Eradication of infectious diseases

From Wikipedia, the free encyclopedia

Eradication is the reduction of an infectious disease's prevalence in the global human 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 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. Also, the term eradication is sometimes used in the context of HIV to describe the sought-after total removal of HIV infection from an individual (i.e. a cure).

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[edit] Eradicated

[edit] Smallpox

Smallpox 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.[2]

The virus causing smallpox, Variola vera, has two variants: variola major, with a mortality rate around 30%, and variola minor, with a mortality rate less than 1%. 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.[2]

[edit] Global eradication underway

[edit] Poliomyelitis (polio)

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 eradicated 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.[3]

The following world regions have been declared polio-free:

Poliomyelitis is endemic today only to Nigeria, India, Pakistan, and Afghanistan,[4] with fewer than 2000 cases reported globally each year from 2000-2006.

[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 eggs. 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 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 9,838 cases in 2007 (provisional figures, February 25th 2008), down from an estimated 3.5 million in 1986. The WHO has certified 180 countries free of the disease, and only five countries - Sudan, Ghana, Mali, Nigeria and Niger - are reported to have had endemic guinea worm in 2007.[5] [6]

[edit] Global eradication proposed

[edit] Measles, mumps and rubella

In the 1990s, the governments of the Americas, along with the Pan American Health Organization, launched a plan to eliminate the three MMR vaccine diseases - measles, mumps, and rubella - from the region.[7] Worldwide eradication of these diseases has also been proposed by some smaller organizations.[8]

[edit] Human African Trypanosomiasis

The Pan African Tsetse and Trypanosomiasis Eradication Campaign (PATTEC), launched in July 2000, aims to eradicate the trypanosomes which cause Human African Trypanosomiasis (also known as sleeping sickness) and the cattle disease nagana, primarily by eradicating their vector, the tsetse fly. As of the end of 2007, a full scale eradication effort had not yet been rolled out, but regional elimination campaigns are planned in a number of countries.[9][10]

[edit] Malaria

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.[11][12]

[edit] See also

[edit] References