Two of China’s largest port cities, Shanghai and Tianjin, have announced locally transmitted coronavirus infections, renewing worries about whether the country can continue to keep out the virus after coming close to eradicating it over the summer.
Tianjin said on Friday that it had discovered four cases, all in its port area. Shanghai said on Saturday that an airport cargo security officer and his wife, a nurse, had both been infected. The Shanghai cases come less than two weeks after an air cargo worker at the same oceanfront airport, Pudong International, tested positive.
Chinese cities respond to even a single case with extensive coronavirus testing programs. Within hours of the two new cases in Shanghai, local authorities said they had tested six family members of the couple and 80 other close contacts, all of whom were negative. Another 8,120 people in the area were also tested, with more than half of these tests already processed and all negative, officials added.
In Tianjin, the residential community with four new cases was completely sealed off by the authorities. Other neighborhoods nearby, which have people who had been in contact with residents of the sealed-off community, were put under mandatory testing programs, with schools and public places closed and travel restricted.
The Chinese government has repeatedly warned that the virus could re-enter the country on food or other shipments of chilled or frozen goods. Tianjin and Shanghai officials have emphasized that their recent cases were concentrated in areas that handle such goods.
The U.S. Centers for Disease Control and Prevention has said that the virus is primarily airborne. Experts generally say that while it can be transmitted through frozen food and contaminated surfaces, the likelihood is exceedingly low.
National and municipal officials in China have been quick this autumn to blame foreign countries for virus outbreaks on their soil. In addition to extra testing of imported food, the government has made it difficult for Chinese nationals to return from overseas and banned the entry of foreign visitors and many longtime foreign residents.
Amy Chang Chien contributed research.