(Bloomberg) -- China has suspended imports of dragon fruit from Vietnam following the detection of coronavirus, temporarily halting a $1 billion market as Beijing continues its vigorous testing of inbound food shipments for virus risk.

Imports of the tropical fruit have been suspended for a week beginning Wednesday, Vietnam’s trade ministry said on its website. Authorities in China’s Guangxi region, bordering Vietnam, informed the ministry of the halt after the coronavirus was found on packaging and cardboard boxes shipped from Quang Ninh province. 

“It is quite a rare incident,” said Dang Phuc Nguyen, general secretary of Vietnam Vegetable and Fruit Association. “Workers at fruit-processing factories are required by the government to stay on site, test against Covid-19 regularly, and they are vaccinated.”

China is the top destination for Vietnamese dragon fruit -- representing over 80% of total shipments and amounting to $1 billion a year, according to Nguyen. Dragon fruits make up one third of Vietnam’s exports of vegetables and fruits, which was $3.27 billion last year, he said. 

The halt is the latest blow to Vietnam’s fruit trade with China, which was already seeing a decline in exports amid land transport congestion, tighter border controls and increased domestic plantings in China, said Nguyen. 

China has been vigilantly testing imported foods -- particularly meat and seafood -- for traces of the virus, despite the World Health Organization saying there’s no evidence of people catching the virus from food and food packaging. Beijing, which is facing a Covid-19 outbreak in Fujian province, has been on high alert for any potential spread of the virus ahead of major holidays. 

The country has also suspended other fruit shipments recently, including Taiwan pineapples that was seen as a political move amid deteriorating cross-strait relations. China turned away cherries earlier this year after authorities found the virus on the inner packaging of the fruit found in Jiangsu province.

Guangxi officials said the dragon fruit halt will extend for another week if coronavirus is detected again, using the PCR testing method, on the packaging of dragon fruits or any products shipped from Vietnam, according to the ministry. The third detection will result in a four-week suspension. 

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