The 69-year-old man had been admitted to hospital with abnormal renal function and severe damage to multiple organs, the Wuhan municipal health commission announced. He died on 15 January.
At least 41 people have been diagnosed with pneumonia linked to the new virus, prompting authorities in Hong Kong to step up detection measures, including temperature checkpoints for inbound travellers.
Preliminary lab tests cited by state media showed the pathogen could be from a new type of coronavirus, a large family of viruses that can cause infections ranging from the common cold to deadly severe acute respiratory syndrome (Sars).
On Thursday Japan confirmed a man in his 30s had been infected with the virus, and a Chinese woman was quarantined in Thailand with a mystery strain of coronavirus. The World Health Organisation (Who) has warned a wider outbreak is possible.
The Wuhan health commission said late on Thursday that 12 people had recovered and been discharged from hospital but five others were in serious condition.
Two other cases have been detected – in Thailand and Japan – and health managers in both countries said the patients had visited Wuhan before being hospitalised.
Authorities in Wuhan said a seafood market was the centre of the outbreak. It was closed on 1 January.
The outbreak comes ahead of the lunar new year holiday in late January, when many of China’s 1.4 billion people travel to their home towns or abroad.
The Wuhan health commission also said no human-to-human transmission had been confirmed but the possibility “cannot be excluded”.
A Who doctor has said it would not be surprising if there was “some limited human-to-human transmission, especially among families who have close contact with one another”.
The woman diagnosed in Thailand had not reported visiting the seafood market, the Who said on Tuesday. She was reported to be in stable condition earlier this week.
The patient in Japan, who was released from hospital, had also not visited the market. Japanese officials said it was possible that he had been in contact with a person infected with the virus while in Wuhan.
The first confirmed fatality was a 61-year-old man in Wuhan who died of pneumonia after testing positive for the virus.
Memories remain fresh in Asia of a 2002-03 outbreak of Sars which emerged in China and killed nearly 800 people around the world.
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