GENEVA - The World Health Organization said on Thursday it saw no evidence of coronavirus being spread by food or packaging and urged people not to be afraid of the virus entering the food chain.

There is no evidence that food or the food chain is participating in transmission of this virus. And people should feel comfortable and safe 

Mike Ryan, WHO head of emergencies programme

Two cities in China said they had found traces of the coronavirus in imported frozen chicken wings from Brazil and on outer packaging of frozen Ecuadorian shrimp, raising fears that contaminated food shipments might cause a new outbreak. 

“People should not fear food, or food packaging or processing or delivery of food,” WHO head of emergencies programme Mike Ryan told a briefing in Geneva. “There is no evidence that food or the food chain is participating in transmission of this virus. And people should feel comfortable and safe.”

A senior expert of the WHO said on Thursday that although there are some cases suggesting that an individual may have been re-infected with COVID-19, it's still not confirmed.

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Maria Van Kerkhove, technical lead on COVID-19 response at the WHO Health Emergencies Program, told a virtual press conference that some people can have PCR (polymerase chain reaction) positivity for many weeks, not just days, and it doesn't necessarily mean that they are infectious for that long.

According to the WHO expert, false positivity or false negativity may also lead to the result that an individual is tested positive again, but that should not be viewed as re-infection.

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"What we ideally would like is to look at sequencing. If the virus can be isolated, if sequencing can be done, so we can look and see if somebody has been re-infected," she said.