A sample of frozen chicken wings imported into the southern Chinese city of Shenzhen from Brazil has tested positive for coronavirus, the city government has said, raising fears that contaminated food shipments could cause new outbreaks.
Local disease control centres tested a surface sample taken from the chicken wings as part of routine screenings carried out on meat and seafood imports since June, when a new outbreak in Beijing was linked to the city's Xinfadi wholesale food centre.
The discovery came a day after traces of the coronavirus that causes COVID-19 were found on the packaging of frozen shrimp from Ecuador. China has been stepping up screenings at ports amid the concerns over food imports.
Shenzhen's health authorities traced and tested everyone who might have come into contact with potentially contaminated food products, and all results were negative, the city's notice said.
The Brazilian embassy in Beijing did not immediately respond to a request for comment.
"It is hard to say at which stage the frozen chicken got infected," said a China-based official at a Brazilian meat exporter.
The Shenzhen Epidemic Prevention and Control Headquarters said the public needed to take precautions to reduce infection risks from imported meat and seafood.
In addition to screening all meat and seafood containers coming into major ports in recent months, China has suspended some meat imports from various origins, including Brazil, since mid-June.
Li Fengqin, who heads a microbiology lab at the China National Center for Food Safety Risk Assessment told reporters in June the possibility of contaminated frozen food causing new infections could not be ruled out.
Viruses can survive up to two years at temperatures of minus 20 degrees Celsius, but scientists say there is no strong evidence so far the coronavirus that causes COVID-19 can spread via frozen food.