The world has undergone five waves of COVID-19 pandemics, with a sixth wave likely to be led by China as policies in China begin to relax. We reproduced the multiple Omicron waves in Singapore using a multi-dimensional model. Our model shows that the simulated epidemic curve matches the publicly reported data. And we simulated the Omicron wave after reopening in Xiamen, a city with a population size and age structure similar to Singapore based on Singapore’s experience during Omicron wave. We advocate that cities in China emulate Singapore’s response to the Omicron wave through dynamic PHSMs adjustment, thereby reducing the disease and healthcare system burden.