Air borne transmission of diseases

空气传播疾病是世界卫生组织（WHO）等国际机构更关注的问题之一。这在一定程度上是因为人们非常担心H5N1禽流感在某一阶段会发生变异，成为一种能在人与人之间有效传播的病毒，从而导致全球大流行。目前，该病仅通过长时间密切接触在人与人之间进行零星和无效率的直接传播。最近的大多数病例直接从受感染的禽类传播给人，尽管病死率高达50-60%。从儿童到老年人，所有年龄段的人都被感染过，目前还没有获得许可的人类疫苗，尽管许多疫苗正在开发中。此外，抗流感药物奥司他韦（oseltamivir）的库存有限，有一些文献记载，但对这种病毒的作用相对较小。并非所有国家都能负担得起这种药物，而且它相对昂贵。如果这种H5N1禽流感病毒或其他流感病毒适应于有效的人际传播并引起大流行，那么气溶胶传播很可能成为一个重要的传播途径，特别是在使用呼吸辅助装置（例如氧气面罩和喷雾器）和进行气溶胶产生程序（例如支气管镜检查和插管）的医院。此外，气溶胶传播途径是进行潜在生物恐怖袭击的首选方法，例如2003年在一些美国邮政服务和政府办公室释放的炭疽孢子。该计划的目的是访问并与在该领域工作的领先临床医生和工程师进行互动。气溶胶传播可以简单地视为气溶胶传输和扩散，多相流和湍流方面的专家可以在感染途径方面做出重大贡献。通过从临床角度提高我对这个问题的理解，我们将能够在评估风险方面取得巨大进步，并为减少感染的传播提供投入。

Air borne transmission of diseases is one of the greater concerns for international agencies such as the WHO (World Health Organisation). This derives in part because of the tremendous worry that avian H5N1 influenza will, at some stage, mutate to a form with efficient human-to-human transmission, leading to a worldwide pandemic. At present, the disease is only sporadically and inefficiently transmitted directly between humans by prolonged close contact. Most recent cases are transmitted directly from infected birds to man, albeit with a high case-fatality rate of 50-60%. All ages of individuals have been infected from children to the elderly and at present, there are no licensed vaccines for humans, though many are in development. In addition, there are only limited stockpiles of the anti-influenza drug, oseltamivir, which has some documented, though relatively marginal effects against this virus. Not all countries are able to afford this drug and it is relatively expensive. If this H5N1 avian or other influenza viruses become adapted to efficient human-to-human transmission and cause a pandemic, then aerosol transmission may well become a significant transmission route, particularly in hospitals where respiratory assist devices (e.g. oxygen masks and nebulisers) are used, and aerosol-generating procedures (e.g. bronchoscopy and intubation) are performed. In addition, the aerosol transmission route is the preferred method for conducting potential bioterrorist attacks, e.g. the anthrax spores released in 2003, in some US mail service and government offices.The aim of this proposal is to visit and interact with leading clinicans and engineers working in this areas. Aerosol transmission can be viewed, in a simplistic manner, as aerosol transport and dispersion and one where a specialist in multiphase flow and turbulence can potentially make a substantial contribution in terms of infection routes. By improving my understanding of this problem from a clinical side, we will be able to make dramatic improvements in terms of assessing risk and provide input into reducing the spread of infection.