Isolation of Naegleria australiensis from an Oklahoma Lake.

Eight isolates of Naegleria australiensis were obtained from a small lake in Tulsa, Oklahoma. The eight strains were isolated during the hot summer months of July through September, when water temperatures ranged from 27 to 33 degrees C. All eight isolates were pathogenic for mice. The mean time to death for mice was 10 days (range 6-13 days). This pathogenic free-living ameba has not before been reported from the United States or the Western Hemisphere.