Customers shop at a Sam's Club warehouse store at Beicai Town in Pudong New Area, east China's Shanghai, May 2, 2022. Large retail companies in Shanghai have started to reopen their supermarkets amid the recent COVID-19 resurgence. (Xinhua/Chen Jianli)

A customer walks past a Sam's Club warehouse store at Beicai Town in Pudong New Area, east China's Shanghai, May 2, 2022. Large retail companies in Shanghai have started to reopen their supermarkets amid the recent COVID-19 resurgence. (Xinhua/Chen Jianli)

Customers check out at a Sam's Club warehouse store at Beicai Town in Pudong New Area, east China's Shanghai, May 2, 2022. Large retail companies in Shanghai have started to reopen their supermarkets amid the recent COVID-19 resurgence. (Xinhua/Chen Jianli)

Customers shop at a Sam's Club warehouse store at Beicai Town in Pudong New Area, east China's Shanghai, May 2, 2022. Large retail companies in Shanghai have started to reopen their supermarkets amid the recent COVID-19 resurgence. (Xinhua/Chen Jianli)

Customers shop at a Sam's Club warehouse store at Beicai Town in Pudong New Area, east China's Shanghai, May 2, 2022. Large retail companies in Shanghai have started to reopen their supermarkets amid the recent COVID-19 resurgence. (Xinhua/Chen Jianli)