The virus tested positive both inside and outside the shrimp packaging (also called shrimp), the China General Administration of Customs said . The samples came from three Ecuadorian plants and imports of those processors will be suspended, the agency said.

The test result does not mean that the virus is contagious, but rather reflects loopholes in companies' food safety regulations, said Bi Kexin, who heads the food import and export security bureau in the department of customs. Customs will further strengthen control of the origins of imported cold chain foods.

China noted last month that imported salmon may have been the source of the new Covid-19 outbreak in Beijing, prompting a boycott of the fish as supermarkets removed the product from their shelves.

China also began massive tests of cold food imports at ports and blocked shipments of meat plants abroad that reported infections among workers.

Evidence indicates that the virus is extremely unlikely to be transmitted through food, said Gorjan Nikolik, associate director of seafood at Rabobank. It is a typical food alert, he said. I don't think it will last long.

Chinese authorities agree with world experts about the low risk that imported food poses in transmitting the virus, but this has raised confusion abroad about why China testing and suspending shipments.

The tests are an important measure to avoid the risk of the virus being transmitted from imported cold chain food channels, Bi said. "t is a necessary measure to protect people's health and does not disrupt habitual international trade.

Employees in some countries continue to work even after becoming infected with the virus, increasing the risk of food contamination, Bi said. Because there are epidemic cores at some overseas facilities, China suspended meat imports from a total of 23 plants, including Brazil, the United Kingdom, the United States and Germany, Bi said.