Tran Dac Phu, chief of the Department of Preventive Health under the health ministry, was quoted as saying in news website VietNamNet that they are keeping a close watch on the virus and strengthening preventive measures.
People are still required to go through temperature screenings when entering Vietnam, and those who are from MERS-stricken places including the Middle East and the Republic of Korea have to fill in medical declaration forms, he said.
Since the Republic of Korea announced the outbreak of MERS on May 20, Vietnamese health authorities have isolated 96 people with its symptoms, but all tested negative later.
The latest case was a 74-year-old Korean tourist who came to Vietnam with his wife on June 24. He fell sick on July 4 and came to a hospital in the central city of Hue for a check-up the same day, news website VnExpress reported.
He was sent to isolation on the same day, while Hue authorities rushed to review all the places he had visited and people he had contacted with. But his test results confirmed that he did not contract the virus.
Although many people dismissed the ministry's measures as "overreacting," they were meant to prevent the virus from entering Vietnam, or to contain it from spreading, Phu said.
MERS falls in the same group of viruses as the common cold and severe acute respiratory syndrome (SARS), which killed 800 people around the world in 2002-03.
The virus, first reported in Saudi Arabia in 2012, causes symptoms like cough, fever and shortness of breath, and is highly fatal – 36% of MERS patients have died, according to the World Health Organization (WHO).
As of July 1, WHO said, it has been notified of 1,357 laboratory-confirmed cases of infection, including at least 484 related deaths.
In the Republic of Korea, 184 cases have been reported, including 33 deaths.
No vaccines or treatment is available for MERS, whose route of transmission still remains unknown, though most cases are attributed to human-to-human infection, WHO said.