HKU Engineering-led team to study methodology and practices on detecting COVID-19 virus for sewage

A cross-disciplinary team led by Professor Tong Zhang of the Department of Civil Engineering and supported by the “COVID-19 Action Seed Funding” of the Faculty of Engineering at the University of Hong Kong, has received funding from the government’s Health and Medical Research Fund to develop a methodology for the detection and monitoring of SARS-CoV-2 in sewage to supplement the overall community surveillance system. The study will start in mid-October.

In the past few months, the presence of SARS-CoV-2 nucleic acid in sewage was reported in various countries and regions. These occurrences may even be dated back to before any awareness of virus circulation in those communities. The recent development in sewage testing for SARS-CoV-2 may lead to new measures for public health surveillance, for early detection of COVID-19 emergence. However, there is currently no standardised method for surveying COVID-19 in municipal sewage. The key experimental steps in the pre-treatment of sewage samples, as well as the detection and quantification processes in the context of Hong Kong, have yet to be systematically evaluated and optimised.

Since April 1, the cross-disciplinary team led by Professor Zhang has been working to optimise the protocol, validating the methodology and conducting preliminary tests with spiked samples. They have developed methods suitable for detecting SARS-CoV-2 in sewage in Hong Kong by using centrifugal filter for pre-concentration.

With the strong support from the Drainage Services Department and Environmental Protection Department, the research team has been conducting a couple of projects (including one funded by Health and Medical Research Fund to be kicked off in October) on the surveillance of SARS-CoV-2 in the sewerage network. The data from sewage can be used to inform the presence and spread of the virus in district-specific communities, even when individuals’ data are not yet available. The results could complement current clinical and laboratory surveillance effort.

Professor Zhang said: “Now is a good time to establish the general principles and explore suitable practices for the feasibility of a long-term sewage monitoring methodology to proactively identify and respond to future outbreaks of COVID-19 in Hong Kong.”

The team comprises five experts in the field of environmental microbiome and public health. Professor Tong Zhang is the Principal Investigator of HKU’s Environmental Microbiome Engineering and Biotechnology Laboratory. He is a pioneer in applying DNA and RNA technology to study environmental microbiome and has more than 20 years’ experience in the field of environmental microbiology. He is also a member of the International Water Association (IWA) Task Force Group on COVID-19. Other team members include Professor Leo Lit Man Poon, Professor Malik Peiris, Professor Gabriel Leung, and Dr. Hein Min Tun of the School of Public Health, Faculty of Medicine of HKU. Professors Poon and Professor Peiris lead the WHO Reference Laboratory for COVID-19 diagnostics at HKU and are well-known for their extensive expertise in developing testing methods for emerging virus of public health concerns, including SARS-CoV-2. Professor Gabriel Leung is the Dean of Li Ka Shing Faculty of Medicine at the University of Hong Kong, and an expert on infectious disease epidemiology.