Infection by the Guinea worm Dracunculiasis Other names Guinea-worm disease (GWD) Using a matchstick to wind up and remove a guinea worm from the leg of a human Specialty Infectious disease Symptoms Painful blister on lower leg [1] Usual onset Average time of one year after exposure [1] Causes Guinea worms spread by water fleas [1] Diagnostic method Based on symptom [2] Prevention Preventing those infected from putting the wound in drinking water, treating contaminated water [1] Treatment Supportive care [1] Frequency 28 reported cases (2018) [1] Deaths Rare Dracunculiasis , also called Guinea-worm disease ( GWD ), is a parasitic infection by the Guinea worm . [1] A person becomes infected when they drink water that contains water fleas infected with guinea worm larvae . [1] Initially there are no symptoms. [3] About one year later, the female worm forms a painful blister in the skin, usually on a lower limb. [1] Other symptoms at this time may include vomiting and dizziness. [3] The worm then emerges from the skin over the course of a few weeks. [4] During this time, it may be difficult to walk or work. [3] It is very uncommon for the disease to cause death. [1] In humans, the only known cause is Dracunculus medinensis . [3] 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). [1] [3] Outside humans, the young form can survive up to three weeks, [5] during which they must be eaten by water fleas to continue to develop. [1] The larva inside water fleas may survive up to four months. [5] Thus, for the disease to remain in an area, it must occur each year in humans. [6] A diagnosis of the disease can usually be made based on the signs and symptoms. [2] Prevention is by early diagnosis of the disease followed by keeping the infected person from putting the wound in drinking water, thus decreasing the spread of the parasite. [1] Other efforts include improving access to clean water and otherwise filtering water if it is not clean. [1] Filtering through a cloth is often enough to remove the water fleas. [4] Contaminated drinking water may be treated with a chemical called temefos to kill the larva. [1] There is no medication or vaccine against the disease. [1] The worm may be slowly removed over a few weeks by rolling it over a stick. [3] The ulcers formed by the emerging worm may get infected by bacteria. [3] Pain may continue for months after the worm has been removed. [3] In 2019, 53 cases were reported across 4 countries. [7] This is down from an estimated 3.5 million cases in 1986. [3] In 2016 the disease occurred in three countries, all in Africa, down from 20 countries in the 1980s. [1] [8] It will likely be the first parasitic disease to be globally eradicated . [9] Guinea worm disease has been known since ancient times. [3] The method of removing the worm is described in the Egyptian medical Ebers Papyrus , dating from 1550 BC. [10] The name dracunculiasis is derived from the Latin "affliction with little dragons", [11] while the name "guinea worm" appeared after Europeans saw the disease on the Guinea coast of West Africa in the 17th century. [10] Other Dracunculus species are known to infect various mammals, but do not appear to infect humans. [12] [13] Dracunculiasis is classified as a neglected tropical disease . [14] Because dogs may also become infected, [15] the eradication program is monitoring and treating dogs as well. [16] Contents 1 Signs and symptoms 2 Cause 2.1 Hosts 3 Prevention 4 Treatment 5 Epidemiology 5.1 Current situation 5.1.1 Endemic countries 5.2 Eradication program 6 History 6.1 Etymology 7 Other animals 8 References 9 External links Signs and symptoms [ edit ] Dracunculiasis is diagnosed by seeing the worms emerging from the lesions on the legs of infected individuals and by microscopic examinations of the larvae. [17] As the worm moves downwards, usually to the lower leg, through the subcutaneous tissues , it leads to intense pain localized to its path of travel. ... The process may take several weeks. [3] Gently massaging the area around the blister can help loosen the worm. [9] This is nearly the same treatment that is noted in the famous ancient Egyptian medical text, the Ebers papyrus from c. 1550 BC. [10] Some people have said that extracting a Guinea worm feels as if the afflicted area is on fire. [26] [27] 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. [21] Although 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. [28] Analgesics can be used to help reduce swelling and pain and antibiotic ointments can help prevent secondary infections at the wound site. [21] 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. ... For many years the major focus was South Sudan (independent after 2011, formerly the southern region of Sudan ), which reported 76% of all cases in 2013. [31] In 2017 only Chad and Ethiopia had cases. [37] Date South Sudan Mali Ethiopia Chad Total 2011 1,028 [38] 12 [38] 8 [38] 10 [38] 1058 2012 521 [38] 7 [38] 4 [38] 10 [38] 542 2013 113 [38] 11 [38] 7 [38] 14 [38] 148 (including 3 exported to Sudan) 2014 70 [38] 40 [38] 3 [38] 13 [38] 126 2015 5 [38] 5 [38] 3 [38] 9 [38] 22 2016 6 [38] 0 [38] 3 [38] 16 [38] 25 2017 0 [34] 0 [34] 15 [34] 15 [34] 30 2018 10 [39] 0 [39] 0 [39] 17 [39] 28 (including one isolated case in Angola) 2019 4 [39] 0 [39] 0 [39] 47 [39] 53 (including one isolated case in Angola and Cameroon) Eradication program [ edit ] Main article: Eradication of dracunculiasis Logarithmic scale of reported human cases of guinea worm by year, 1989–2017 (2017 data is provisional). [40] Since humans are the principal host for Guinea worm, and there is no evidence that D. medinensis has ever been reintroduced to humans in any formerly endemic country as the result of non-human infections, the disease can be controlled by identifying all cases and modifying human behavior to prevent it from recurring. [9] [41] Over the years, the eradication program has faced several challenges: Inadequate security in some endemic countries Lack of political will from the leaders of some of the countries in which the disease is endemic The need for change in behaviour in the absence of a magic bullet treatment like a vaccine or medication Inadequate funding at certain times [11] The newly recognised transmission of guinea worm through non-human hosts (both domestic and wild animals) History [ edit ] Rod of Asclepius Dracunculiasis has been a recognized disease for thousands of years: Guinea worm has been found in calcified Egyptian mummies . [9] An Old Testament description of "fiery serpents" may have been referring to Guinea worm: "And the Lord sent fiery serpents among the people, and they bit the people; and much people of Israel died." ( Numbers 21:4–9). [10] In the 2nd century BC, the Greek writer Agatharchides described this affliction as being endemic amongst certain nomads in what is now Sudan and along the Red Sea. [42] [10] In the 18th century, Swedish naturalist Carl Linnaeus identified D. medinensis in merchants who traded along the Gulf of Guinea (West African Coast). ... McGraw-Hill. pp. 480 –484. ISBN 978-0-07-128458-5 . ^ Hopkins DR; Ruiz-Tiben E; Downs P; Withers PC Jr.; Maguire JH (2005-10-01).
