Drs. Guan and Peiris began collaborating at The University of Hong Kong in the aftermath of the H5N1 avian flu outbreak in Hong Kong. They initiated seminal studies of the underlying causes of H5 virus pathogenicity, the evolution of the H5N1 virus, and developed a highly effective monitoring and surveillance program of avian and swine influenza strains. Through their research Guan and Peiris established that live poultry markets in southern China and Hong Kong were the source of the virus spreading to humans, where it exhibited up to 60% lethality in infected persons. This work led to the temporary closure of the live poultry markets and cessation of animal to human transmission. Their subsequent work established new protocols for periodic live poultry market closures, emptying markets of poultry overnight to reduce virus amplification within these markets and the appropriate use of poultry vaccines to protect both poultry and people in Hong Kong from H5N1 infections. They have made major contributions towards understanding the emergence, transmission, epidemiology and pathogenesis of highly pathogenic avian influenzas including H5N1, H9N2, H6N1, H7N9, H5Nx and others and have provided evidence-based options for control of avian influenza viruses in Asia.
In 2003, following the emergence of novel coronavirus, SARS (severe acute respiratory syndrome) in China, Peiris led the team that first identified the virus responsible for the syndrome, the SARS-CoV-1 coronavirus, elucidating its pathogenesis, transmission, and quickly developed a diagnostic test which was then shared internationally. Meanwhile, Guan’s team identified the human infectious source and zoonotic interface of SARS in the wild animal markets in Guangdong, China in 2003 and identified the human infectious source of MERS (Middle East Respiratory Syndrome) in Saudi Arabia in 2015. Guan’s research accelerated advocacy of the closure of wild game animal markets, averting a potential recurrence of SARS in 2004.
Guan and Peiris’ investigations into the emergence and evolution of animal influenza H5 strains (and other H and N subtypes) and their role in identifying the SARS coronavirus, mode of transmission, risk factors, virus infectivity and period of infectivity, and identifying the original animal source were critical in the successful response to the outbreak.
In the case of SARS, which was causing up to 10% lethality in infected persons, their open sharing of information with the World Health Organization (WHO) and broader international community directly resulted in the rapid control of the disease. The establishment of the role of wild game animal markets in the transmission of the virus was pivotal in the decision by local Guangdong authorities to discontinue such markets to prevent future outbreaks of this or another emerging zoonosis. The isolation and characterization of the causative agent of SARS as a novel coronavirus and quick development of a diagnostic test of the virus in humans directly influenced public health policy to effectively monitor and control the spread of the disease.
Guan and Peiris’ comprehensive strategies for surveillance, monitoring, identifying the human infectious source, investigation, diagnosis and control of emerging infectious disease outbreaks continue to provide critical guidance and insight for countries throughout Asia and the world, including the 2009 swine flu pandemic, Middle East Respiratory Syndrome (MERS), and the COVID-19 pandemic.