Two people hospitalized in South Korea with Middle East Respiratory Syndrome (MERS) are being treated with an experimental blood plasma treatment, health officials announced on Tuesday.

As the death roll from the latest outbreak rose to 19, doctors said they were trialing a procedure which involves injecting patients with blood plasma from those who have recovered from the disease.

Health officials say they've carried out the treatment on two consenting MERS patients in additional to their existing care which includes quarantine and in severe cases, care to support the functioning of vital organs.

But doctors acknowledge that they there is insufficient evidence that the new treatment works as the virus continues to baffle experts.

Some success

The procedure was first tried during the outbreak of a similar illness, Severe Acute Respiratory Syndrome (SARS), with some success. It led to a 23 percent death rate from the SARS virus, which killed 774 people in 2002/3.

On Tuesday, South Korea reported three more fatalities from the largest outbreak of MERS outside of Saudi Arabia, where the virus was first diagnosed three years ago. The death toll has now reached 19.

Out of 154 people infected over the past month, 17 have been cured and released from hospital and health authorities said the number of new cases was falling, leading to hope that the worst was over.

Almost half of the confirmed cases have been traced to one of the most prestigious hospitals in Seoul. Another hospital in Pyeongtaek City, has also seen a large number of cases.

More than 5,500 people remain in quarantine after possibly being exposed to the virus.

The World Health Organization's MERS emergency committee was due to meet in Geneva on Tuesday amid fears MERS could spread to other countries as easily as SARS did a decade ago.

MERS death in Europe

Separately, Germany has reported its first death from MERS in more than two years.

The 65-year-old man was infected during a trip to the United Arab Emirates in February. He had been in hospital since his return and his death has surprised heath officials who thought he had almost recovered.

The only other case in Germany happened when a UAE national died in a Munich hospital in March 2013.

mm (AFP, dpa)