The rapid rise in deaths makes South Korea the location with the largest MERS outbreak outside of the Middle East.
On Saturday a 75-year-old man became the fifth person to die as a result of contacting the MERS virus.
The man was in Seoul hospital along with others diagnosed with the virus prior to becoming ill.
He had been in a Seoul hospital alongside other sufferers when he became ill.
Over 2,300 have been placed into quarantine by health officials, in an effort to contain the virus.
South Korean authorities will also track the cellphones of more than 2,300 people under quarantine to prevent the spread of MERS.
Symptoms of MERS vary from fever, cough, diarrhea and loss of breath. The virus generally develops in less than two weeks. MERS spreads when in close contact with a carrier of the virus either from a human or animal. In the Middle East, Saudi Arabia, where the virus was first diagnosed in 2012, the cause was linked with human contact with infected camels.
Seventeen of the reported cases come from a single hospital in Seoul, which also serves as the first hospital to file a MERS case in South Korea
The disease is believed to have spread from an individual travelling from the Middle East to South Korea, according to the World Health Organisation (WHO). The 68-year-old man arrived in a Seoul hospital for treatment but was not isolated immediately because MERS was not suspected by Medical doctors, according to the WHO.
All confirmed cases of MERS have been in healthcare facilities, authorities said.
Health officials and medical staff have been criticised for their handling of the outbreak.
Seoul Mayor Park Won-soon has blamed the central government for providing inadequate information about the virus to South Korean citizens.
South Korean residents have expressed their concern over the rapid spread of the virus.
“MERS is dangerous. I think if I don't take precautions, I can contract the disease, so I wear this mask for prevention," Kim Sung-taek said to Associated Press.
"In order to take off this mask soon, I think the South Korean government should focus more on this problem [MERS] and act proactively," he added
Health Minister Moon Hyung-pyo denied such accusations as truth, saying these types of comments risked increasing public concern.
MERS has a death rate for the diagnosed at 27 percent, says the World Health Organisation.