The Chinese city of Xian completely locked down on December 22 and for more than three weeks, people were only allowed to leave for emergencies.

Is Tianjin next?

Here is a look at daily cases in Tianjin, which spiked to 80 today.

Tianjin daily covid case chart

Xian was locked down after 63 locally-transmitted cases and a total of 211 over the prior week.

That compares to 294 for Tianjin over the past week. The population of Xian is 13m compared to 15.6m in Tianjin.

On a straight comparison, we should be seeing a similar lockdown imminently. Of course that ignores particular case dynamics, contained mass outbreaks and contact tracing, which could factor into decision.

It also could signal a change in tactics. Beijing has stopped talking about covid-zero and is now touting 'dynamic clearing' as a strategy. It gives more power to local officials. To me this is an indication of shifting responsibility (and blame) for outbreaks but it could also be signaling more tolerance.

Still, the differences so far are stark and people in Xian must be confused at a different set of rules. People everywhere in Tianjin except one district can continue to move freely, though roads to Beijing and Shanghai have been closed.

The priority was to “minimise the movement of people in the infected areas”, Tianjin officials said Thursday.

Today, Li Hongzhong, the Communist Party secretary of Tianjin said the city needed to “fully promote zero social transmission” and needed to step up contract tracing and testing in “risky areas and population groups to strengthen epidemic risk control and interrupt virus transmission channels”.

That doesn't sound like someone on the verge of locking down the world's fourth-largest port.

Part of that could also be the looming Beijing winter Olympics, which start in 18 days. Tianjin is an hour away from Beijing and is the port of entry for many of the goods for the games. Also note that the first case of local transmission of unidentified origin was found in Beijing yesterday.

At some point China will need to transition to living with covid and how that unfolds is the single biggest x-factor in the global growth picture in 2022.