Shanghai’s five locally transmitted COVID-19 cases, reported on Friday and Saturday, have been confirmed as the Delta variant, the city health authorities said yesterday.
All the patients were staff servicing foreign cargo aircraft at Pudong International Airport.
After genetic sequencing tests and analysis by the city’s disease control and prevention center — and confirmed by the national center — they were found to be infected by the hyper-contagious Delta variant.
They were infected because they were exposed to people or environments bearing the overseas virus due to their cursory pandemic prevention activity, the authorities said. They had no connection with recent outbreaks in other parts of the country.
They also had no contact history with people from high- or medium-risk regions from other cities, no travel history to those areas, and no contact with the cold chain before they were found infected, according to the center.
All of them had received two doses of the COVID-19 vaccine and were found to be positive during regular nucleic acid tests.
All people related to or close contacts of the five cases had been tested twice — and were negative — by yesterday morning.
Shanghai reported six new local COVID-19 cases last week but no more local cases were found after Saturday.