The heat tolerance of 27 Enterococcus faecium isolates in water was st
udied. Stationary phase cultures including vancomycin resistant and se
nsitive clinical and food isolates were exposed to heat at 60 degrees,
65 degrees, 71 degrees, and 80 degrees C for one, three, 10, and 30 m
inutes and the log(10) reductions in bacterial counts were determined.
Exposure at 71 degrees and 80 degrees C resulted in >6 log(10) reduct
ion in viable counts for all isolates. Seven (24%) isolates survived (
<5 log(10) reduction) heat at 65 degrees C for 10 minutes. The E faeci
um isolates were more resistant to heat than the two E faecalis refere
nce strains. No differences in heat tolerance were observed between va
ncomycin sensitive and resistant strains or between isolates of human
or food origin.