It didn't. There are 300 to 400 new infected every day. The total would be much higher except that China blockaded all cities around Wuhan with armed guards, quarantined everyone in Wuhan including locking people in the apartments, shut down practically all businesses, built new hospitals to warehouse the sick infected, banned travel to and from Wuhan.
They literally bulldozed streets overnight and welded people into high rises. We all saw the videos until CCP stepped in.
You didn’t mention they cut their total industrial output by half in one month—and crashed the world’s stock markets.
Other than that, China didn’t do much... ;-)
China is lying to prevent economic collapse and social chaos.