[Resistance of Mycobacterium fortuitum against varied physical factors and its survival in different surroundings].
OBJECTIVE
To observe the resistance of Mycobacterium fortuitum against some physical factors and its survival in different surroundings.


METHODS
Bacterium solution of Mycobacterium fortuitum was added to the carriers, then it was treated in different interval of time and physical surroundings (high temperature, maximum pressure in ultraviolet ray, dry, sunshine). The treated specimen was cultured to observe the resistance of Mycobacterium fortuitum against physical factors. At the same time, some of bacterium solution were mixed into materials in different surroundings (water, wet soil, and dry soil). The specimen was cultured constantly in different time under the room temperature to observe the growth of Mycobacterium fortuitum in different surroundings.


RESULTS
Mycobacterium fortuitum was killed at 60 degrees C in 135 minutes, 80 degrees C in 60 minutes, 100 degrees C in 5 minutes, and high pressure in 5 minutes (6.8 kg at 121 degrees C, 4.5 kg at 115 degrees C). It can also be killed under hot sunshine in one hour and under the ultraviolet ray at 105.5 microW/cm. Mycobacterium fortuitum can exist in water over 27 months, in wet and dry soil and in dry surroundings for more than one and a half year. With the extending of time, quantities of Mycobacterium fortuitum showed a trend of decline.


CONCLUSIONS
Mycobacterium fortuitum possesses low resistance against high temperature, but higher resistance against ultraviolet ray. The germ shows stronger endurance in different surroundings and can exist for a long time.
Zhuang
B
B
Nanping Sanitary & Anti-Epidemic Station, Nanping, Fujian 353000, China.
Wu
C
C
Lin
G
G
D004777:Environment; D006358:Hot Temperature; D008826:Microbial Sensitivity Tests; D050296:Microbial Viability; D019907:Mycobacterium fortuitum / Q000302:isolation & purification / Q000502:physiology* / Q000528:radiation effects; D013312:Stress, Physiological; D014466:Ultraviolet Rays