Mechanisms for aerosolisation of microbial particles from liquid surfaces - understanding fluid mediated transmission pathways of infectious diseases

Transmission through infectious aerosols is a well-recognised route of infection for a number of diseases including TB, measles, SARS and influenza. Despite evidence for airborne transmission, many of the mechanisms that govern the transmission process are poorly understood. This includes the very first stage where the infectious aerosol is formed and released. From a human source, aerosols are released from the respiratory tract through mechanical actions such as talking, breathing or coughing. It is also known that aerosols are released from environmental sources, such as sanitation systems in buildings – especially under the action of splashing.

The process in both human and environmental sources is a complex multiphase problem, which may be influenced by the microorganism itself. Microorganisms can influence the surface tension and rheology of the liquid they are suspended in – we hypothesise this can affect the potential for the microorganism to be released in aerosol as well as the size of the aerosol formed. It may even be that successful microorganisms have evolved such functions. This project aims to look at these aerosol generation processes to understand relationships between mechanical actions, liquid properties, likelihood of aerosol release and potential for the aerosol to contain a microorganism. The project will involve small scale laboratory experiments, room scale aerosol experiments using safe surrogate microorganisms and computational modelling.