks, snakes, disease and tropical nastiness generally, without having to leave the safety of anything at all (except sleep) may I recommend you read 'Congo Journey' by Redmond O'Hanlon, or indeed 'In Trouble Again'. Africa and S America, respectively.