Rees R J, McDougall A C
J Med Microbiol. 1977 Feb;10(1):63-8. doi: 10.1099/00222615-10-1-63.
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.
尽管麻风分枝杆菌在人类麻风病中的侵入途径和传播方式仍不明确，但人们普遍认为直接的人际皮肤接触很重要。这一假设忽略了以下事实：麻风杆菌大量繁殖的患者存在鼻腔和皮肤感染，而且由于麻风分枝杆菌主要从鼻子排出，麻风病可能是一种空气传播的感染。本研究旨在通过让小鼠暴露于麻风分枝杆菌的空气传播感染来调查这种可能性。描述了这样的条件：胸腺切除并经辐射的CBA品系小鼠暴露于麻风分枝杆菌气溶胶后，肺部立即滞留1×10⁵个细菌。14至24个月后，30只小鼠中有33%（10只）在从耳朵、脚垫、鼻子或肺部制备的一种或多种匀浆中，有数量可计数的具有麻风分枝杆菌特征的抗酸杆菌（大于2×10⁴）。从麻风分枝杆菌的分布情况提供的证据表明，感染是由最初进入肺部的杆菌全身性扩散引起的，而不是由空气传播感染时局部滞留在肺部或鼻子中的微生物繁殖引起的。讨论了这些结果与麻风病在人类中可能的感染途径的相关性。
