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Seasonal primary amebic meningoencephalitis (PAM) in the south: summertime is PAM time

James Diaz1

  • 1Louisiana State University Health Sciences Center-New Orleans School of Public Health, USA.

The Journal of the Louisiana State Medical Society : Official Organ of the Louisiana State Medical Society
|August 8, 2012
PubMed

Insights

Primary amebic meningoencephalitis (PAM), a rare but fatal brain infection caused by Naegleria fowleri, is increasingly reported. Risk factors include warm freshwater exposure, with prevention focusing on public health education.

Area of Science:

  • Neurology
  • Infectious Diseases
  • Public Health

Background:

  • Primary amebic meningoencephalitis (PAM) is a rare, fatal central nervous system infection caused by Naegleria fowleri.
  • Recent increases in reported PAM cases globally and in the US necessitate epidemiological analysis.

Purpose of the Study:

  • To analyze a 2007 PAM cluster and review US cases (1937-2007).
  • To statistically analyze demographic, temporal, and behavioral risk factors for PAM.

Main Methods:

  • Epidemiological and statistical analysis of 121 confirmed US PAM cases (1937-2007).
  • Analysis of a 2007 cluster of six PAM cases.
  • Statistical analysis of risk factors.

Main Results:

  • Significant risk factors for PAM in the US include male sex and warm recreational freshwater exposure during July-August.
  • Southern states, including Louisiana, show seasonal patterns.
  • Case fatality rates remain very high despite intensive care and treatments.

Conclusions:

  • PAM prevention relies on public health education and behavioral modification.
  • Further research is needed on wakeboarding as a risk factor and climate change impacts on Naegleria fowleri.

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