Epidemic control staff are checking the health codes of travelers at a railway station in Shanghai on January 1, 2022. Photo: VCG

Shanghai has strengthened control measures on community health monitoring of inbound travelers after five cases that tested positive for COVID-19 were all related to an imported asymptomatic case, the authorities said on Thursday.

Shanghai reported two local confirmed COVID-19 cases and three asymptomatic infections that are all related to one imported asymptomatic case reported on Tuesday, Shanghai authorities announced during Thursday's press briefing. A property in Shanghai's Jing'an district, where the confirmed patients worked, was put on medium-risk level for COVID-19. 

Shanghai has adopted a "14+7" health management measure for inbound personnel, meaning that travelers from overseas have to be in central quarantine for two weeks with an additional week of home isolation after entering the city.

The authorities reiterated that everyone must obey the rules during the seven-day self-monitoring period. People are not allowed to take public transport, gather for meals and dine in the restaurants, take a walk in the community, walk pets, and go out to watch movies, plays and exhibitions. Receiving visitors, hosting parties, lectures and other crowd gathering activities are not permitted. 

Those in isolation are not allowed to visit places where people gather, such as shopping malls, supermarkets, office buildings, restaurants and places with closed environment like theaters, playing rooms and KTVs, according to the authorities.

Serious punishment measures will be taken in accordance with the law against those who violate the regulations, including legal liability investigation, reporting to the municipal public credit information platform and public supervision, the authorities said on Thursday.   

The imported asymptomatic patient is a Chinese citizen studying in the US who arrived at Pudong International Airport on December 21. The patient tested negative for COVID-19 four times during the two-week quarantine but tested positive on the last day without symptoms during seven-day self-health monitoring.

As of 7 pm on Thursday, 304 close contacts of the five cases were put under quarantine and their nucleic acid test results returned negative.

A total of 30,783 residents have been tested, with 30,128 samples testing negative for COVID-19, while the rest remain under testing. A total of 1,626 environmental samples have been tested, with 34 samples, all from the patients' home, coming back positive for the virus.