Eradication of infectious diseases

A child with smallpox. In 1980, the World Health Organization announced the global eradication of smallpox. It is the only human disease to be eradicated worldwide.
Video recording of a set of presentations given in 2010 about humanity's efforts towards malaria eradication

The eradication of infectious diseases is the reduction of the prevalence of an infectious disease in the global host population to zero.[1]

Two infectious diseases have successfully been eradicated: smallpox in humans, and rinderpest in ruminants. There are four ongoing programs, targeting the human diseases poliomyelitis (polio), yaws, dracunculiasis (Guinea worm), and malaria. 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 (elephantiasis) and cysticercosis (pork tapeworm).[2]

The concept of disease eradication is sometimes confused with disease elimination, which is 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.

The targeting of infectious diseases for eradication is based on narrow criteria, as both biological and technical features determine whether a pathogenic organism is (at least potentially) eradicable. The targeted pathogen must not have a significant non-human (or non-human-dependent) reservoir (or, in the case of animal diseases, the infection reservoir must be an easily identifiable species, as in the case of rinderpest). This requires sufficient understanding of the life cycle and transmission of the pathogen. An efficient and practical intervention (such as a vaccine or antibiotic) must be available to interrupt transmission. Studies of measles in the pre-vaccination era led to the concept of the critical community size, the minimal size of the population below which a pathogen ceases to circulate.[3] The use of vaccination programs before the introduction of an eradication campaign can reduce the susceptible population. The disease to be eradicated should be clearly identifiable, and an accurate diagnostic tool should exist. Economic considerations, as well as societal and political support and commitment, are other crucial factors that determine eradication feasibility.[4][5]

  1. ^ Dowdle WR (1998). "The principles of disease elimination and eradication". Bulletin of the World Health Organization. 76 Suppl 2 (S2): 22–5. PMC 2305684. PMID 10063669.
  2. ^ "Diseases considered as candidates for global eradication by the International Task Force for Disease Eradication" (PDF). Cartercenter.org. Retrieved 16 March 2011.
  3. ^ Bartlett MS (1957). "Measles periodicity and community size". J. R. Stat. Soc. Ser. A (120): 48–70.
  4. ^ Dowdle, Walter; Cochi, Stephen L (editors) (2011). Disease Eradication in the 21st Century. Implications for Global Health. The MIT Press, Cambridge, MA
  5. ^ Rinaldi A (March 2009). "Free, at last! The progress of new disease eradication campaigns for Guinea worm disease and polio, and the prospect of tackling other diseases". EMBO Reports. 10 (3): 215–21. doi:10.1038/embor.2009.19. PMC 2658554. PMID 19255577.