Dracunculus (nematode) edits
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Distribution and eradication
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The species Dracunculus medinensis requires a human host to reproduce. Thus, the elimination of human infection will lead to the extinction of Dracunculus medinensis.
The eradication effort began in 1986 due to around 3.5 million cases being confirmed in African and Asian countries by the Carter Center and other health organizations.[1][2] Since then, the number of cases has been drastically decreasing.
In 2011 only four countries still had the human-infecting Dracunculus medinensis – and of these, Ghana, Ethiopia and Mali have nearly eliminated it. Of the 1785 cases found in 2010, 1690 were in south Sudan, which is 38 per cent fewer than the number of cases in 2009.
In January 2013, the World Health Organization reported finding only 521 cases between January and September 2012.
A major problem in the eradication effort comes from the increased number of dog infections in Chad. As of June 2019, this country has the highest number of cases in the world, 96% of which are from dog infections. However, countries like Mali have reported no human cases for 3.5 years and Ethiopia has no reported human cases for 1.5 years. The effort to eradicate infections has focused mainly stopping the helminth at various points in its life cycle. Preventative measures focus on educating people on the importance of cooking fish thoroughly and preventing other animals from eating discarded portions of the fish. Other measures consist of not allowing reentry into the water from infected individuals. This means keeping infected dogs tied up and away from water and preventing infected people from dipping their appendages in water. Chad even gave monetary incentives for took these steps in confirmed dog or human infections. [3]
Life Cycle
editThe life cycle was elucidated in 1870 when Alexei Pavlovich Fedchenko of Russia discovered the copepod crustacean intermediate host. The life cycle of Dracunculus medinensis has been show to have multiple life stages. Ingestion of infected copepods starts the life cycle in a human host. They then reproduce and grow inside the human for around a year until they burst from a blister on the leg of the host. They then reach water where they can go on to infect more copepods to start the cycle again. They may also be transmitted from ingestion of fish or amphibians that have eaten infected copepods. Other animals may also be infected by Dracunculus medinensis[4]
See also
editReferences
edit- ^ Watts, Susan J. (1987-07-01). "Dracunculiasis in Africa in 1986: Its Geographic Extent, Incidence, and At-Risk Population". The American Journal of Tropical Medicine and Hygiene. 37 (1): 119–125. doi:10.4269/ajtmh.1987.37.119. ISSN 0002-9637.
- ^ "WHO | Dracunculiasis eradication: global surveillance summary, 2017". WHO. Retrieved 2020-02-27.
- ^ Hopkins, Donald R. (2019). "Progress Toward Global Eradication of Dracunculiasis — January 2018–June 2019". MMWR. Morbidity and Mortality Weekly Report. 68. doi:10.15585/mmwr.mm6843a5. ISSN 0149-2195. PMC 6822808. PMID 31671082.
{{cite journal}}: CS1 maint: PMC format (link) - ^ Prevention, CDC-Centers for Disease Control and (2019-04-17). "CDC - Guinea Worm Disease - Biology". www.cdc.gov. Retrieved 2020-02-17.