South Korean President Park Geun-hye said on Wednesday everything must be done to stop Middle East Respiratory Syndrome (MERS) as fear of the disease shut hundreds of schools and led to corporate giant Samsung calling off a staff conference.

Five more cases were confirmed on Wednesday taking to 30 the number infected in South Korea since the outbreak began there two weeks ago. Two people have died, fuelling fear in the country with the most cases outside the Middle East, where the disease first appeared.

While there has been no sustained human-to-human transmission, the nightmare scenario is the virus changes and spreads rapidly, as Severe Acute Respiratory Syndrome (SARS) did in 2002-2003 killing about 800 people around the world.

MERS was first identified in humans in 2012 and is caused by a coronavirus from the same family as the one that triggered SARS. But MERS has a much higher death rate at 38 percent, according to World Health Organization (WHO) figures.

The WHO puts the total number of MERS cases globally at 1,161, with at least 436 related deaths, the vast majority in the Middle East. There is no cure or vaccine.

"There are a lot people worried about the situation," Park told an emergency meeting of ministers and top officials.

"Everything must be done to stop any further spread."

More than 200 schools were shut on Wednesday, most of them in the province of Gyeonggi, around Seoul, where the first death occurred on Monday.

South Korea has quarantined or isolated about 1,300 people for possible MERS infection.

A spokesman of Samsung Group [SAGR.UL], South Korea's top conglomerate, said an orientation conference for new staff scheduled for this week has been postponed in accordance with government instructions on public safety.

Media in the region has reported tourists cancelling visits to South Korea.

Though the WHO has not recommended trade or travel restrictions, South Korean border control authorities have put a ban on overseas travel for people isolated for possible infection, a health ministry official said.

China last week reported its first MERS case, that of a South Korean man who tested positive after breaking a voluntary house quarantine and traveling to Hong Kong and on to mainland China.

PRESSURE GROWING

South Korea reported its first two deaths from MERS on Tuesday.

Of the five new cases, four had been in the same hospital as the first patient, a 68-year-old man who had just returned from a trip to four countries in the Middle East. The other, a 60-year-old man, caught it from another infected person.

Media said health authorities were conducting tests on an elderly patient who died on Sunday after sharing the same hospital ward with one of the two MERS-infected people who had died. Officials said it was likely she died of existing illness.

The new cases would bring the total number globally to 1,166, based on World Health Organization (WHO) data, with at least 436 related deaths.

Pressure is growing for the government to identify the hospitals treating infected patients as fear and confusion mount.

Public health authorities have insisted it was "helpful" to keep the names of the hospitals from the public, but in an opinion poll published on Wednesday 83 percent of respondents demanded that the government identify them.

Ian Jones, a specialist virologist at Britain’s University of Reading who has followed MERS since it emerged, said transparency would help in the effort to stop the outbreak.

"Being open about the cases, their locations and their condition, is best for control - even if this causes some alarm in the short term," he said.

Some experts have said the 38 percent death rate from MERS might be overstated as patients with little or no symptoms might go undetected. The death rate from SARS was 9 to 12 percent, rising to more than 50 percent for patients over 65.

Symptoms of MERS can include cough, fever and shortness of breath. It can lead to respiratory failure, the WHO said.