Authorities in charge of a hospital in the South Korean capital, Seoul, are offering apologies and changing strategies amid the current outbreak of MERS.

It's been revealed a staff member at the Samsung Medical Center continued to work at the hospital for days after being identified as a person who had potentially come into contact with the virus.

He's believed to have come into contact with around 200 people during the time he was still working.

Samsung Medical Center President Song Jae-hoon has issued a public apology.

He says they're now taking steps to cope with the spread of MERS at the facility.

"We will partially close the hospital in order to fully focus on counteracting MERS. Other than emergency operations, we are also going to temporarily set a restriction on out-patient treatments, hospitalisation, as well as operations and treatments on emergency patients. Also, we will limit the visitors coming in to visit in-patients."

Close to half of all the 145 confirmed cases of Middle East Respiratory Syndrome in South Korea can be traced to the Samsung hospital.

South Korean authorities have already sealed off two additional hospitals.

Around 4-thousand people in the country are now being quarantined.

The MERS virus has led to the deaths of 15 people since it was first identified in the country on May 20th.

However, the World Health Organization says it doesn't believe the spread of the virus will become a pandemic, as it has so far been confined to hospitals.

The WHO says it believes a combination of over-crowded emergency rooms, and so-called "doctor shopping, or people visiting different medical facilities to treat the same ailment, are the main factors behind the spread of the virus in hospitals.

It is recommending the South Korean government ban anyone from travelling overseas who may have been exposed to MERS.

A 38-year old South Korean national is currently being tested for MERS in Slovakia where he's employed at a factory run by South Korean car-maker Kia.