Medical staff members work at the Pudong airport  Photo: VCG

The latest five domestically transmitted COVID-19 cases reported in Shanghai Pudong International Airport were possibly infected via personnel or environments contaminated by the coronavirus imported from overseas, Shanghai authorities announced on Monday, after five patients were found in the airport within two days last week. 

They were infected with the Delta variant, from sources unlike those in recent local domestic cases in cities like East China's Nanjing and Central China's Zhengzhou, "neglect of appropriate protection" also played a role, according to the local authorities. They hadn't come into contact with imported cold-chain products or patients from other provinces 14 days before they were found to have been infected with the virus. 

Just like how a nurse became infected in a Shanghai hospital recently, the five persons were infected probably by "neglect of protection" when they were exposed to personnel or environments "contaminated by the coronavirus imported from overseas," said the authorities.

Shanghai has quarantined 143 persons who were close contacts of the five local patients found in Pudong airport on August 20 and 21, all of whom returned negative results after two rounds of nucleic acid tests. A total of 80,966 people related to the five cases were tested twice and all returned negative results, said the authorities.

The five patients all received COVID-19 vaccinations and were working at the international cargo flight regions, according to the authorities. An expert suggested that antibody detection is necessary for frontline workers after the incident.

Currently, there are still five medium-risk regions in Shanghai, and the rest of the city is low-risk.