Unravelling How SARS-CoV-2 Has Been Transmitted

Principal Investigator: Professor Yuguo LI (Department of Mechanical Engineering)

This project is showcased in the inaugural exhibition – Engineering for Better Living in Innovation Wing Two

Project information


How is the emerging new SARS-CoV-Z transmitted? This has been one of the major challenges for effective intervention since the COVlD-19 pandemic emerged in late 2019. Following our continuous environmental studies of infection since 2003 SARS epidemics, our team immediately explored our long-held hypothesis that short-range inhalation transmission might predominate the spread of most respiratory infection.

Novelty of the Project

  1. Our work provided the essential probable evidence for recognizing the airborne transmission of SARS-CoV-2 by the health community in July 2020.
  2. We identified the chimney effect in the drainage stack explained more than 10 vertical COVID-19 outbreaks in Hong Kong.
  3. We identified short-range inhalation transmission of SARS-CoV-Z, which has been recognized by World Health Organization (WHO) and U.S. Centers for Disease Control and Prevention (US CDC).
  4. We redefined transmission routes as inhalation, spray and touch, which has been accepted by US CDC.

Benefit to the Community

  1. Recognition of airborne transmission paves the way for improving ventilation, e.g. in dine-in restaurants in Hong Kong, and for specifying maximum classroom capacity for each of HKU classrooms.
  2. Recognition of short-range inhalation transmission calls for the need of wearing N95 masks by health care workers.
  3. New understanding of vertical outbreaks shows the urgent need for improving and monitoring drainage systems in high-rise housing.
  4. The new concepts of aerosol inhalation, drop spray and surface touch promises easy communication for infection control of respiratory infection.

About the Scholar

Professor Li is the Chair Professor of Building Environment at HKU. His research interests includes city climate/environment, environment studies of infection and indoor environment. He currently also serves as a member of the WHO IPC Guidelines Development Group and WHO Environment and Engineering Control Expert Advisory Panel for COVID-19

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Achievement of the Project

Professor Yuguo Li received one Medal of Honour, and 13 post-docs and students were on the list of Chief Executive’s Commendation for Community Service. Their work was published in Annals of Internal Medicine, Journal of Hazardous Materials etc.

Enquiry / Feedback

Please feel free to give your enquiry / feedbacks to the research team by filling the form (https://forms.gle/XJ8hWfS1qHpDY9hU9). Thank you!