Dracunculiasis is also called guinea worm disease (GWD), is an infection by the guinea worm. A person becomes infected when they drink water that contains water fleas infected with guinea worm larvae. Initially there are no symptoms. About one year later, the person develops a painful burning feeling as the female worm forms a blister in the skin, usually on the lower limb.The worm then comes out of the skin over the course of a few weeks. During this time, it may be difficult to walk or work. It is very uncommon for the disease to cause death. Humans and dogs are the only known animals that guinea worms infect. The worm is about one to two millimeters wide and an adult female is 60 to 100 centimeters long (males are much shorter at 12–29 mm or 0.47–1.14 in). Outside of humans the eggs can survive up to three weeks, during which they must be eaten by water fleas to continue to develop. The larva inside water fleas may survive up to four months. Thus the disease must occur each year in humans to stay in an area. A diagnosis of the disease can usually be made based on the signs and symptoms of the disease.
In 2014 there were 126 cases of the disease reported. This is down from 3.5 million cases in 1986. It only exists in 4 countries in Africa, down from 20 countries in the 1980s. The country most affected is South Sudan. It will likely be the first parasitic disease to be globally eradicated. Guinea worm disease has been known since ancient times. It is mentioned in the Egyptian medical Ebers Papyrus, dating from 1550 BC. The name dracunculiasis is derived from the Latin "affliction with little dragons", while the name "guinea worm" appeared after Europeans saw the disease on the Guinea coast of West Africa in the 17th century. A species similar to guinea worms causes disease in other animals. These do not appear to infect humans. It is classified as a neglected tropical disease. It is an endemic disease.
There is no vaccine or medicine to treat or prevent Guinea worm disease. Once a Guinea worm begins emerging, the first step is to do a controlled submersion of the affected area in a bucket of water. This causes the worm to discharge many of its larva, making it less infectious. The water is then discarded on the ground far away from any water source. Submersion results in subjective relief of the burning sensation and makes subsequent extraction of the worm easier. To extract the worm, a person must wrap the live worm around a piece of gauze or a stick. The process can be long, taking anywhere from hours to a week. Gently massaging the area around the blister can help loosen the worm. This is nearly the same treatment that is noted in the famous ancient Egyptian medical text, the Ebers papyrus from 1550 BC. Some people have said that extracting a Guinea worm feels like the afflicted area is on fire. However, if the infection is identified before an ulcer forms, the worm can also be surgically removed by a trained doctor in a medical facility. Guinea worm disease is usually not fatal, the wound where the worm emerges could develop a secondary bacterial infection such as tetanus, which may be life-threatening, a concern in endemic areas where there is typically limited or no access to health care. Analgesics can be used to help reduce swelling and pain and antibiotic ointments can help prevent secondary infections at the wound site. At least in the Northern region of Ghana, the Guinea worm team found that antibiotic ointment on the wound site caused the wound to heal too well and too quickly making it more difficult to extract the worm and more likely that pulling would break the worm. The local team preferred to use something called "Tamale oil" (after the regional capital) which lubricated the worm and aided its extraction. It is of great importance not to break the worm when pulling it out. Broken worms have a tendency to putrefy or petrify. Putrefaction leads to the skin sloughing off around the worm. Petrification is a problem if the worm is in a joint or wrapped around a vein or other important area. Use of metronidazole or thiabendazole may make extraction easier, but also may lead to migration to other parts of the body.