People buy vegetables in a supermarket in Qingdao, east China's Shandong Province, Jan. 29, 2020. To ensure the supply of vegetables during the fight against novel coronavirus in Qingdao, the local government has put vegetable reserves in the market. (Xinhua/Li Ziheng)

People buy vegetables in a supermarket in Qingdao, east China's Shandong Province, Jan. 29, 2020. To ensure the supply of vegetables during the fight against novel coronavirus in Qingdao, the local government has put vegetable reserves in the market. (Xinhua/Li Ziheng)

People buy vegetables in a supermarket in Qingdao, east China's Shandong Province, Jan. 29, 2020. To ensure the supply of vegetables during the fight against novel coronavirus in Qingdao, the local government has put vegetable reserves in the market. (Xinhua/Li Ziheng)

People buy vegetables in a supermarket in Qingdao, east China's Shandong Province, Jan. 29, 2020. To ensure the supply of vegetables during the fight against novel coronavirus in Qingdao, the local government has put vegetable reserves in the market. (Xinhua/Li Ziheng)

People buy vegetables in a supermarket in Qingdao, east China's Shandong Province, Jan. 29, 2020. To ensure the supply of vegetables during the fight against novel coronavirus in Qingdao, the local government has put vegetable reserves in the market. (Xinhua/Li Ziheng)