Medical Faculty News v25i1

Tracking the Animal Origins of Emerging Viruses The past two decades have seen outbreaks of emerging viruses that jumped from animals to infect humans, such as the H7N9 bird flu, SARS, swine flu (H1N1) and the Middle East Respiratory Syndrome (MERS). Work by Dr Tommy Lam Tsan-yuk , Assistant Professor of the School of Public Health, has enriched our understanding of these viruses. Dr Lam focuses on the animal-human interface of emerging infectious diseases and uses a bioinformatics approach to trace the ecology, evolution and epidemiology of these new pathogens. He did his undergraduate and postgraduate studies at HKU, then went overseas for post-doctoral training before returning to HKU in 2013 – just in time for the H7N9 influenza outbreak, which had a high mortality rate. Dr Lam worked with Professor Yi Guan’s research team to conduct a large-scale genetic analysis of the virus. His work showed that the virus jumped from aquatic birds to domestic ducks, and from there to chickens where they reassorted into viruses that could infect humans. Chickens in live poultry markets were shown to be the main source of human infections of H7N9. “We elucidated the ecological pathway and also found the evolutionary pathway of how the virus changed in the process from infecting animals to infecting humans,” he said. He made similar contributions in the case of the MERS virus, which was first reported in Saudi Arabia in 2012 and saw a large outbreak in Korea in 2015. Through intensive investigations in the Middle East, Dr Lam and his colleagues found that the virus had been circulating among dromedary camels in Saudi Arabia. Using genetic analysis, he also showed that the virus had evolved into five distinct lineages, one of which was the source of outbreaks in humans in Saudi Arabia and Korea. Recently, Dr Lam was awarded a grant from the National Natural Science Foundation of China Excellent Young Scientists Fund (Hong Kong and Macau) for a project to build a database of the genome, phenotype and epidemiology of major emerging zoonotic viruses, including H7N9 and MERS viruses. This will be the first time that all the information of these viruses will be unified – currently it is published in different places – and it will enable scientists and public health officials to identify and respond quickly to new outbreaks and improve prevention and control. “By integrating this data, we can study the genetic determinants for each genotype and track emerging pathways and transmission routes. When there is a new outbreak, for example of MERS, we will be able to compare new and published sequences to understand and predict its infectiveness and transmissibility,” he said. The results and methods will be widely available for the biggest impact. “Other laboratories that may not have much bioinformatics capacity will be able to make use of this toolbox without necessarily having to go through our labs,” he added. 23 Medical Faculty News