Definition of Emerging infectious disease

Emerging infectious disease: An infectious disease that has newly appeared in a population or that has been known for some time but is rapidly increasing in incidence or geographic range.

Examples of emerging infectious diseases include:

  • Ebola virus (first outbreaks in 1976 and the discovery of the virus in 1977),
  • HIV/AIDS (virus first isolated in 1983),
  • Hepatitis C (first identified in 1989, now known to be the most common cause of post-transfusion hepatitis worldwide),
  • Influenza A(H5N1) virus (well known pathogen in birds but first isolated from humans in 1997),
  • Legionella pneumophila (first outbreak in 1976 as Legionnaire disease and since associated with similar outbreaks linked to poorly maintained air conditioning systems),
  • Borrelia burgdorferi (first detected in 1982 and identified as the cause of Lyme disease).

Another example of an emerging infectious disease is the new variant of Creutzfeldt-Jakob disease, which was first described in 1996. The agent is considered to be the same as that causing bovine spongiform encephalitis, a disease which emerged in the 1980s and affected thousands of cattle in the UK and Europe.


Last Editorial Review: 6/14/2012

Search MedTerms:


Back to MedTerms online medical dictionary A-Z List
Pill Identifier Tool

Need help identifying pills and medications?
Use the pill finder tool on RxList.