Virulence of Naegleria fowleri affected by axenic cultivation and passage in mice.
The virulence of Naegleria fowleri decreases with prolonged axenic cultivation. The decline in virulence of highly virulent, mouse-passaged LEE strain amebae was monitored during 5 years of continuous axenic cultivation. The most rapid decrease in virulence occurred during the first 2 years. Virulence could be restored to original levels by 3 serial passages in mice. The composition of axenic media also affected the virulence of N. fowleri, with a more enriched medium appearing to restore some of the virulence of a weakly virulent strain.
John
D T
DT
Department of Biochemistry and Microbiology, Oklahoma State University, College of Osteopathic Medicine, Tulsa 74107-1898.
Howard
M J
MJ
D000818:Animals; D005856:Germ-Free Life; D008297:Male; D051379:Mice; D016848:Naegleria fowleri / Q000254:growth & development / Q000472:pathogenicity*; D012692:Serial Passage; D014774:Virulence