With a surge in the number of cases to 87 from 44 the previous day, South Korea has the second highest number of infections after Saudi Arabia, according to data from the European Centre for Disease Prevention and Control.
An 80-year-old man became South Korea's sixth fatality of a disease that first appeared in the Middle East in 2012.
Most of the disease's approximately 445 fatalities have been in the Middle East but memories are fresh in Asia of Severe Acute Respiratory Syndrome (SARS), which emerged in 2002-2003 and killed about 800 people worldwide.