As of Tuesday, five fishing boats at fishing port at Qingdao, East China's Shandong Province have brought back about 35 tons of shrimp and fish to boost market supply. Photo: cnsphoto

As of Tuesday, 3 packages of 2,750 samples of frozen South American white shrimp imported from Ecuador have tested positive for COVID-19 in Southwest China's Yunnan Province, while the shrimp itself and contacts tested negative, Yunnan health commission said on Thursday.

Six tests on the packaging and interior wall of the containers from three Ecuadorian shrimp producers tested positive on July 3, on which the Chinese customs made a statement saying the three companies' container environments and outer packaging had risks of coronavirus contamination, said the General Administration of Customs, National Health Commission and State Administration for Market Regulation on Friday.

A nationwide screening began following this statement. As of Sunday morning, 476 samples of imported seafood products collected in Shanghai showed negative results. Packages tested positive in a frozen storage facility in Southwest China's Chongqing Municipality on Tuesday, according to local authorities. Other places have also conducted nucleic acid tests on Ecuadorian shrimps and outside packaging.

Approximately 78 tons of Ecuadorian white shrimp have been recalled and sealed up in East China's Zhejiang Province, per Zhejiang market regulator on Saturday.

China is the biggest importer of Ecuadorian white shrimp. In April, China imported 47,000 tons of white shrimp from Ecuador, accounting for about 80 percent of Ecuador's national exports, according to National Chamber of Aquaculture of Ecuador.

Ecuador shrimp exports in Q1 2020 Graphics: GT

There are about 3,800 white shrimp farms across the country, with an area of 18,500 hectares, making aquaculture a big part of the Ecuadorian economy, reports showed.

Ecuador has promised China that it will perform the "necessary procedures" to guarantee the safety of exported frozen shrimps, the Embassy of the Republic of Ecuador in China told Global Times on Wednesday.