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Appl Environ Microbiol. Jul 1990; 56(7): 2200–2205.
PMCID: PMC184583

Thermal ecology of Naegleria fowleri from a power plant cooling reservoir.


The pathogenic, free-living amoeba Naegleria fowleri is the causative agent of human primary amebic meningoencephalitis. N. fowleri has been isolated from thermally elevated aquatic environments worldwide, but temperature factors associated with occurrence of the amoeba remain undefined. In this study, a newly created cooling reservoir (Clinton Lake, Illinois) was surveyed for Naegleria spp. before and after thermal additions from a nuclear power plant. Water and sediment samples were collected from heated and unheated arms of the reservoir and analyzed for the presence of thermophilic Naegleria spp. and pathogenic N. fowleri. Amoebae were identified by morphology, in vitro cultivation, temperature tolerance, mouse pathogenicity assay, and DNA restriction fragment length analysis. N. fowleri was isolated from the thermally elevated arm but not from the ambient-temperature arm of the reservoir. The probability of isolating thermophilic Naegleria and pathogenic N. fowleri increased significantly with temperature. Repetitive DNA restriction fragment profiles of the N. fowleri Clinton Lake isolates and a known N. fowleri strain of human origin were homogeneous.

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Selected References

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  • Cable BL, John DT. Conditions for maximum enflagellation in Naegleria fowleri. J Protozool. 1986 Nov;33(4):467–472. [PubMed]
  • De Jonckheere JF. Characterization of Naegleria species by restriction endonuclease digestion of whole-cell DNA. Mol Biochem Parasitol. 1987 May;24(1):55–66. [PubMed]
  • De Jonckheere JF. Geographic origin and spread of pathogenic Naegleria fowleri deduced from restriction enzyme patterns of repeated DNA. Biosystems. 1988;21(3-4):269–275. [PubMed]
  • de Jonckheere J, Voorde H. The distribution of Naegleria fowleri in man-made thermal waters. Am J Trop Med Hyg. 1977 Jan;26(1):10–15. [PubMed]
  • Griffin JL. Temperature tolerance of pathogenic and nonpathogenic free-living amoebas. Science. 1972 Nov 24;178(4063):869–870. [PubMed]
  • Griffin JL. The pathogenic amoeboflagellate Naegleria fowleri: environmental isolations, competitors, ecologic interactions, and the flagellate-empty habitat hypothesis. J Protozool. 1983 May;30(2):403–409. [PubMed]
  • Josephson SL, Weik RR, John DT. Concanavalin A-induced agglutination of Naegleria. Am J Trop Med Hyg. 1977 Sep;26(5 Pt 1):856–858. [PubMed]
  • McLaughlin GL, Brandt FH, Visvesvara GS. Restriction fragment length polymorphisms of the DNA of selected Naegleria and Acanthamoeba amebae. J Clin Microbiol. 1988 Sep;26(9):1655–1658. [PMC free article] [PubMed]
  • Stevens AR, Tyndall RL, Coutant CC, Willaert E. Isolation of the etiological agent of primary amoebic meningoencephalitis from artifically heated waters. Appl Environ Microbiol. 1977 Dec;34(6):701–705. [PMC free article] [PubMed]
  • Sykora JL, Keleti G, Martinez AJ. Occurrence and pathogenicity of Naegleria fowleri in artificially heated waters. Appl Environ Microbiol. 1983 Mar;45(3):974–979. [PMC free article] [PubMed]
  • Tyndall RL, Ironside KS, Metler PL, Tan EL, Hazen TC, Fliermans CB. Effect of thermal additions on the density and distribution of thermophilic amoebae and pathogenic Naegleria fowleri in a newly created cooling lake. Appl Environ Microbiol. 1989 Mar;55(3):722–732. [PMC free article] [PubMed]
  • Weik RR, John DT. Agitated mass cultivation of Naegleria fowleri. J Parasitol. 1977 Oct;63(5):868–871. [PubMed]
  • Wellings FM, Amuso PT, Chang SL, Lewis AL. Isolation and identification of pathogenic Naegleria from Florida lakes. Appl Environ Microbiol. 1977 Dec;34(6):661–667. [PMC free article] [PubMed]

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