More than 5,000 Chinese workers who returned to Vietnam after the Lunar New Year holiday are being monitored for signs of coronavirus.
They are being isolated in their companies' dormitories and hotels, while suspected infection cases are quarantined at medical facilities.
Vietnam has already quarantined a rural community of 10,000 people near the capital Hanoi over fears that the virus could spread there.
The South-East Asian country declared a public health emergency over the epidemic on February 1 and has banned all flights to and from China.
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