In 2017, there were only 20 villages with cases of Guinea worm disease in two countries, both in Africa, compared to 23,735 villages in 21 countries on two continents in 1991.
January 23rd, 2018“…..Without a vaccine or medicine, the ancient parasitic disease is being wiped out mainly through community-based interventions to educate and change behavior, such as teaching people to filter all drinking water and preventing contamination by keeping patients from entering water sources.
In 1986, Guinea worm disease afflicted an estimated 3.5 million people a year in 21 countries in Africa and Asia…..”
Humans become infected by drinking unfiltered water containing copepods (small crustaceans) which are infected with larvae of D. medinensis 
. Following ingestion, the copepods die and release the larvae, which penetrate the host stomach and intestinal wall and enter the abdominal cavity and retroperitoneal space 
. After maturation into adults and copulation, the male worms die and the females (length: 70 to 120 cm) migrate in the subcutaneous tissues towards the skin surface 
. Approximately one year after infection, the female worm induces a blister on the skin, generally on the distal lower extremity, which ruptures. When this lesion comes into contact with water, a contact that the patient seeks to relieve the local discomfort, the female worm emerges and releases larvae 
. The larvae are ingested by a copepod 
and after two weeks (and two molts) have developed into infective larvae 
. Ingestion of the copepods closes the cycle .
Emergence of a Guinea worm from a foot. Photo credit: E. Wolfe, 2003,The Carter Center