Dracunculiasis
Dracunculiasis | |
---|---|
Other names |
|
supportive care | |
Frequency | 14 cases worldwide (2023)[1] |
Deaths | ~1% of cases |
Dracunculiasis, also called Guinea-worm disease, is a
There is no medication to treat or prevent dracunculiasis. Instead, the mainstay of treatment is the careful wrapping of the emerging worm around a small stick or gauze to encourage its exit. Each day, a few more centimeters of the worm emerge, and the stick is turned to maintain gentle tension. Too much tension can break and kill the worm in the wound, causing severe pain and swelling. Dracunculiasis is a disease of extreme poverty, occurring in places with poor access to clean drinking water. Prevention efforts center on filtering drinking water to remove copepods, as well as public education campaigns to discourage people from soaking affected limbs in sources of drinking water, as this allows the worms to spread their larvae.
Accounts consistent with dracunculiasis appear in surviving documents from physicians of Greco-Roman antiquity. 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. The
Cause
Dracunculiasis is caused by infection with the roundworm Dracunculus medinensis.[2] D. medinensis larvae reside within small aquatic crustaceans called copepods. When humans drink the water, they can unintentionally ingest infected copepods. During digestion the copepods die, releasing the D. medinensis larvae. The larvae exit the digestive tract by penetrating the stomach and intestine, taking refuge in the abdomen or retroperitoneal space.[3] Over the next two to three months the larvae develop into adult male and female worms. The male remains small at 4 cm (1.6 in) long and 0.4 mm (0.016 in) wide; the female is comparatively large, often over 100 cm (39 in) long and 1.5 mm (0.059 in) wide.[4] Once the worms reach their adult size they mate, and the male dies.[5] Over the ensuing months, the female migrates to connective tissue or along bones, and continues to develop.[5]
About a year after the initial infection, the female migrates to the skin, forms an ulcer, and emerges. When the wound touches fresh water, the female spews a milky-white substance containing hundreds of thousands of larvae into the water.[5][6] Over the next several days as the female emerges from the wound, she can continue to discharge larvae into surrounding water.[6] The larvae are eaten by copepods, and after two to three weeks of development, they are infectious to humans again.[7]
Signs and symptoms
The first signs of dracunculiasis occur around a year after infection, as the full-grown female worm prepares to leave the infected person's body.
If an affected person submerges the wound in water, the worm spews a white substance releasing its larvae into the water.
Infected people commonly harbor multiple worms – on average 1.8 worms per person,[11] but as many as 40 – which will emerge from separate blisters at the same time.[5] 90% of worms emerge from the legs or feet. However, worms can emerge from anywhere on the body.[5]
Diagnosis
Dracunculiasis is diagnosed by visual examination – the thin white worm emerging from the blister is
Treatment
There is no medicine to kill D. medinensis or prevent it from causing disease once within the body.[13] Instead, treatment focuses on slowly and carefully removing the worm from the wound over days to weeks.[14] Once the blister bursts and the worm begins to emerge, the wound is soaked in a bucket of water, allowing the worm to empty itself of larvae away from a source of drinking water.[14] As the first part of the worm emerges, it is typically wrapped around a piece of gauze or a stick to maintain steady tension on the worm, encouraging its exit.[14] Each day, several centimeters of the worm emerge from the blister, and the stick is wound to maintain tension.[5] This is repeated daily until the full worm emerges, typically within a month.[5] If too much pressure is applied, the worm can break and die, leading to severe swelling and pain at the site of the ulcer.[5]
Treatment for dracunculiasis also includes regular wound care to avoid infection of the open ulcer. The US
Outcomes
Dracunculiasis is a debilitating disease, causing substantial disability in around half of those infected.[9] People with worms emerging can be disabled for the three to ten weeks it takes the worms to fully emerge.[9] When worms emerge near joints, inflammation or infection of the affected area can result in permanent stiffness, pain, or destruction of the joint.[9] Some people with dracunculiasis have continuing pain for 12 to 18 months after the worm has emerged.[5] Around 1% of dracunculiasis cases result in death from secondary infections of the wound.[9]
When dracunculiasis was widespread, it often affected entire villages at once.[10] Outbreaks occurring during planting and harvesting seasons severely impaired a community's agricultural operations – earning dracunculiasis the descriptor "empty granary disease" in some places.[10] Communities affected by dracunculiasis also see reduced school attendance as children of affected parents must take over farm or household duties, and affected children may be physically prevented from walking to school for weeks.[15]
Infection does not create immunity, so people can repeatedly experience dracunculiasis throughout their lives.[16]
Prevention
There is no vaccine for dracunculiasis, and once infected with D. medinensis there is no way to prevent the disease from running its full course.
Epidemiology
Dracunculiasis is now rare, with 14 cases reported worldwide in 2023 and 13 in 2022.[1] This is down from 27 cases in 2020, and dramatically less than the estimated 3.5 million annual cases in 20 countries in 1986 – the year the World Health Assembly called for dracunculiasis' eradication.[20][21] Dracunculiasis remains endemic in four countries: Chad, Ethiopia, Mali, and South Sudan.[22]
Dracunculiasis is a disease of extreme poverty, occurring in places where there is poor access to clean drinking water.[23] Cases tend to be split roughly equally between males and females, and can occur in all age groups.[24] Within a given place, dracunculiasis risk is linked to occupation; people who farm or fetch drinking water are most likely to be infected.[24]
When dracunculiasis was widespread, it had a seasonal cycle, though the timing varied by location. Along the Sahara desert's southern edge, cases peaked during the mid-year rainy season (May–October) when stagnant water sources were more abundant.[24] Along the Gulf of Guinea, cases were more common during the dry season (October–March) when flowing water sources dried up.[24]
History
Diseases consistent with the effects of dracunculiasis are referenced by writers throughout antiquity.
Some have proposed links between dracunculiasis and other prominent ancient texts and symbols. In a 1674 treatise on dracunculiasis,
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.[24] 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.[33][34] In 1976, the WHO estimated the global burden at 10 million cases per year.[34] Ten years later, as the eradication effort was beginning, the WHO estimated 3.5 million cases per year worldwide.[35]
Eradication
The campaign to eradicate dracunculiasis began at the urging of the CDC in 1980.
Each national eradication program had three phases. 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. This continued and evolved as needed until the national burden of disease was very low. Then in a third phase, programs intensified surveillance efforts with the goal of identifying 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.[40]
In May 1991, the 44th World Health Assembly called for an international certification system to verify dracunculiasis eradication country-by-country.
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.[22] 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.[43]
Other animals
In addition to humans, D. medinensis can infect domestic dogs and cats, and wild
Different Dracunculus species can infect snakes, turtles, and other mammals. Animal infections are most widespread in snakes, with nine different species of Dracunculus described in snakes in the United States, Brazil, India, Vietnam, Australia, Papua New Guinea, Benin, Madagascar, and Italy.
Notes
- British Medical Journal's book review pointing out differences in the disease's incubation time and fatality making it a poor match for the Book of Numbers description.[26][25]
- ^ Ghalioungui translates Ebers No. 875 thus:[27]
If you examine a swelling ... on any body-part of man, you must apply thereon a bandage; and if you find it coming and going and clinging to the flesh which is under it ... You must perform a knife treatment, cutting it out with a ds-knife and that which is in its interior is seized with the hnw-instrument ... You must then extirpate it with the ds-knife ... It shall be seized with the hnwjt-part of any colocynch. A swelling that is like a head is to be treated likewise.
- Cyclops copepods due to the similarity between D. medinensis and the fish parasite Cucullanus elegans, the life cycle of which Leuckart had described in 1865.[31]
References
- ^ a b c "Update: 14 human cases of Guinea worm reported in 2023". The Carter Center. 6 March 2024. Retrieved 19 April 2024.
- ^ a b c "Guinea worm disease frequently asked questions". US Centers for Disease Control and Prevention. 16 March 2022. Archived from the original on 28 May 2023. Retrieved 8 August 2022.
- ^ "Guinea worm – biology". US Centers for Disease Control and Prevention. 17 March 2015. Archived from the original on 21 March 2021. Retrieved 17 April 2021.
- ^ a b c Despommier et al. 2019, p. 287.
- ^ a b c d e f g h i j k l m Spector & Gibson 2016, p. 110.
- ^ a b c Hotez 2013, p. 67.
- ^ Despommier et al. 2019, pp. 287–288.
- ^ "Guinea worm – disease". US Centers for Disease Control and Prevention. 4 February 2022. Archived from the original on 22 August 2022. Retrieved 8 August 2022.
- ^ a b c d e f g Despommier et al. 2019, p. 288.
- ^ a b c Hotez 2013, p. 68.
- ^ Greenaway 2004, "Clinical manifestations".
- ^ a b Pearson RD (September 2020). "Dracunculiasis". Merck & Co. Archived from the original on 26 April 2021. Retrieved 25 April 2021.
- ^ a b "Dracunculiasis (Guinea-worm disease)". World Health Organization. Archived from the original on 17 October 2019. Retrieved 9 January 2020.
- ^ a b c d e "Management of Guinea worm disease". US Centers for Disease Control and Prevention. 4 February 2022. Archived from the original on 7 February 2023. Retrieved 8 August 2022.
- ^ Ruiz-Tiben & Hopkins 2006, Section 4.2 "Socio-Economic Impact".
- ^ Callahan et al. 2013, Introduction.
- ^ Despommier et al. 2019, p. 289.
- ^ a b Spector & Gibson 2016, p. 111.
- ^ "Chemical control of copepods". World Health Organization. Retrieved 6 December 2023.
- ^ WHO 2022, Figure 1.
- ^ Despommier et al. 2019, p. 285.
- ^ a b "Year in which countries certified". World Health Organization. Archived from the original on 21 October 2021. Retrieved 20 October 2021.
- ^ Spector & Gibson 2016, p. 109.
- ^ a b c d e Ruiz-Tiben & Hopkins 2006, Section 4. "Epidemiology".
- ^ a b c d e f g h i j Grove 1990, pp. 693–698.
- ^ "Reviews and notices – the diseases of the Bible". The British Medical Journal. 2 (1406): 1283–1284. December 1887.
- ^ Ghalioungui P (1987). The Ebers Papyrus: a new English translation, commentaries, and glossaries. Cairo: Academy of Scienctific Research and Technology. p. 253.
- ^ Miller 1989, p. 251.
- from the original on 25 January 2023. Retrieved 13 June 2022.
- ^ Grove 1990, pp. 698–702.
- ^ a b c Grove 1990, pp. 702–706.
- .
- PMID 20284977.
- ^ a b Biswas et al. 2013, "Decision to Eradicate".
- ^ "Dracunculiasis – global surveillance summary, 1" (PDF). Weekly Epidemiological Record (19). World Health Organization. 10 May 1996. Archived (PDF) from the original on 3 June 2022. Retrieved 2 June 2022.
- ^ Hopkins et al. 2018, Introduction.
- ^ a b c Hotez 2013, p. 69.
- ^ a b c d e Ruiz-Tiben & Hopkins 2006, Section 5. "Eradication Campaign".
- ^ Ruiz-Tiben & Hopkins 2006, Table 1.
- ^ Ruiz-Tiben & Hopkins 2006, Section 5.7 "Strategy for Eradication".
- ^ a b Biswas et al. 2013, Section "Certification of eradication".
- ^ a b "International commission for the certification of dracunculiasis eradication – about us". World Health Organization. Archived from the original on 5 September 2021. Retrieved 5 September 2021.
- ^ Hopkins et al. 2022, "Introduction".
- ^ Hopkins et al. 2022, "Ethiopia".
- ^ Eberhard et al. 2014, "Abstract".
- ^ a b Molyneux & Sankara 2017, Paragraph 7.
- ^ Hopkins et al. 2021, "Table 1".
- ^ Hopkins et al. 2022, "Current status of the campaign".
- ^ Cleveland et al. 2018, "Experimental infections of hosts with D. insignis".
- ^ Cleveland et al. 2018, "Table 1".
- ^ Cleveland et al. 2018, "Dracunculus species of squamates".
- ^ Cleveland et al. 2018, "Dracunculus species in chelonians".
- ^ Cleveland et al. 2018, "Natural infections of D. insignis in wildlife".
- ^ Cleveland et al. 2018, ""Dracunculus species in mammals".
Works cited
- Biswas G, Sankara DP, Agua-Agum J, Maiga A (August 2013). "Dracunculiasis (Guinea worm disease): eradication without a drug or a vaccine". Philos Trans R Soc Lond B Biol Sci. 368 (1623): 20120146. PMID 23798694.
- Callahan K, Bolton B, Hopkins DR, Ruiz-Tiben E, Withers PC, Meagley K (30 May 2013). "Contributions of the Guinea Worm Disease eradication campaign toward achievement of the Millennium Development Goals". PLOS Neglected Tropical Diseases. 7 (5): e2160. PMID 23738022.
- Cleveland CA, Garrett KB, Cozad RA, Williams BM, Murray MH, Yabsley MJ (December 2018). "The wild world of Guinea Worms: A review of the genus Dracunculus in wildlife". Int J Parasitol Parasites Wildl. 7 (3): 289–300. PMID 30094178.
- Despommier DD, Griffin DO, Gwadz RW, Hotez PJ, Knirsch CA (2019). "25. Dracunculus medinensis". Parasitic Diseases (PDF) (7 ed.). Parasites Without Borders. pp. 285–290. Archived (PDF) from the original on 24 November 2021. Retrieved 26 January 2021.
- Eberhard ML, Ruiz-Tiben E, Hopkins DR, Farrell C, Toe F, Weiss A, Withers PC, Jenks MH, Thiele EA, Cotton JA, Hance Z, Holroyd N, Cama VA, Tahir MA, Mounda T (January 2014). "The peculiar epidemiology of dracunculiasis in Chad". Am J Trop Med Hyg. 90 (1): 61–70. PMID 24277785.
- Greenaway C (February 2004). "Dracunculiasis (Guinea worm disease)". CMAJ. 170 (4): 495–500. PMID 14970098.
- Grove DI (1990). A History of Human Helminthology (PDF). C.A.B International. Archived from the original(PDF) on 4 April 2015.
- Hopkins DR, Ruiz-Tiben E, Eberhard ML, Weiss A, Withers PC, Roy SL, Sienko DG (August 2018). "Dracunculiasis eradication: are we there yet?". Am J Trop Med Hyg. 99 (2): 388–395. PMID 29869608.
- Hopkins DR, Weiss AJ, Roy SL, Yerian S, Cama VA (November 2021). "Progress toward global eradication of dracunculiasis, January 2020-June 2021". MMWR Morb Mortal Wkly Rep. 70 (44): 1527–1533. PMID 34735420.
- Hopkins DR, Weiss AJ, Torres-Velez FJ, Sapp SG, Ijaz K (August 2022). "Dracunculiasis eradication: end-stage challenges". Am J Trop Med Hyg. 107 (2): 373–382. PMID 35895421.
- Hotez PJ (2013). "The filarial infections: lymphatic filariasis (elephantiasis) and dracunculiasis (Guinea worm)". Forgotten People, Forgotten Diseases: The Neglected Tropical Diseases and Their Impact on Global Health and Development. American Society for Microbiology (ASM) Press. pp. 57–75.
- Miller RL (1989). "Dqr, spinning and treatment of Guinea worm in P. Ebers 875". The Journal of Egyptian Archaeology. 75: 249–254. JSTOR 3821922.
- Molyneux D, Sankara DP (April 2017). "Guinea worm eradication: Progress and challenges- should we beware of the dog?". PLOS Negl Trop Dis. 11 (4): e0005495. PMID 28426663.
- Ruiz-Tiben E, Hopkins DR (2006). "Dracunculiasis (Guinea worm disease) eradication". Adv Parasitol. Advances in Parasitology. 61: 275–309. PMID 16735167.
- Spector JM, Gibson TE, eds. (2016). "Dracunculiasis". Atlas of Pediatrics in the Tropics and Resource-Limited Settings (2 ed.). ISBN 978-1-58110-960-3.
- Dracunculiasis eradication: global surveillance summary, 2021 (Report). World Health Organization. 27 May 2022. Archived from the original on 29 July 2022. Retrieved 29 July 2022.