A group of police officers from the Shanghai Jing'an Public Security Bureau are on duty at Shanghai Railway Station, one of the four major train stations in Shanghai, East China.Their main responsibility is to check tourists’ health status and maintain order in the railway station.After they work for 15 days straight in a shift, they will be quarantined for 14 days, which means they will not be able to see their families for nearly a month.(Photos: Yang Hui/GT)