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The epidemiology of primary amoebic meningoencephalitis in the USA, 1962–2008

  • J. S. YODER (a1), B. A. EDDY (a1) (a2), G. S. VISVESVARA (a1), L. CAPEWELL (a1) and M. J. BEACH (a1)...

Naegleria fowleri, a free-living, thermophilic amoeba ubiquitous in the environment, causes primary amoebic meningoencephalitis (PAM), a rare but nearly always fatal disease of the central nervous system. While case reports of PAM have been documented worldwide, very few individuals have been diagnosed with PAM despite the vast number of people who have contact with fresh water where N. fowleri may be present. In the USA, 111 PAM case-patients have been prospectively diagnosed, reported, and verified by state health officials since 1962. Consistent with the literature, case reports reveal that N. fowleri infections occur primarily in previously healthy young males exposed to warm recreational waters, especially lakes and ponds, in warm-weather locations during summer months. The annual number of PAM case reports varied, but does not appear to be increasing over time. Because PAM is a rare disease, it is challenging to understand the environmental and host-specific factors associated with infection in order to develop science-based, risk reduction messages for swimmers.

Corresponding author
*Author for correspondence: J. S. Yoder, 4770 Buford Highway, NE Mail Stop F-22, Atlanta, GA 30341, USA. (Email:
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1. GS Visvesvara , H Moura , FL Schuster . Pathogenic and opportunistic free-living amoebae: Acanthamoeba spp., Balamuthia mandrillaris, Naegleria fowleri, and Sappinia diploidea. FEMS Immunology and Medical Microbiology 2007; 50: 126.

3. ND Barnett , Primary amoebic meningoencephalitis with Naegleria fowleri: clinical review. Pediatric Neurology 1996; 15: 230234.

4. JF De Jonckheere . Molecular definition and the ubiquity of species in the genus Naegleria. Protist 2004; 155: 89–103.

7. MR Ettinger , Distribution of free-living amoebae in James River, Virginia, USA. Parasitology Research 2003; 89: 6–15.

9. J Behets , Survey for the presence of specific free-living amoebae in cooling waters from Belgian power plants. Parasitology Research 2007; 100: 12491256.

11. KB Sheehan , PCR detection and analysis of the free-living amoeba Naegleria in hot springs in Yellowstone and Grand Teton National Parks. Applied and Environmental Microbiology 2003; 69: 59145918.

12. B Blair , Naegleria fowleri in well water. Emerging Infectious Diseases 2008; 14: 14991501.

13. RC Maclean , The identification of Naegleria fowleri from water and soil samples by nested PCR. Parasitology Research 2004; 93: 211217.

14. M Fowler , RF Carter . Acute pyogenic meningitis probably due to Acanthamoeba sp.: a preliminary report. British Medical Journal 1965; 2: 740742.

19. JA McCool , Primary amebic meningoencephalitis diagnosed in the emergency department. Annals of Emergency Medicine 1983; 12: 3537.

22. JS Seidel , Successful treatment of primary amebic meningoencephalitis. New England Journal of Medicine 1982; 306: 346348.

25. JG Dos Santos . Fatal primary amebic meningoencephalitis: a retrospective study in Richmond, VA. American Journal of Clinical Pathology 1970; 54: 737742.

30. PE Cogo , Fatal Naegleria fowleri meningoencephalitis, Italy. Emerging Infectious Diseases 2004; 10: 18351837.

33. MM Dorsch , AS Cameron , BS Robinson . The epidemiology and control of primary amoebic meningoencephalitis with particular reference to South Australia. Transactions of the Royal Society of Tropical Medicine and Hygiene 1983; 77: 372377.

34. P-A Cabanes , Assessing the risk of primary amoebic meningoencephalitis from swimming in the presence of environmental Naegleria fowleri. Applied and Environmental Microbiology 2001; 67: 29272931.

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Epidemiology & Infection
  • ISSN: 0950-2688
  • EISSN: 1469-4409
  • URL: /core/journals/epidemiology-and-infection
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