Genetic traces have already been found in samples of frozen food, but no live virus has been isolated before. “It has been confirmed that contact with outer packaging contaminated with the novel coronavirus can cause infection,” the agency said in a statement on its website, without specifying where the batch of frozen food came from.
China, which until the Qingdao epidemic had recorded no new local cases in 55 days, was one of the few countries to report possible transmission through frozen foods. When Beijing had a second outbreak in June after the virus was largely contained, officials suggested the new cluster could come from imported salmon.
The US Centers for Disease Control and Prevention said there was no evidence that “food handling or consumption is associated with Covid-19.” New Zealand has ruled out the possibility that one of its first infections occurred in a cold storage facility.
In August, China increased inspection requirements for imports of frozen products after traces of the virus were found on frozen chicken wings from Brazil. Researchers have also detected the virus on imported shrimp and other frozen seafood.
The CDC did not say whether the outbreak in Qingdao was caused by the packaging of frozen food. The outbreak, the first locally transmitted case in nearly two months, has been attributed to two dockworkers initially diagnosed as asymptomatic, who are believed to have infected 12 other people in a hospital.It was not clear whether dockworkers contracted the virus from the packaging of frozen foods. Still, the CDC has warned those who handle frozen goods not to have direct contact with the goods.
The CDC said there had been no cases of consumers contracting the virus and that such risk was low. But some residents have started calling for a temporary ban on imports of frozen products.
The CDC said that out of a total of 2.98 million food packaging samples, researchers found 22 samples that tested positive.