Difficulties arise

Beicai, which boasts high-class buildings and urban villages such as Lianqin, covers nearly 24 square kilometers. The town houses Shanghai's largest farming market and a range of modern businesses.

According to China's sixth population census in 2010, a total of 277,490 people were living in Beicai－more than 155,000 of them migrant workers.

Shen Zaiyuan, head of the Lianqin village committee, said about 80 percent of his villagers are tenants, adding that they mainly work in the farming and logistics industries in Shanghai.

He said he was surprised by the speed at which the Omicron variant of COVID-19 spread, adding that an inferior living environment and complicated population structure initially posed difficulties in fighting the outbreak.

"Some villagers may have been infected before Pudong－the area east of the Huangpu River that was locked down at the end of March," Shen added.

Data from the town's anti-epidemic team show that more than 2,600 people in Beicai were infected on April 12－more than 400 of them living in Lianqin.