Due to the current Covid-19 outbreak in China, authorities in cities such as Zhengzhou and Haikou are increasing inspections of imported frozen food to prevent the spread of the virus. This action follows claims that the virus can be transmitted through food packaging, a theory that has been disputed by international health authorities like the World Health Organization and the U.S. Centers for Disease Control and Prevention. Despite this, China has been testing cold food shipments for the virus since months and has caused port congestion and long customs clearance delays. The outbreak, caused by the delta variant, has spread to nearly half of China's provinces in just two weeks.