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Monday, 11th of March 2013 Print

CSU 127/2010: ERADICATION OF INFECTIOUS DISEASES

I last ran this Wikipedia article in 2009. What has changed since then?

·         Giant reductions in polio incidence, especially in India and Nigeria

·         FAO declaration of rinderpest eradication

·         Measles elimination targets set in five of WHO’s six regions

·         Rubella elimination targets set in two of WHO’s six regions

·         Shrinking of the onchocerciasis and dracunculiasis maps

Can the world go after more than one eradication target at one time? Whatever you may have heard to the contrary, the evidence says ‘yes.’

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 host population to zero.[1] 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 (also known as clearance of an infection), particularly in the context of HIV and certain other viruses where such cures are sought.

Eight attempts have been made to date to eradicate infectious diseases - four aborted programs targeting hookworm, malaria, yaws, and yellow fever, two successful programs targeting smallpox and rinderpest, 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]

Contents

1 ERADICATED

1.1 Smallpox

1.2 Rinderpest

 

2 GLOBAL ERADICATION UNDERWAY

2.1 Poliomyelitis (polio)

2.2 Dracunculiasis

 

3 REGIONAL ELIMINATION ESTABLISHED OR UNDER WAY

3.1 Malaria

3.2 Lymphatic filariasis

3.3 Measles

3.4 Rubella

3.5 Onchocerciasis

3.6 Yaws

3.7 Bovine spongiform encephalopathy (BSE) and new variant Creutzfeldt–Jakob disease (vCJD)

4 In fiction

5 See also

6 References

7 External links

Eradicated

So far, two diseases have been successfully eradicated - one specifically affecting humans (smallpox), and one affecting a wide range of ruminants (rinderpest).

Smallpox

Main article: Smallpox

Smallpox was the first disease to be eradicated by human undertakings, and the only human infectious disease to have been eradicated so far. It became the first disease 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]

Rinderpest

Main article: Rinderpest

During the 20th century, there were a series of campaigns to eradicate rinderpest, a viral disease which infected cattle and other ruminants and belonged to the same family as measles, primarily through the use of a live attenuated vaccine.[4] The final, successful campaign was led by the Food and Agriculture Organization (FAO) of the United Nations. On 14 October 2010, with no diagnoses for nine years, the FAO announced that the disease had been completely eradicated.[5]

Global eradication underway

Poliomyelitis (polio)

Main article: Poliomyelitis eradication

International Polio Cases by Year

Year

Estimated

Recorded

1975

-

49,293

1980

400,000

52,552

1985

-

38,637

1988

350,000

35,251

1990

-

23,484

1993

100,000

10,487

1995

-

7,035

2000

-

2,971[6]

2001

-

483

2002

-

1,922

2003

-

784

2004

-

1,258

2005

-

1,998

2006

-

1,985

2007

-

1,315

2008

-

1,652

2009

-

1,606

References:[7][8][9][10][11]

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.[12]

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 2009, the number of global reported cases has remained between 750 and 2000 per year, with 1,606 cases in 2009. Some of these cases were the result of new importations in 31 countries which had previously interrupted transmission, leading to many subsequent outbreaks; 19 of these countries reported cases in 2009. Four further countries remain in which poliovirus transmission has never been interrupted (Nigeria, India, Pakistan, and Afghanistan).[13][14][15]

Dracunculiasis

International Guinea Worm Cases by Year [16]

Year

Reported Cases

Countries

1989

892,055

16

1995

129,852

19

2000

75,223

16

2001

63,717

16

2002

54,638

14

2003

32,193

13

2004

16,026

13

2005

10,674

12

2006

25,217 [17]

10

2007

9,585

9

2008

4,619

7

2009

3,190

5

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 guinea worm. Eradication efforts have been based on making drinking water supplies safer (e.g. by provision of borehole wells, or through treating the water with larvicide), on containment of infection and on education for safe drinking water practices. These strategies have produced many successes: two decades of eradication efforts have reduced guinea worm's global incidence to 3,190 cases in 2009, down from an estimated 3.5 million in 1986. 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 four countries - Sudan, Ghana, Mali, and Ethiopia - reported domestic transmission of guinea worm in 2009 (one further country, Niger, reported imported cases). 86% of all cases reported in 2009 were in Sudan, and 83% of cases were contained.[18][19] As of 2010, the WHO predict it will be "a few years yet" before eradication is achieved, on the basis that it took 6-12 years for the countries that have so far eliminated guinea worm transmission to do so after reporting a similar number of cases to that reported by Sudan in 2009.[20]

Regional elimination established or under way

Some diseases have already been eliminated from large regions 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.[21] Even after regional elimination is successful, interventions often need to continue to prevent a disease becoming re-established. Three of the diseases here listed (Lymphatic Filariasis, Measles, 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.

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.[22] 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).[23] 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 of 143 municipalities in the Dominican Republic.[24][25] China is also shifting focus from control to elimination, with an initial focus on elimination in the island province of Hainan.[26]

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.[27][28] Nearly a year later, on September 25, 2008, the Roll Back Malaria (RBM) Partnership unveiled the Global Malaria Action Plan (GMAP), 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.[29]

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.[30] 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.[30] 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.[31] Using a combination of treatments better reduces the number of microfilariae in blood.[30] Avoiding mosquito bites, such as by using insecticide-treated mosquito bed nets, also reduces the transmission of lymphatic filariasis.[30][32] 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 seven remaining foci by 2010, but lymphatic filariasis is still endemic to 110 of 140 communes in Haiti.[25]

As of October 2008, 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.[33]

Measles

Five out of six WHO regions have goals to eliminate measles, and at the 63rd World Health Assembly in May 2010, delegates agreed to move towards eventual eradication, although no specific global target date has yet been agreed[34][35][36]The Americas set a goal in 1994 to eliminate measles and rubella transmission by 2000, and successfully achieved regional measles elimination in 2002, although there have been occasional small outbreaks from imported cases since then.[37] Europe had set a goal to eliminate measles transmission by 2010, but were hindered by the MMR vaccine controversy and by low uptake in certain groups, and despite achieving low levels by 2008, European countries have since experienced a small resurgence in cases. The Eastern Mediterranean also had goals to eliminate measles by 2010, The Western Pacific aims to eliminate the disease by 2012, and in 2009 the regional committee for Africa agreed a goal of measles elimination by 2020. As of May 2010, only the South-East Asian region has yet to set a target date for elimination of measles transmission.[34]

In 2005, a global target was agreed for a 90% reduction in measles deaths by 2010 from the 757,000 deaths in 2000; estimates for 2008 show a 78% decline so far to 164,000 deaths.[38] However, some have been pushing to attempt global eradication.[39] This was updated at the 2010 world health assembly to a targeted 95% reduction in mortality by 2015, alongside specific vaccination and structural targets.[34][35] A study of the costs of eradicating measles compared to the costs of maintaining indefinite control was commissioned in 2009 by the WHO and the Bill and Melinda Gates Foundation.[40]

Rubella

Two WHO regions have set 2010 as a target for rubella elimination. The WHO region of the Americas set itself a target for regional elimination of rubella and congenital rubella syndrome by 2010. As of 2010, the last confirmed endemic case of rubella in the Americas was in Argentina in February 2009[41] and verification of regional elimination is currently under way and due to complete by 2012.[42] The WHO European region also set a target of 2010.[43] However, as of 2008 there were still 20,579 reported cases of rubella, 311 of which were laboratory confirmed, just among the 27 countries reporting data to EUVAC.[44]

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.[45] In Africa, it is estimated that >102 million people in 19 countries are at high risk of onchocerciasis infection, and in 2008, 56.7 million people in 15 of these countries received community-directed treatment with ivermectin. Since adopting such treatment measures in 1997, the African Programme for Onchocerciasis Control reports a reduction in the prevalence of onchocerciasis in the countries under its mandate from a pre-intervention level of 46.5% in 1995 to 28.5% in 2008.[46] Some African countries, such as Uganda,[47] are also attempting elimination and successful elimination was reported in 2009 from two endemic foci in Mali and Senegal. [48]

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.[49][50]

[edit] Bovine spongiform encephalopathy (BSE) and new variant Creutzfeldt–Jakob disease (vCJD)

Following an epidemic of vCJD in the UK in the 1990s, there have been campaigns to eliminate BSE in cattle across the EU and beyond which appear to have achieved large reductions in the number of cattle with this disease.[51] Cases of vCJD have also fallen since then, for instance from an annual peak in the UK of 28 cases in 2000 to 2 cases in 2009.[52]

Following the ongoing eradication effort, only 70 cases of BSE were reported worldwide in 2009, the fewest since at least 1988.[53][54]

In fiction

Futures and futuristic alien civilisations in which some or all infectious diseases have been eradicated are a staple of science fiction. Examples include:

The War of the Worlds by H. G. Wells, in which the Martian race have long eradicated their own infectious diseases, leaving them vulnerable to Earth pathogens following the atrophy of their natural defences.

The Evitable Conflict, by Isaac Asimov, describes a future run by Machines in the manner which they see as most conducive to man's best interests, in which "we have eradicated the anopheles mosquito and the tsetse fly".

See also

Vaccination

Globalization and disease

Drugs for neglected diseases initiative

References

^ Dowdle, Walter R (1998). "The Principles of Disease Elimination and Eradication". Bulletin of the World Health Organization 76 (S2): 22–25.  http://whqlibdoc.who.int/bulletin/1998/supplement2/bulletin_1998_76(supp2)_13-32.pdf

^ http://www.cartercenter.org/resources/pdfs/news/health_publications/itfde/updated_disease_candidate_table.pdf

^ a b "Smallpox". WHO. 2000. http://www.who.int/mediacentre/factsheets/smallpox/en/. Retrieved 2007-11-30. 

^ Dennis Normile (2008). "Driven to Extinction". Science 319 (5870): 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. 

^ "UN 'confident' disease has been wiped out". BBC. 14 October 2010. http://www.bbc.co.uk/news/science-environment-11542653. Retrieved 14 October 2010. 

^ Due to the large increase in the number of vaccinators and field workers since 1998, the number of estimated cases is thought to be reasonably close to the actual reported number of cases in recent years. Aylward, Bruce, Jennifer Linkins. "Polio Eradication:mobilizing and managing the human resources". World Health Organization. http://www.who.int/bulletin/volumes/83/4/268.pdf#search=%222005%20%22%20estimated%20polio%20cases%22%22. Retrieved 2007-02-01. 

^ Mastny, Lisa (January 25, 1999). "Eradicating Polio: A Model for International Cooperation". Worldwatch Institute. http://www.worldwatch.org/node/1644. Retrieved 2007-02-02. 

^ "PolioPlus Milestones". Rotary International. http://www.rotary.org/foundation/polioplus/news/milestones/index.html. Retrieved 2007-02-22. 

^ "Wild Poliovirus Weekly Update". Global Polio Eradication Initiative. http://www.polioeradication.org/casecount.asp. Retrieved 2010-02-15. 

^ "WHO Vaccine Preventable Diseases: Monitoring system" (PDF). World Health Organization. 2006. http://www.who.int/vaccines-documents/GlobalSummary/GlobalSummary.pdf. Retrieved 2007-02-02. 

^ Lee, Jong Wook (1995). "Ending polio - now or never?". The Progress of Nations. Unicef. http://www.unicef.org/pon95/heal0002.html. Retrieved 2007-02-02. 

^ 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. 

^ "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. 

^ Cochi and Kew; Kew, O (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. 

^ Global polio eradication initiative website, access date 05 March 2010 http://www.polioeradication.org/casecount.asp

^ WHO. "Dracunculiasis Epidemiological Data (1989-2008)". World Health Organization. http://www.who.int/dracunculiasis/epidemiology/Epidemiological_data.pdf. Retrieved 2009-09-14. 

^ Increase in reported cases resulted from improved reporting in southern Sudan following the peace agreement in 2005 http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5632a1.htm

^ Dracunculiasis (Guinea Worm) Wrap-up #196: English | Carter Center

^ 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. PMID 17582064. http://content.nejm.org/cgi/content/full/356/25/2561

^ World Health Organisation. Weekly Epidemiology Record 85, no 19, p. 166: Dracunculiasis eradication - global surveillance summary, 2009. World Health Organization. http://www.who.int/entity/wer/2010/wer8519.pdf. Retrieved 2010-05-14 

^ International task force for disease eradication program definitions, http://www.cartercenter.org/health/itfde/program_definition.html, retrieved 2010-07-11 

^ Malaria Elimination Group description and list of elimination countries, access date 05 May 2009 http://www.malariaeliminationgroup.org/resources/elimination-countries

^ "WHO World Malaria Report 2008". Who.int. 2004-11-08. http://www.who.int/malaria/publications/atoz/9789241563697/en/index.html. Retrieved 2010-10-11. 

^ "WHO Weekly Epidemiology Record 82 (4), 2007". who.int. http://www.who.int/wer/2007/wer8204.pdf. Retrieved 2009-03-12. 

^ 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. 

^ "UCSF School of Medicine - Global Health Sciences". Globalhealthsciences.ucsf.edu. http://globalhealthsciences.ucsf.edu/GHG/malaria_elimination.aspx. Retrieved 2009-02-27. 

^ Roberts and Enserink; Enserink, M. (7 December 2007). "MALARIA: Did They Really Say ... Eradication?". Science 318 (5856): 1544–1545. doi:10.1126/science.318.5856.1544. PMID 18063766. http://www.sciencemag.org/cgi/content/full/318/5856/1544

^ Announcements - Bill & Melinda Gates Foundation

^ "Global Malaria Action Plan". Rollbackmalaria.org. http://www.rollbackmalaria.org/gmap/index.html. Retrieved 2009-02-27. 

^ a b c d The Carter Center. ""How is Lymphatic Filariasis Treated?"". Archived from the original on 2008-04-14. http://web.archive.org/web/20080414064850/http://www.cartercenter.org/health/lf/treatment.html. Retrieved 2008-07-17. 

^ "Lymphatic Filariasis Disease - Carter Center Lymphatic Filariasis Program". Cartercenter.org. http://www.cartercenter.org/health/lf/index.html. Retrieved 2009-02-27. 

^ U.S. Centers for Disease Control and Prevention, "Lymphatic filariasis prevention", http://www.cdc.gov/ncidod/dpd/parasites/lymphaticfilariasis/prevention_lymphatic_filar.htm, retrieved 2010-07-08 

^ BBC World Service (2008-10-08). ""'End in sight' for elephantiasis"". http://news.bbc.co.uk/2/hi/health/7659222.stm. Retrieved 2008-10-08. 

^ a b c "Sixty-third World Health Assembly Agenda provisional agenda item 11.15 Global eradication of measles.". http://apps.who.int/gb/ebwha/pdf_files/WHA63/A63_18-en.pdf. Retrieved 02 June 2010. 

^ a b "Sixty-third World Health Assembly notes from day four". http://www.who.int/mediacentre/events/2010/wha63/journal4/en/index.html. Retrieved 02 June 2010. 

^ "State of the world's vaccines and immunization. Third edition". World Health Organization. 2009-11-24. http://www.who.int/immunization/sowvi/en/index.html. Retrieved 2 February 2010. 

^ CDC MMWR, progress towards measles elimination, 2004

^ WHO Weekly Epidemiology Record 84 (49), 4th December 2009 http://www.who.int/wer/2009/wer8449/en/index.html

^ de Quadros, 2004. "Can measles be eradicated globally?" Bulletin of the World Health Organization 82(2) http://www.scielosp.org/scielo.php?script=sci_arttext&pid=S0042-96862004000200011&lng=en&nrm=iso&tlng=en, accessed 15 November 2009

^ WHO Weekly Epidemiology Record 84(44), Meeting of the International Task Force for Disease Eradication, June 2009, pages 459-465 http://www.who.int/wer/2009/wer8444.pdf

^ "January-February 2010 Rubella Watch", http://new.paho.org/hq/index.php?option=com_content&task=view&id=782&Itemid=2180&lang=en, retrieved 2010-07-11 

^ "March-April 2010 Rubella Watch", http://new.paho.org/hq/index.php?option=com_content&task=view&id=782&Itemid=2180&lang=en, retrieved 2010-07-11 

^ , http://www.euro.who.int/__data/assets/pdf_file/0008/79028/E87772.pdf, retrieved 2010-07-11 

^ "EUVAC.net rubella surveillance report 2008, http://www.euvac.net/graphics/euvac/pdf/rubella_report_2008.pdf, retrieved 2010-07-11 

^ WHO Weekly Epidemiology Record, 2008, http://www.who.int/wer/2008/wer8329.pdf 

^ WHO Weekly Epidemiology Record, 2010, http://www.who.int/wer/2010/wer8504/en/index.html 

^ 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. 

^ http://www.plosntds.org/article/info%3Adoi%2F10.1371%2Fjournal.pntd.0000497

^ Asiedu et al.; Amouzou, B; Dhariwal, A; Karam, M; Lobo, D; Patnaik, S; Meheus, A (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. PMC 2647478. http://www.who.int/bulletin/volumes/86/7/08-055608/en/index.html. Retrieved 2009-04-02. 

^ WHO South-East Asia report of an intercountry workshop on Yaws eradication, 2006

^ http://ec.europa.eu/food/fs/bse/bse20_en.html

^ UK CJD case count http://www.cjd.ed.ac.uk/figures.htm

^ http://www.oie.int/eng/info/en_esbmonde.htm

^ http://www.oie.int/eng/info/en_esbru.htm

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