COMPARISON OF THE VIRULENCE FOR MICE OF MYCOBACTERIUM-AVIUM AND MYCOBACTERIUM-INTRACELLULARE IDENTIFIED BY DNA PROBE TEST

The virulence of various serovars of Mycobacterium avium and M. intrac ellulare identified by DNA probe test was compared with each other. We found species- and serovar-dependencies of M. avium complex (MAC) vir ulence to mice in terms of mortality, incidence of lung lesions and ba cterial load in the visceral organs, as follows. First, human- or envi ronment-derived M. intracellulare was more virulent for mice, as compa red to M. avium isolated from patients or environmental sources. Secon d, the virulence of MAC isolates belonging to serovars 1, 8, 9 (M. avi um), 14 and 16 (M. intracellulare) is in the order of serovars 16>14>8 >1>9. These aspects were different from those for MAC virulence to hum an and bird, swine and cattle.