South Korea reported four new cases of Middle East Respiratory Syndrome Wednesday but no additional deaths from the disease.

The latest cases raised the total number of people diagnosed with the disease to 179, with the death toll remaining at 27, according to the Ministry of Health and Welfare.

Three of the four new patients had been in isolation as suspected cases, while the source of infection for the fourth patient was unclear, according to ministry officials.

The new cases include a patient from Seoul's Samsung Medical Center, which has been blamed as an epicenter of infections and has voluntarily shut down most of its operations after nearly half of all transmissions occurred there.

A nurse working at a hospital in Gangneung, 237 kilometers east of Seoul, also has tested positive for the virus, according to the ministry

As of Wednesday, the number of people in isolation for possible infection came to 3,103, up from 2,805 on the previous day, marking the first daily rise in six days.

The health authorities said they will extend Samsung Medical Center's partial shutdown without a time limit. The initial shutdown was scheduled to end on Wednesday.

They also said Konkuk University Medical Center in eastern Seoul has also been partially closed as two MERS patients had been admitted there.

Since the country reported its first MERS case on May 20, over

13,000 people have been subject to quarantine with 11,210 released from isolation after showing no symptoms of the disease for more than the known maximum incubation period of 14 days.

Out of the 179 people diagnosed with MERS so far, 67 have been discharged from the hospital following complete recoveries.

MERS is a viral respiratory disease first reported in Saudi Arabia in 2012.

There currently is no vaccine or treatment for the disease that had carried a very high fatality rate of over 40 percent until the outbreak here.

In South Korea, the fatality rate of the disease remains at around 15 percent. (Yonhap)