Tuberculosis (TB) is a contagious disease caused by Mycobacterium tuberculosis (M. tuberculosis). When people infected with tuberculosis cough, sneeze, talk or spit, the bacilli are propelled into the air. Each person with active TB disease will infect on average between 10 and 15 people every year. But people infected with TB bacilli will not necessarily become sick with the disease. The immun...

Quantitative inquiry into changes in the numbers of leprosy bacilli following the inoculation of suspensions of lepromatous tissue into a variety of special bacteriological media did not offer any suggestion of multiplication (1). A similar study of the bacilli in small cubes of nodule tissue incubated in or on bacteriological media, or in tissue culture solutions, also failed to reveal an incr...

When Mycobacterium tuberculosis was grown in Tween-albumin broth without any agitation, the bacilli replicated in the upper, oxygen-rich portion of the medium at a rate that was just balanced by the rate at which the bacilli settled toward the bottom of the tube. When the organisms that accumulated in the sediment were suspended and diluted into fresh medium, they exhibited synchronous replicat...

Postoperative septicaemia with infective endocarditis is a recognized complication of open-heart surgery, in particular homograft or prosthetic replacement of cardiac valves. Several infective organisms, both bacterial and fungal, have been incriminated but infection due to tubercle bacilli has not, to our knowledge, been reported. The clinicopathological features of this condition are discusse...

Forty-three female C57/BL and C3H mice were inoculated with 2.7 X 10(6) Mycobacterium lepraemurium into each hind footpad. The foot thickness and the number of acid-fast bacilli in the footpad and popliteal and inquinal lymph nodes were recorded. In addition the morphological index and the mean bacillary length were determined in the footpad and in the popliteal lymph node. The bacilli multipli...

Experimental infection of the mouse can be used for the determination of virulence of cultures of mammalian tubercle bacilli. The relative virulence of such cultures for the mouse is approximately the same as for the guinea pig. Cultures of virulent and avirulent variants of mammalian tubercle bacilli grown in the depth of Tween 80-albumin liquid medium, on the surface of solid agar modificatio...

Eosin, if present in cultures containing tetanus spores, prevents the germination of these spores when its concentration (in glucose bouillon) reaches 0.2 per cent. When the concentration of the eosin sinks to 0.01 per cent., germination of the spores is no longer inhibited, but the vegetative bacilli developed from the spores execute a highly restrained form of multiplication. When the eosin c...