Tianjin launched emergency prevention action on Sunday after the city's disease control and prevention center confirmed a new COVID-19 case, but authorities said that the case is not likely to stir an outbreak in the city.

The patient is a 38-year-old man who works on a loading dock at Hailian Frozen Food Co in the municipality's Binhai New Area. He tested positive on Sunday after he was found to have handled a shipment of frozen pork on Wednesday.

Samples of the outer packing of the pork, which arrived in Tianjin on Oct 19 from Germany, tested positive for coronavirus on Saturday after being sent to Dezhou, Shandong province, triggering a test of its contacts, the Tianjin Centers for Disease Control and Prevention said.

In a preliminary investigation, only the loading dock worker and an environmental sample from a cold storage doorknob at the company tested positive so far, the center said at a news conference on Sunday.

Eleven people in Tianjin worked in the same area as the patient and they all tested negative for the virus. Eight colleagues of the patient shared the same apartment with him. They are under medical observation and their nucleic acid tests all came back negative, said He Peng, a spokesman for the Tianjin CDC.

The cold storage facility has been sealed off. Disinfection has been completed in the working and living areas concerned.

On Sunday morning, samples of 156 people in the same community were collected for nucleic acid testing and all came back negative. The remaining residents of the community are still waiting for tests, and the results will be released later, said Liang Chunzao, deputy director of Binhai New Area.

Liang added that large-scale nucleic acid testing will be carried out for workers of all cold storage and cold-chain companies in the coastal Binhai New Area over the next three days.

Hou Jinpo, deputy head of Tianjin Customs, said the authority will strengthen its risk protection efforts－including disinfection nuclide acid testing－and information disclosure.

During the year's first three quarters, Tianjin imported 2.17 million tons of food.

Meanwhile, the municipality received a report from Taiyuan, Shanxi province, on Saturday that a sample of outer packaging from frozen beltfish imported from India, via Tianjin, had reportedly tested positive for the novel coronavirus.

By Sunday's news conference, tests of people who had contact with the beltfish packing in Taiyuan have all returned negative.