【明報專訊】Cases involving various COVID-19 variants have cropped up sporadically across mainland China once again after the beginning of the new year. For several consecutive weeks, the number of new infections reached three-digits, and it was only yesterday (16 January) that the figure returned to double-digits for the first time. Omicron is pervasive—new cases have already been detected in 14 provinces and cities, and there has been a surge in the number of asymptomatic infections. The Winter Olympics are about to begin, so is the Spring Festival travel rush, both of which will sharply increase the movement of people and size of crowds, making the battle against the pandemic even tougher. However, the general policy of aiming for ''dynamic zero COVID'' remains unchanged, and it is even more necessary to continuously optimise anti-epidemic measures according to changes in the situation. Only by varying the tactics from time to time can the pandemic be nipped in the bud.