Extraordinary street protests in some Chinese cities and campuses over the weekend put Xi Jinping's controversial approach to the pandemic under the spotlight.
Residents held late-night demonstrations against draconian "zero-COVID" lockdown measures after 10 people were killed in an apartment fire. Protests in China are extremely rare.
Lockdowns are so strict and so prolonged in the Chinese city that residents have taken to social media to complain and joke about a lack of basic supplies.
The coronavirus is "very unlikely" to have started in a Chinese lab but its path from animals to humans needs further investigation, a World Health Organization team said after visiting Wuhan.
Qingdao city officials say no new infections were identified. The extraordinary testing effort followed the appearance of a small cluster of COVID-19 cases centered in a city hospital.