Jiangxia district residents have been ordered to stay inside their homes or compounds for three days after four asymptomatic Covid cases were detected.
China follows a "zero Covid" strategy, including mass testing, strict isolation rules and local lockdowns.
This has resulted in far fewer deaths than in many other countries.
But the strategy is facing growing opposition as people and businesses continue to face the strain of restrictions.
In Wuhan, a city of 12 million people, regular testing uncovered two asymptomatic cases two days ago.