The Department of Health is monitoring the first Middle East Respiratory Syndrome cases reported in Korea.
They involve a married couple, and another man who had been in contact with the husband.
The 68-year-old husband had visited Bahrain and returned to Korea via Qatar. His wife did not travel with him, but had taken care of him on his return.
The other man, aged 76, was in the same hospital room as the husband and has now also tested positive for the virus.
As Ramadan will begin in mid-June, the department reminded pilgrims preparing to go to Saudi Arabia for Umrah to stay vigilant against the disease.
Travel agents organising tours to the Middle East are also advised not to arrange camel rides and activities involving the animals which may increase the risk of infection.
