(Updates with detail on death toll, economist quote; adds detail on plasma infusions, financial market and economic impact)
* China says mainland cases rise by 5,090, 121 new deaths
* Japan reports first death, third outside mainland China
* Trump lauds China's response, top adviser more critical
* Graphic: https://tmsnrt.rs/3aIRuz7
By Yilei Sun and Prak Chan Thul
BEIJING/SIHANOUKVILLE, Cambodia, Feb 14 (Reuters) - China's coronavirus outbreak showed no sign of peaking with health authorities on Friday reporting more than 5,000 new cases, while passengers on a cruise ship blocked from five countries due to virus fears finally disembarked in Cambodia.
Policymakers pledged to do more to stimulate Asian economies hit hard by the virus, helping Asia stock markets edge higher, with Chinese shares headed for their first weekly gain in four.
In its latest update, China's National Health Commission said it had recorded 121 new deaths and 5,090 new coronavirus cases on the mainland on Feb. 13, taking the accumulated total infected to 63,851 people.
Some 55,748 people are currently undergoing treatment, while 1,380 people have died of the flu-like virus that emerged in Hubei province's capital, Wuhan, in December. The latest toll takes account of some deaths that had been double counted in Hubei, the health commission said.
The new figures give no indication the outbreak is nearing a peak, said Adam Kamradt-Scott, an infectious diseases expert at the Centre for International Security Studies at the University of Sydney.
"Based on the current trend in confirmed cases, this appears to be a clear indication that while the Chinese authorities are doing their best to prevent the spread of the coronavirus, the fairly drastic measures they have implemented to date would appear to have been too little, too late," he said.
Chinese scientists are testing two antiviral drugs and preliminary results are weeks away.
The head of a hospital in Wuhan, a city under virtual lockdown to prevent the spread of the virus, told reporters on Thursday that plasma infusions from recovered patients had shown some encouraging preliminary results.
Japan confirmed its first coronavirus death on Thursday - a woman in her 80s living in Kanagawa prefecture near Tokyo. The death was the third outside mainland China, after two others in Hong Kong and the Philippines.
Japan is one of the worst affected of more than two dozen countries and territories outside mainland China that have seen hundreds of infections.
Japanese policymakers vowed to step up testing and containment efforts after the death and confirmation of new cases, including a doctor and a taxi driver.
CAMBODIA WELCOMES CRUISE PASSENGERS
A cruise liner quarantined off a Japanese port has more than 200 people confirmed with the disease. Authorities have said they will allow some elderly people to disembark on Friday.
Passengers on another cruise ship that spent two weeks at sea after being turned away by five countries over coronavirus fears started disembarking in Cambodia on Friday.
The MS Westerdam, carrying 1,455 passengers and 802 crew, docked in the Cambodian port town of Sihanoukville on Thursday. It had anchored offshore early in the morning to allow Cambodian officials to board and collect samples from passengers with any signs of ill health or flu-like symptoms.
Cambodian Prime Minister Hun Sen greeted the passengers with handshakes and bouquets of roses as they stepped off the ship and boarded a waiting bus.
"My wife and I gave him some chocolates as a show of our appreciation," Lou Poandel, a tourist from New Jersey, told Reuters after he disembarked and met the Cambodian leader.
Separately, Royal Caribbean Cruises Ltd said it had cancelled 18 cruises in Southeast Asia and joined larger rival Carnival Corp in warning that its full-year earnings would be hit by the coronavirus outbreak.
Global health authorities are still scrambling to find "patient zero" - a person who carried the disease into a company meeting in Singapore from which it spread to five other countries.
The rise in China's reported cases on Thursday reflected a decision by authorities there to reclassify a backlog of suspected cases by using patients' chest images, and did not necessarily indicate a wider epidemic, a World Health Organization official said on Thursday.
Economists are assessing the impact of the outbreak on the world's second-largest economy and scaling back their expectations for growth this year.
After the extended Lunar New Year holiday, many migrant workers may still be stuck in their hometowns, far from their factories. Analysts at Nomura estimated only about 21% had returned as of Thursday.
China's economy will grow at its slowest rate since the global financial crisis in the current quarter, according to a Reuters poll of economists who said the downturn will be short-lived if the outbreak is contained.
"China is already easing its monetary policy and providing more liquidity while more stimulus is likely. Factories are starting to reopen albeit with some delays," said Yukino Yamada, senior strategist at Daiwa Securities.
The duration of the disruption to international travel and trade is a key factor in some economists' predictions for a slowdown in global growth in the short term.
Japan, the world's third-largest economy, is bracing for a sharp slowdown and some analysts expect another contraction in the current quarter as the virus outbreak hurts exports, output and consumption.
(Reporting by Yilei Sun, Vincent Lee and David Stanway in Beijing; Prak Chan Thul in Sihanoukville; Hideyuki Sano in Tokyo; Colin Packham and Paulina Duran in Sydney; Uday Sampath in Bengaluru; Writing by Lincoln Feast; Editing by Stephen Coates)
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