A person becomes infected by drinking water contaminated with Guinea-worm larvae that reside inside copepods (a type of small crustacean).

Around a year later, the adult female migrates to an exit site – usually the lower leg – and induces an intensely painful blister on the skin.

Instead, the mainstay of treatment is the careful wrapping of the emerging worm around a small stick or gauze to encourage and speed up its exit.

Dracunculiasis is a disease of extreme poverty, occurring in places with poor access to clean drinking water.

In the 19th and early 20th centuries, dracunculiasis was widespread across much of Africa and South Asia, affecting as many as 48 million people per year.

[2] As the worm migrates to its exit site – typically the lower leg – some people have allergic reactions, including hives, fever, dizziness, nausea, vomiting, and diarrhea.

[5] Over 1–3 days, the blister grows larger, begins to cause severe burning pain, and eventually bursts, leaving a small open wound.

[5] As the worm emerges, the open blister often becomes infected with bacteria, resulting in redness and swelling; the formation of abscesses; or, in severe cases, gangrene, sepsis, or tetanus.

[11] Outbreaks occurring during planting and harvesting seasons severely impaired a community's agricultural operations – earning dracunculiasis the descriptor "empty granary disease" in some places.

[19] Public education campaigns inform people in affected areas how dracunculiasis spreads and encourage those with the disease to avoid soaking their wounds in bodies of water that are used for drinking.

Along the Sahara desert's southern edge, cases peaked during the mid-year rainy season (May–October) when stagnant water sources were more abundant.

Plutarch's Symposiacon refers to a (lost) description by the 2nd-century BCE writer Agatharchides concerning a "hitherto unheard-of disease" in which "small worms issue from [people's] arms and legs ... insinuating themselves between the muscles [to] give rise to horrible sufferings".

In a 1674 treatise on dracunculiasis, Georg Hieronymous Velschius ascribed serpentine figures in several ancient icons to Dracunculus, including Greek sculptures, signs of the zodiac, Arabic lettering, and the Rod of Asclepius, a common symbol of the medical profession.

[26] Similarly, parasitologist Friedrich Küchenmeister proposed in 1855 that the "fiery serpents" that plague the Hebrews in the Old Testament represented dracunculiasis.

[26][note 1] In 1959, parasitologist Reinhard Hoeppli proposed that a prescription in the Ebers papyrus – a medical text written around 1500 BCE – referred to the removal of a Guinea worm, an identification endorsed ten years later by the physician and Egyptologist Paul Ghalioungui; this would make the Ebers papyrus the oldest known description of the disease.

[note 2][29] Carl Linnaeus included the Guinea worm in his 1758 edition of Systema Naturae, naming it Gordius medinensis.

[31] Alexei Pavlovich Fedchenko filled a major gap with his 1870 publication describing that D. medinensis larvae can infect and develop inside copepods.

[32] In the 19th and 20th centuries, dracunculiasis was widespread across nearly all of Africa and South Asia, though no exact case counts exist from the pre-eradication era.

[25] In a 1947 article in the Journal of Parasitology, Norman R. Stoll used rough estimates of populations in endemic areas to suggest that there could have been as many as 48 million cases of dracunculiasis per year.

[39] By 1996, national eradication programs had been launched in every country with endemic dracunculiasis: Ghana and Nigeria in 1989; Cameroon in 1991; Togo, Burkina Faso, Senegal, and Uganda in 1992; Benin, Mauritania, Niger, Mali, and Côte d'Ivoire in 1993; Sudan, Kenya, Chad, and Ethiopia in 1994; Yemen and the Central African Republic in 1995.

The first phase consisted of a nationwide search to identify the extent of dracunculiasis transmission and develop national and regional plans of action.

The second phase involved the training and distribution of staff and volunteers to provide public education village-by-village, surveil for cases, and deliver water filters.

Then, in a third phase, programs intensified surveillance efforts to identify each case within 24 hours of the worm emerging and preventing the person from contaminating drinking water supplies.

Most national programs offered voluntary in-patient centers, where those affected could stay and receive food and care until their worms were removed.

[42] Since the initiation of the global eradication program, the ICCDE has certified 15 of the original endemic countries as having eradicated dracunculiasis: Pakistan in 1997; India in 2000; Senegal and Yemen in 2004; the Central African Republic and Cameroon in 2007; Benin, Mauritania, and Uganda in 2009; Burkina Faso and Togo in 2011; Côte d'Ivoire, Niger, and Nigeria in 2013; and Ghana in 2015.

[23] In 2020, the 76th World Health Assembly endorsed a new guidance plan, the Roadmap for Neglected Tropical Diseases 2021–2030, which sets a 2027 target for eradication of dracunculiasis, allowing certification by the end of 2030.

[48][49] Domestic ferrets can be infected with D. medinensis in laboratory settings, and have been used as an animal disease model for human dracunculiasis.