South Korea reported no additional cases of Middle East Respiratory Syndrome for the 21st consecutive day on Sunday, with the number of patients here remaining unchanged at 186.

No additional fatalities from the respiratory disease have been reported for the past 14 days, leaving the country's death toll unchanged at 36, according to the Ministry of Health and Welfare.

Of the 186 people who have contracted the disease, 12 are still hospitalized while the remaining 138 have been discharged following complete recoveries.

As of Sunday, 11 out of the 12 patients had already tested negative for the potentially deadly disease, according to the ministry. The sole patient who still tests positive has also tested negative in some cases, it added.

Since the country reported its first case on May 20, some 16,700 people have been subject to isolation for possible infection following their exposure to MERS patients.

Most of them have been released after they showed no symptoms of MERS for more than the known maximum period of 14 days for the disease.

As of Sunday, only one person remained in isolation as a suspected case but is waiting for the isolation order to be lifted at midnight.

The government is expected to deliver a message announcing the 'de facto' end to the MERS outbreak this week, although a more official declaration will come later.

Under rules by the World Health Organization, the declaration of an end to an outbreak can be made at least 28 days after the last patient has completely recovered.

MERS is a viral respiratory disease that had a very high fatality rate of more than 40 percent until the outbreak here.

In South Korea, the fatality rate currently stands at 19.4 percent.

The disease was first reported in Saudi Arabia in 2012. (Yonhap)