Dalian File Photo:VCG

The latest outbreak in the Northeast Chinese coastal city of Dalian is likely caused by coronavirus contaminated imported frozen products, according to the local government.

The preliminary investigation result was issued after Dalian analyzed the genomic sequence of all 83 COVID-19 cases dating back to Monday, and found out that they belong to different homology from the previous outbreak in the city. This finding prompted the local government to rule out the possibility of continuous local transmission, and it is not genetically linked to previously reported imported cases and local cases.  Therefore it is concluded that the infection came from outside China, said a Dalian official at a Monday conference. 

Most of those infected are workers at Dalian port, who became infected after carrying items from a Russian cargo ship that were later confirmed to be contaminated with coronavirus.

Those workers then passed the virus to people in a building, widening the scope of the infection.

The new outbreak in Dalian started on December 15, and the city then entered "wartime" mode on December 20 to prevent the further spread of the disease.

Last week, the city announced that it was extending the COVID-19 quarantine period to 21 days from 14 as the new cases in the recent COVID-19 outbreak in the city show a longer incubation period, faster transmission and more complex pattern.

Dalian's earlier outbreak in July which originated from a seafood processing factory, was also suspected to be linked with imported cold-chain products.

Global Times