Making Australia resilient to airborne infection transmission
Project Aims
The COVID-19 pandemic is still evolving with daily new cases increasing globally as many regions experience a second wave. Still more questions than answers remain to the many aspects of the pandemic. One important question that has emerged is: How can we minimise the risk of airborne infection transmission for any respiratory viruses in a countless number of congregate settings, e.g. offices, schools, factories, residential aged care, cruise ships, etc., where most of the population spends a substantial fraction of the day (Australian Government, 2020a), working, studying, travelling, enjoying entertainment, resting and/or undergoing medical care as part of their daily lives?
This question goes far beyond the current COVID-19 pandemic: every year acute respiratory illnesses, such as colds and influenza, cause an estimated 18 billion upper airway infections and 340 million lower respiratory infections, resulting in more than 2.7 million deaths and economic loses of billions of dollars (Troeger at al., 2015; Vos et al., 2016). So far, no science-based guidelines exist based on: (i) quantitative knowledge of virus-laden aerosols from human expiration; (ii) exposure and infection risk models; and (iii) the intersection of this risk with typical indoor parameters of buildings and transport options
Improving the resilience of Australian indoor environments
To fulfil the aim of the project, the specific objectives that will be addressed are:
- Expand knowledge of virus-laden aerosols from human expiration, in terms of their size distribution, viral content, relationship with the viral content of expiratory fluids, and infectivity as a function of temperature and relative humidity.
- Advance quantitative methods of risk assessment of indoor infection transmission considering physical (size distribution) and biological (virus survival) characteristics of virus-laden aerosols and the characteristics of the indoor environment.
- Apply the risk assessment method to develop appropriate engineering approaches to minimise the risk of indoor airborne infection transmission in the Australian context. The elements of engineering controls to consider are ventilation, air flow distribution, air conditioning, air cleaning and operation of facilities.
- Develop practical guidelines and tools applicable to: (i) the Australian public building stock and the different climatic zones of the country; (ii) specific environments and practices, including general areas of health care facilities, and indoor gatherings for work and leisure in singing and performing arts facilities; and (iii) transport facilities and vehicles where operational characteristics can be designed to achieve a balance between density of users, quality of service, and cost.