Pathogenic free-living amoebae: epidemiology and clinical review

Pathol Biol (Paris). 2012 Dec;60(6):399-405. doi: 10.1016/j.patbio.2012.03.002. Epub 2012 Apr 18.


Free-living amoebae are widely distributed in soil and water. Small number of them was implicated in human disease: Acanthamoeba spp., Naegleria fowleri, Balamuthia mandrillaris and Sappinia diploidea. Some of the infections were opportunistic, occurring mainly in immunocompromised hosts (Acanthamoeba and Balamuthia encephalitis) while others are non opportunistic (Acanthamoeba keratitis, Naegleria meningoencephalitis and some cases of Balamuthia encephalitis). Although, the number of infections caused by these amoebae is low, their diagnosis was still difficult to confirm and so there was a higher mortality, particularly, associated with encephalitis. In this review, we present some information about epidemiology, ecology and the types of diseases caused by these pathogens amoebae.

Publication types

  • Review

MeSH terms

  • Acanthamoeba / classification
  • Acanthamoeba / growth & development
  • Acanthamoeba Keratitis / diagnosis
  • Acanthamoeba Keratitis / epidemiology
  • Amebiasis / epidemiology*
  • Amebiasis / parasitology*
  • Amoeba* / classification
  • Amoeba* / growth & development
  • Amoebozoa / classification
  • Animals
  • Balamuthia mandrillaris / classification
  • Balamuthia mandrillaris / growth & development
  • Central Nervous System Protozoal Infections / epidemiology
  • Central Nervous System Protozoal Infections / parasitology
  • Humans
  • Naegleria
  • Naegleria fowleri / classification
  • Naegleria fowleri / growth & development