02145nas a2200313   4500000000100000008004100001260001300042653001300055653002100068653001200089653002700101653000800128653001100136653000900147653001200156653000900168653000900177653002100186653002500207653000900232100001300241700001800254245005800272856017000330300000900500490000700509520130100516022001401817       1977                            d  c1977 Feb10aAerosols10aAir Microbiology10aAnimals10aDisease Models, Animal10aEar10aFemale10aFoot10aleprosy10aLung10aMice10aMice, Inbred CBA10aMycobacterium leprae10aNose1 aRees R J1 aMcDougall A C00aAirborne infection with Mycobacterium leprae in mice.  uhttp://www.microbiologyresearch.org/docserver/fulltext/jmm/10/1/medmicro-10-1-63.pdf?expires=1504784581&id=id&accname=guest&checksum=9542A41E367FCE694E524659D3F2AC1E  a63-80 v103 a<p>Although the portal of entry and mode of spread of M. leprae in human leprosy are still uncertain, it is widely held that direct person-to-person skin contact is important. This assumption has ignored the fact that patients with highly bacilliferous leprosy have nasal as well as dermal infection and that, since M. leprae is shed predominantly from the nose, leprosy might be an airborne infection. The present study was designed to investigate this possibility with mice exposed to airborne infection with M. leprae. The conditions are described in which thymectomised-irradiated CBA strain mice exposed to M. leprae aerosols sustained an immediate lung retention of 1 X 10(5) bacteria. Fourteen to 24 months later, 33% (10 of 30) of the mice had countable numbers of acid-fast bacilli (greater than 2 X 10(4)) with the characteristics of M. leprae in one or more homogenates prepared from ears, foot pads, nose or lungs. Evidence is presented from the distribution of M. leprae that the infection had arisen from systemic spresd of bacilli initially entering the lungs rather than from multiplication of organisms locally retained there, or in the nose, at the time of airborne infection. The relevance of these results to the possible route of infection of leprosy in man is discussed.</p>  a0022-2615