HKUST PPOL Newsletter Spring 2023

Zhu, P., Tan, X., Wang, M., Guo, F., Shi, S., & Li, Z. (2023). The Impact of Mass Gatherings on The Local Transmission of COVID-19 and The Implications for Social Distancing Policies: Evidence from Hong Kong. evaluates the importance of social distancing policies. With an aggregated dataset of epidemiological, city-level meteorological, and socioeconomic data, a Synthetic Control Method (SCM) is used for constructing a ‘synthetic Hong Kong’ from over 200 Chinese cities. This counterfactual control unit is used to simulate COVID-19 infection patterns (i.e., his paper examines the impacts of mass gatherings on the local transmission of COVID-19 and T the number of total cases and daily new cases) in the absence of mass gatherings. Comparing the hypothetical trends and the actual ones, our results indicate that the infection rate observed in Hong Kong is substantially higher than that in the counterfactual control unit (2.63% vs. 0.07%). As estimated, mass gatherings increased the number of new infections by 62 cases (or 87.58% of total new cases) over the 10–day period and by 737 cases (or 97.23%) over the 30-day period. These findings suggest the necessity of tightening social distancing policies, especially the prohibition on group gathering regulation (POGGR), to prevent and control COVID-19 outbreaks. Plos one, 18(2), e0279539. Research Showcase 20