抄録
Sixteen isolates from soil sources and three isolates from human sources of Mycobacterium fortuitum in stock cultures were tested for their virulence to mice taking the viable numbers in the lungs and in the spleen as a measure. Among the strains tested, six strains of M. fortuitum isolated from soil sources were shown to be virulent to mice. It was suggested that M. fortuitum occurring in soil may have a chance to infect man and animals.