BSG-WP-2021/041 Version 2.0 (25 January 2022)

China suffered three large-scale multi-province outbreaks driven by the Delta variant in the second half of 2021. Although they spread to more than ten provinces, all outbreaks were effectively controlled under what Chinese public health authorities describe as the “dynamic clearance” strategy. More recently, the spread of the Omicron variant has brought new challenges. Drawing on the Oxford COVID-19 Government Response Tracker (OxCGRT)’s Chinese subnational data, this paper investigates patterns in government responses to the Delta waves and the threat of Omicron variant and trends in vaccination and international travel policy in China.

The authors find that Chinese provinces have implemented fewer high-cost policies and improved the precision of measures during the Delta waves, though the emergence of the new Omicron variant saw an increase in restrictions on movement between areas. The trend towards more targeted measures is clearer in the provinces with experience of several rounds of Delta outbreaks and continues even local transmissions of the Omicron variant have appeared in China at the beginning of 2022. Meanwhile, with vaccination coverage increasing steadily, some entry restrictions have been relaxed in China, though they remain relatively strict compared to other countries.

For the previous version see BSG-WP-2021/041 (June 2021)

Summary

• Five major waves of COVID-19 outbreaks have hit China since the beginning of 2021, tied to imported sources. The second, third, and fourth surges were caused by the Delta variant, two of which spread to more than ten provinces, and both the Delta and Omicron variants spread across provinces during the latest wave.
• In coping with the Delta variant, China has maintained the policy target of “dynamic clearance”, aiming to halt all community transmission of COVID-19, while the response patterns have gradually transitioned along five stages through 2021 and into 2022: 1) widespread preventative measures in January 2021 in anticipation of greater mixing during the Chinese New Year season, 2) A relatively low baseline level of prevention and control measures from March to June, 3) A reactive response in July to the Delta variant, 4) relatively high baseline prevention and control measures from August to October, and 5) more targeted measures in November and December. Overall, the peak stringency of China’s control measures in 2021—when the highest number of restrictive measures affected the largest population—came with the first Delta wave in summer 2021, though specific geographic regions saw more stringent measures in later waves. Facing the transmission risk of the Omicron variant at the beginning of 2022, China continues to implement dynamic clearance through largely targeted responses.
• Looking at individual policies, the number of provinces mandating stay-at-home measures in response to the most recent Omicron wave is similar to previous waves in 2021, though a number of local governments have also adopted more targeted restrictions at the micro-scale. We also see a larger number of restrictions on movement between areas and requirements around face masks.
• Apart from Non-Pharmaceutical Interventions (NPIs), China has fully vaccinated more than 85% of people, and more than 0.33 bn (23%) people have received booster shots by 6 January 2022. The government is now working to promote booster shots further.
• While the vaccination coverage increases steadily, China has gradually relaxed some entry restrictions, but it retains restrictive controls on international travel compared to most other countries.