A female Russian tourist suspected of carrying Middle East Respiratory Syndrome (MERS) has been quarantined in the Central Highlands province of Lam Dong for further observation, health authorities said on Tuesday.

The foreign woman and her boyfriend, who accompanied her on a tour, have been isolated at the Lam Dong General Hospital in Da Lat City, said Dr. Dong Si Quang, head of the provincial Health Department’s Division for Medical and Pharmaceutical Affairs. Before arriving in the Southeast Asian country, the two travelers had transited through Dubai in the United Emirates Arab, and Bangkok, Thailand. Both countries have been infected with MERS. The 24-year-old woman, whose name has not been revealed, arrived at Hoan My General Hospital in the province yesterday morning for a check-up after she developed a fever and sore throat, Dr. Quang said.

After receiving a report on the woman’s health condition from this hospital, the provincial Health Department requested that she be transferred to the Lam Dong General Hospital for treatment in isolation.

Health officials also asked her boyfriend to be quarantined along with her at the same infirmary. The tourist and her boyfriend arrived in Vietnam on June 20 and visited Da Lat two days later. The provincial Center for Preventive Healthcare already took a sample of medical waste from the woman and sent it to the Ho Chi Minh City Pasteur Institute for testing. MERS, which is caused by the Coronavirus, has an incubation period of two to 14 days, during which infected people will show no signs of infection, said Dr. Tran Dac Phu, head of the Vietnamese health ministry’s Health Preventive Department. The disease transmits from ill people to others through close contact and has a mortality rate as high as 40 percent, Dr. Phu warned. Vietnam has yet to detect anyone infected with MERS, which first appeared in Saudi Arabia in 2012, but the virus may penetrate the Southeast Asian country via people who come from areas affected by the epidemic, including Asian countries near it such as China, South Korea, and Thailand. Vietnam's health authorities have requested that all border gates, including the international airports in Hanoi and Ho Chi Minh City, tighten medical quarantine procedures to detect signs of the disease from international visitors, especially those from MERS-hit areas. So far, Vietnam has had dozens of suspected MERS cases, tests on which have all proven negative, the ministry said. MERS has up to now caused 1,330 cases in 26 countries and killed over 470 patients, according to the World Health Organization.