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CSU 73/2009: DISEASE ERADICATION

Friday, 20th of November 2009

           CSU 73/2009: DISEASE ERADICATION
 
 This good general introduction is from the Wikipedia. Their list includes
 several diseases not always included in lists of eradicable diseases,
 especially rinderpest and, among human diseases, yaws and onchocerciasis.
 
 New developments in onchocerciasis are discussed at
 http://www.who.int/mediacentre/news/releases/2009/river_blindness_20090701/en/
 
 For weekly polio updates, the best sources is www.polioeradication.org
 
 Full text of the Wikipedia article is at
 http://en.wikipedia.org/wiki/Eradication_of_infectious_diseases
 
 Good reading.
 
 BD
 Eradication of infectious diseases
 From Wikipedia, the free encyclopedia
 
 
 Eradication is the reduction of an infectious disease's prevalence in the
 global human or animal host population to zero.[1] A number of world
 organizations together with local governments are working to fully
 eradicate various diseases. It is sometimes confused with elimination,
 which describes either the reduction of an infectious disease's prevalence
 in a regional population to zero, or the reduction of the global prevalence
 to a negligible amount. Further confusion arises from the use of the term
 eradication to refer to the total removal of a given pathogen from an
 individual patient, particularly in the context of HIV and certain other
 viruses where a cure of this kind is being sought.
 
 
 Seven attempts have been made to date to eradicate infectious diseases in
 humans globally - four aborted programs targeting hookworm, malaria, yaws,
 and yellow fever, one successful program targeting smallpox and two ongoing
 programs targeting poliomyelitis and dracunculiasis. Five more infectious
 diseases have been identified as of April 2008 as potentially eradicable
 with current technology by the Carter Center International Task Force for
 Disease Eradication - measles, mumps, rubella, lymphatic filariasis and
 pork tapeworm.[2] Meanwhile, there has been one major attempt to eradicate
 a disease in animals, namely rinderpest, which is still ongoing.
 
 
 
 Contents
 [hide]
 1 Eradicated
 1.1 Smallpox
 2 Global eradication underway
 2.1 Poliomyelitis (polio)
 2.2 Dracunculiasis
 2.3 Rinderpest
 3 Regional or sub-regional elimination
 established or under way
 3.1 Malaria
 3.2 Lymphatic filariasis
 3.3 Measles and rubella
 3.4 Onchocerciasis
 3.5 Yaws
 4 See also
 5 References
 6 External links
 
 
 
 
 
 [edit] Eradicated
 
 
 [edit] Smallpox
 Main article: Smallpox
 
 
 Smallpox is the only disease to have been eradicated. It became one of the
 first diseases for which there was an effective vaccination when Edward
 Jenner demonstrated in 1798 that inoculation of humans with cowpox could
 protect against smallpox.[3]
 
 
 The virus causing smallpox, Variola vera, has two variants: variola major,
 with a mortality rate around 30 percent, and variola minor, with a
 mortality rate less than 1 percent. The last naturally occurring case of
 variola major was diagnosed in October 1975 in Bangladesh, and the last
 naturally occurring case of variola minor was diagnosed in October 1977 in
 Somalia. The global eradication of smallpox was certified by a commission
 of scientists on December 9, 1979 and endorsed by the World Health Assembly
 on May 8, 1980.[3]
 
 
 [edit] Global eradication underway
 
 
 [edit] Poliomyelitis (polio)
 Main article: Poliomyelitis eradication
 
 
 A dramatic reduction of the incidence of poliomyelitis in industrialized
 countries followed the development of a vaccine in the 1950s. In 1960,
 Czechoslovakia became the first country certified to have eliminated polio.
 
 
 In 1988, the World Health Organization (WHO), Rotary International, the
 United Nations Children's Fund (UNICEF), and the U.S. Centers for Disease
 Control and Prevention (CDC) passed the Global Polio Eradication
 Initiative. Its goal was to eradicate polio by the year 2000. The updated
 strategic plan for 2004–2008 expects to achieve global eradication by
 interrupting poliovirus transmission, using the strategies of routine
 immunization, supplementary immunization campaigns, and surveillance of
 possible outbreaks. The WHO estimates that global savings from eradication,
 due to forgone treatment and disability costs, could exceed one billion
 U.S. dollars.[4]
 
 
 The following world regions have been declared polio-free:
 The Americas (1994)
 Indo-West Pacific region (1997)
 Europe (1998)
 Western Pacific region, including China (2000)
 
 
 The lowest annual polio prevalence seen so far was in 2001, with 483
 reported cases. However, following interruption of vaccination in Nigeria
 in 2003-4 and a reduction in immunisation in India in 2001-2, there was a
 resurgence of polio transmission: in the period of 2002 to 2008, the number
 of global reported cases has remained between 750 and 2000 per year, with
 1,654 cases in 2008. Some of these cases were the result of new
 importations in 27 countries which had previously interrupted transmission,
 leading to many subsequent outbreaks; 13 of these countries are believed to
 have still had active transmission in 2008. Four further countries remain
 in which poliovirus transmission has never been interrupted - Nigeria,
 India, Pakistan, and Afghanistan.[5][6][7]
 
 
 [edit] Dracunculiasis
 
 
 Dracunculiasis, also called Guinea Worm Disease, is a painful and disabling
 parasitic disease caused by a worm, Dracunculus medinensis. It is spread
 through consumption of drinking water infested with copepods hosting
 Dracunculus larvae. The Carter Center has led the effort to eradicate the
 disease, along with the CDC, the WHO, UNICEF, and the Bill and Melinda
 Gates Foundation.
 
 
 Unlike diseases such as smallpox and polio, there is no vaccine nor drug
 therapy for dracunculiasis. Eradication efforts have been based on making
 drinking water supplies safer, isolation of infected individuals and
 through educating people where it is endemic on safe drinking water
 practices. These strategies have proved successful: two decades of
 eradication efforts have reduced its global incidence to 4,619 cases in
 2008 (provisional figures, March 2, 2009), down from an estimated 3.5
 million in 1986, although success has been slower than was hoped - the
 original goal for eradication was 1995. The WHO has certified 180 countries
 free of the disease, and only six countries - Sudan, Ghana, Mali, Nigeria,
 Niger and Ethiopia - are reported to have had domestic transmission of
 guinea worm in 2008.[8][9]
 
 
 [edit] Rinderpest
 
 
 There have been a series of campaigns to eradicate rinderpest, a viral
 disease of cattle belonging to the same family as measles, primarily
 through the use of a live attenuated vaccine. The latest of these campaigns
 was led by the UN Food and Agriculture Organization (FAO). As of 2008, the
 virus had been last seen in 2001; however, on the basis of earlier
 setbacks, the FAO were unwilling to declare it eradicated until the end of
 a period of intensive surveillance due to complete in 2010.[10]
 
 
 [edit] Regional or sub-regional elimination established or under way
 
 
 Some diseases have already been eliminated from parts of the world, and/or
 are currently being targeted for regional elimination. This is sometimes
 described as "eradication", although technically the term only applies when
 this is achieved on a global scale. Even after regional elimination is
 successful, interventions often need to continue to prevent a disease
 becoming re-established. Several of the diseases here listed - Lymphatic
 Filariasis, Measles, Mumps, and Rubella - are among the diseases believed
 to be potentially eradicable by the International Task Force for Disease
 Eradication, and if successful, regional elimination programs may yet prove
 a stepping stone to later global eradication programs.
 
 
 This section does not cover elimination where it is used to mean control
 programs sufficiently tight to reduce the burden of an infectious disease
 or other health problem to a level where they may be deemed to have little
 impact on public health, such as the leprosy, neonatal tetanus, or
 obstetric fistula campaigns.
 
 
 [edit] Malaria
 
 
 Malaria elimination has already been achieved in the USA, Australia and
 Western Europe. As of early 2009, a further 39 countries were in the
 process of eliminating malaria from all or part of their territory.[11] The
 WHO define elimination as having no domestic transmission for the past
 three years. They also define an "elimination stage" when a country is on
 the verge of eliminating malaria, as being <1 case per 1000 people at risk
 per year. According to the 2008 WHO world malaria report, 10 countries were
 in the elimination stage by July 2008 (Algeria, Argentina, Armenia, Egypt,
 El Salvador, Iraq, Paraguay, Republic of Korea, Saudi Arabia and
 Turkmenistan) with a further 11 in the pre-elimination stage (<5 cases per
 1000 people at risk per year).[12] Some countries that are not yet in the
 elimination stage are also moving towards elimination. For instance, the
 elimination of malaria from the last remaining island in the Caribbean to
 have endemic transmission, Hispaniola, is under way. The main tools are
 malaria treatment, mosquito nets, and vector control. Of the two countries
 on the island, malaria is currently endemic throughout Haiti and in 83/143
 municipalities in the Dominican Republic.[13][14] China is also shifting
 focus from control to elimination, with an initial focus on elimination in
 the island province of Hainan.[15]
 
 
 There has also been a discussion of moving to global eradication. At the
 Gates Foundation Malaria Forum in October 2007, Bill and Melinda Gates
 called for a new plan for malaria eradication, by going as far as possible
 with existing tools while also investing in new ones.[16][17] Nearly a year
 later, on September 25, 2008, the Roll Back Malaria (RBM) Partnership
 unveiled the Global Malaria Action Plan, in which a series of measures were
 proposed to eliminate malaria as a global public health concern by 2015,
 eliminate all malaria transmission within 8–10 countries by the same
 deadline, and build towards its eventual global eradication.[18]
 
 
 [edit] Lymphatic filariasis
 
 
 Lymphatic filariasis is an infection of the lymph system by mosquito-borne
 microfilarial worms which can cause elephantiasis. Studies have
 demonstrated that transmission of the infection can be broken when a single
 dose of combined oral medicines is consistently maintained annually for
 approximately seven years.[19] The strategy for eliminating transmission of
 lymphatic filariasis is mass distribution of medicines that kill the
 microfilariae and stop transmission of the parasite by mosquitoes in
 endemic communities.[19] In sub-Saharan Africa, albendazole (donated by
 GlaxoSmithKline) is being used with ivermectin (donated by Merck & Co.) to
 treat the disease, whereas elsewhere in the world albendazole is used with
 diethylcarbamazine.[20] Using a combination of treatments better reduces
 the number of microfilariae in blood.[19] The use of insecticide-treated
 mosquito bed nets also reduces the transmission of lymphatic filariasis as
 well as malaria, which is prevalent in many of the same communities in
 Africa.[19][21] In the Americas, 90% of the burden of lymphatic filariasis
 is on the island of Hispaniola (comprising Haiti and the Dominican
 Republic). An elimination effort to address this is currently under way
 alongside the malaria effort described above; the Dominican Republic
 expects to eliminate its 7 remaining foci by 2010, but lymphatic filariasis
 is still endemic to 110/140 communes in Haiti [14].
 
 
 The efforts of the Global Programme to Eliminate LF are estimated to have
 already prevented 6.6 million new filariasis cases from developing in
 children, and to have stopped the progression of the disease in another 9.5
 million people who have already contracted it. Overall, of 83 endemic
 countries, mass treatment has been rolled out in 48, and elimination of
 transmission reportedly achieved in 21.[22]
 
 
 [edit] Measles and rubella
 
 
 In the 1990s, the governments of the Americas, along with the Pan American
 Health Organization, launched plans to eliminate first measles and then
 also rubella from the region.[23] As of December 2008, the elimination of
 endemic transmission of measles from the Americas has been all but
 achieved, with occasional small outbreaks from imported cases,[24], such as
 a recent outbreak of measles in Canada.[25]. The WHO regional offices for
 Europe and for the Western Pacific are aiming to also achieve regional
 measles elimination by 2010 and 2012 respectively.[26][27] However, the
 global goal remains control (a 90% reduction in measles deaths by 2010 from
 the 757,000 deaths in 2000).[28]
 
 
 Rubella elimination is not yet so advanced, but has also had much success -
 the number of reported rubella cases in the Americas fell from 135,947 in
 1998 to 3,809 in 2008, and domestic rubella transmission in the Americas
 appeared to be confined to northern Argentina as of March 2009 [29]
 
 
 [edit] Onchocerciasis
 
 
 Onchocerciasis (river blindness) is the world's second leading cause of
 infectious blindness. It is caused by the nematode Onchocerca volvulus,
 which is transmitted to people via the bite of a black fly. Elimination of
 this disease is under way in the region of the Americas, where this disease
 is endemic to Brazil, Colombia, Ecuador, Guatemala, Mexico and Venezuela.
 The principal tool being used is mass ivermectin treatment. If successful,
 the only remaining endemic countries would be in Africa and Yemen.[30] In
 most endemic African countries, the focus is currently on control, but a
 few, such as Uganda,[31] are also attempting elimination.
 
 
 [edit] Yaws
 
 
 Yaws is a rarely fatal but highly disfiguring disease caused by the
 spiral-shaped bacterium (spirochete) Treponema pertenue, a relative of the
 syphilis bacteria Treponema pallidum, spread through skin to skin contact
 with infectious lesions. The global prevalence of this disease and the
 other endemic trematoses, Bejel and Pinta, was reduced by the Global
 Control of Treponematoses (TCP) programme between 1952 and 1964 from about
 50 million cases to about 2.5 million (a 95% reduction). However, following
 the cessation of this program these diseases remained at a low prevalence
 in parts of Asia, Africa and the Americas with sporadic outbreaks. Yaws is
 currently targeted by the South-East Asian Regional Office of the WHO for
 elimination from the remaining endemic countries in this region (India,
 Indonesia and East Timor) by 2010, and so far, this appears to have met
 with some success, since no cases have been seen in India since 2004.[32]
 [33]
 
 
 [edit] See also
 Globalization and disease
 Public health
 
 
 [edit] References
 1. ^ Bulletin of the World Health Organization 76 (S2): 14–31. 1998.
 http://whqlibdoc.who.int/bulletin/1998/supplement2/bulletin_1998_76
 (supp2)_13-32.pdf
 2. ^
 http://www.cartercenter.org/resources/pdfs/news/health_publications/itfde/updated_disease_candidate_table.pdf
 
 3. ^ a b "Smallpox". WHO. 2000.
 http://www.who.int/mediacentre/factsheets/smallpox/en/. Retrieved
 2007-11-30.
 4. ^ World Health Organization (2003). Global polio eradication
 initiative : strategic plan 2004-2008. Geneva: WHO. ISBN 924159117X.
 http://www.polioeradication.org/content/publications/2004stratplan.pdf
 . Retrieved 2007-11-30.
 5. ^ "Progress towards interruption of wild poliovirus transmission -
 Worldwide, January 2007 to April 2008". MMWR Morb Mortal Wkly Rep 57
 (18): 489–494. 2008. PMID 18472451.
 http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5718a4.htm. Retrieved
 2009-01-16.
 6. ^ Cochi and Kew (2008). "Polio today: are we on the verge of polio
 eradication?". JAMA 300 (7): 839–41. doi:10.1001/jama.300.7.839. PMID
 18714066. http://jama.ama-assn.org/cgi/content/full/300/7/839.
 Retrieved 2009-01-16.
 7. ^ Global polio eradication initiative website, access date 20
 February 2009 http://www.polioeradication.org/casecount.asp
 8. ^ Dracunculiasis (Guinea Worm) Wrap-up #187: English | Carter Center
 9. ^ Berry, Michele (June 21 2007). "The Tail End of Guinea Worm —
 Global Eradication without a Drug or a Vaccine". The New England
 Journal of Medicine 356 (25): 2561–64. doi:10.1056/NEJMp078089.
 http://content.nejm.org/cgi/content/full/356/25/2561.
 10. ^ Normile (2008). "Driven to Extinction". Science_(journal) 319
 : 1606–1609. doi:10.1126/science.319.5870.1606. PMID 18356500.
 http://www.sciencemag.org/cgi/content/full/319/5870/1606. Retrieved
 2009-03-28.
 11. ^ Malaria Elimination Group description and list of elimination
 countries, access date 05 May 2009
 http://www.malariaeliminationgroup.org/resources/elimination-countries
 
 12. ^ "WHO World Malaria Report 2008". Who.int. 2004-11-08.
 http://www.who.int/malaria/mediacentre/wmr2008/. Retrieved
 2009-02-27.
 13. ^ "WHO Weekly Epidemiology Record 82 (4), 2007". who.int.
 http://www.who.int/wer/2007/wer8204.pdf. Retrieved 2009-03-12.
 14. ^ a b "WHO Weekly Epidemiology Record 84 (11 & 12), 2009".
 who.int. http://www.who.int/wer/2009/wer8411_12.pdf. Retrieved
 2009-03-12.
 15. ^ "UCSF School of Medicine - Global Health Sciences".
 Globalhealthsciences.ucsf.edu.
 http://globalhealthsciences.ucsf.edu/GHG/malaria_elimination.aspx.
 Retrieved 2009-02-27.
 16. ^ Roberts and Enserink (7 December 2007). "MALARIA: Did They
 Really Say ... Eradication?". Science 318: 1544–1545. doi:
 10.1126/science.318.5856.1544.
 http://www.sciencemag.org/cgi/content/full/318/5856/1544.
 17. ^ Announcements - Bill & Melinda Gates Foundation
 18. ^ "Global Malaria Action Plan". Rollbackmalaria.org.
 http://www.rollbackmalaria.org/gmap/index.html. Retrieved
 2009-02-27.
 19. ^ a b c d The Carter Center, "How is Lymphatic Filariasis
 Treated?", http://www.cartercenter.org/health/lf/treatment.html,
 retrieved 2008-07-17
 20. ^ "Lymphatic Filariasis Disease - Carter Center Lymphatic
 Filariasis Program". Cartercenter.org.
 http://www.cartercenter.org/health/lf/index.html. Retrieved
 2009-02-27.
 21. ^ U.S. Centers for Disease Control and Prevention, "Preventing
 Two Diseases with One Net",
 http://www.cdc.gov/malaria/features/nigeria_bednets_program.htm,
 retrieved 2008-07-17
 22. ^ BBC World Service, "'End in sight' for elephantiasis",
 http://news.bbc.co.uk/2/hi/health/7659222.stm, retrieved 2008-10-08
 23. ^ PAHO measles & rubella control main page
 24. ^ CDC MMWR, progress towards measles elimination, 2004
 25. ^ NORTH YORK: Measles outbreak may bring new strategy
 26. ^ WHO resolution EUR/RC55/R7
 27. ^ WHO resolution WPR/RC56.R8
 28. ^ Measles Initiative website, accessed 07 January 2009
 29. ^ PAHO Measles/Rubella Weekly Bulletin volume 15, issue 10.
 30. ^ http://www.who.int/wer/2008/wer8329.pdf
 31. ^ The Carter Center (2008-01-22). "Uganda Attempts Nationwide
 Elimination of River Blindness". Cartercenter.org.
 http://www.cartercenter.org/news/documents/uganda_river_blindness_elimination.html
 . Retrieved 2009-02-27.
 32. ^ Asiedu et al. (2008). "Yaws eradication: past efforts and
 future perspectives". Bulletin of the World Health Organisation 86
 (7): 499–500. doi:10.2471/BLT.08.055608. PMID 18670655.
 http://www.who.int/bulletin/volumes/86/7/08-055608/en/index.html.
 Retrieved 2009-04-02.
 33. ^ WHO South-East Asia report of an intercountry workshop on
 Yaws eradication, 2006
 
 
 [edit] External links
 Carter Center International Task Force for Disease Eradication
 Polio eradication page
 WHO home page
 Retrieved from "
 http://en.wikipedia.org/wiki/Eradication_of_infectious_diseases"