01709nas a2200253   4500000000100000008004100001260001300042653001200055653001200067653000900079653002400088653002500112100001400137700001500151700001500166700000900181700001600190700001100206245006800217300001000285490000700295520113900302022001401441       1980                            d  c1980 Nov10aAnimals10aleprosy10aMice10aMice, Inbred BALB C10aMycobacterium leprae1 aWelch T M1 aGelber R H1 aMurray L P1 aNg H1 aO'Neill S M1 aLevy L00aViability of Mycobacterium leprae after multiplication in mice.  a325-80 v303 a<p>To measure the rate at which Mycobacterium leprae are killed in the course of the mouse footpad infection after the maximum of multiplication has been achieved, M. leprae were harvested shortly before and at intervals after multiplication had reached the level of 10(6) organisms per footpad, serially diluted, and inoculated into the footpads of passage mice. Beginning 1 year later, foot-by-foot harvests of M. leprae were performed from passage mice, and the proportion of viable organisms in the passage inocula was calculated by means of a most-probable-number calculation. In addition, the proportion of solidly staining M. leprae was measured in the passage inocula. The proportion of viable M. leprae in the passage inocula was found to decrease with the time after multiplication to 10(6) organisms per footpad of donor mice; the half-time of loss of viable M. leprae was 25 days. The proportion of solidly staining organisms appeared to be directly related to the proportion of viable organisms, as measured by mouse passage, and inversely proportional to the time after multiplication to 10(6) organisms per footpad.</p>  a0019-9567