NHMRC Early Career Fellowship (Australian Public Health) : Understanding and Preventing Airborne Infections (2012–2016)
Abstract:
This project will use a newly developed methodology, broadly applicable to a wide range of pathogens, for assessing the potential for airborne respiratory infection. It will focus on resolving questions faced by clinicians dealing with cystic fibrosis (CF) patients infected with Pseudomonas aeruginosa (Pa). Pa lung infection is a major determinant of morbidity and mortality in CF. The acquisition of Pa begins early in life and increases over time. In most CF centres Pa prevalence in children is 25-30%, increasing to >80% in adults. Previously believed to be acquired sporadically from the environment, genotyping techniques have provided evidence of shared clonal Pa strains within and between CF centres. Recent data strongly suggest that cross-infection of Pa between CF patients via an airborne route can occur in hospital setting. An empirical and mechanistic understanding of how Pa is disseminated into the environment, the associated inter- and intra-patient variation, the survival of Pa post-release, and the efficacy of control measures is lacking. This project will address these gaps in knowledge. Pa has been detected in cough aerosol particles ?3µm in diameter and such droplets can remain airborne for long periods, but their capacity to carry viable Pa over extended durations and distances has not been demonstrated. The unique approach used in this study avoids uncertainties in the interpretation of previous investigations by focussing directly on Pa survival in the aerosol phase over time and distance after coughing. The study will also determine which activities in the clinical environment influence the rate of production of these aerosols, and assess the effectiveness of strategies for minimising the potential for airborne cross infection, including masks and room ventilation. A model with which to examine airborne transmission for other respiratory pathogens beyond Pa will be developed
