# **Introduction**

In 1986, there were over 2.25 million cases of dracunculiasis (Guinea worm disease) worldwide.<sup>2</sup> Ten years later, in 1996, the estimated worldwide incidence of dracunculiasis was close to 330,000 cases.<sup>3</sup> This remarkable decline in the incidence of dracunculiasis has been the result of the Global Dracunculiasis Eradication Campaign (GDEC). GDEC is spearheaded by national eradication programs and is supported by a coalition of agencies, institutions, organizations, and bilateral donors. As the numbers attest, as a result of GDEC, dracunculiasis has been virtually eliminated as a major public health problem and an impediment to socioeconomic development in several African countries as well as in India, Pakistan, and Yemen.<sup>4</sup> Dracunculiasis was eradicated from Pakistan in 1994.5 In 1996, an overwhelming majority (78%) of a provisional total of 152,185 reported cases of dracunculiasis occurred in Sudan, where civil strife has complicated the successful operation of its national Guinea worm eradication program.

Dracunculiasis is caused by the nematode parasite _Dracunculus medinensis._ An individual becomes infected by drinking water containing tiny crustaceans (copepods) which harbor infective larvae and act as an intermediate host. After about one year, the mature female worm approaches the skin, eventually causing a blister to form. The blister ruptures (within 24-48 hours) causing the head of the worm to become exposed to the external environment. When the affected person enters a body of water the worm releases myriads of larvae which are then ingested by copepods (water fleas). Upon release of the larvae, the worm dies and must be extracted manually, usually by rolling a few centimeters of the worm each day on a stick. The extraction of the worm is a slow and intensely painful process incapacitating individuals for weeks, and often longer. In addition to the blisters and skin lesions, secondary bacterial infections exacerbate local inflammation, and often lead to sepsis, abscesses, arthritis, contracture of joints, or even tetanus. In a small number of instances, infection may be associated with permanent crippling similar to polio. There is no cure for the disease, but it is amenable to prevention through educating people about the origin of the disease and what they can do to prevent it: filtering their drinking water through a piece of cloth to remove copepods, and never entering a source of drinking water (or allowing someone else to do it) when a Guinea worm is emerging. The disease can also be prevented by providing safe sources of

- 2 Watts (1987) estimated the worldwide incidence of dracunculiasis tobe 3.3. million cases. Review of the available data, while preparing this paper, warranted that we revise that 1986 benchmark to 2.25 million cases.

- **3** This differs from the provisional number of cases reported to the World Health Organization (WHO) of 152,185. This discrepancy is largely caused by incomplete knowledge of the full extent of dracunculiasis and incomplete reporting of cases in Sudan.

- **4** The entire list of countries covered is: Benin, Burkina Faso, Cameroon, Chad, Cote d'Ivoire, Ethiopia, Ghana, India, Kenya, Mali, Mauritania, Niger, Nigeria, Pakistan, Senegal, Sudan, Togo, Uganda, and Yemen.

See Hopkins _et al. (I 995)._ 2