SHANGHAI (Reuters) - A 61-year-old man has died from pneumonia in the central Chinese city of Wuhan after an outbreak of a yet to be identified virus while seven others are in critical condition, the Wuhan health authorities said on Saturday.

In total, 41 people have been diagnosed with the pathogen, which preliminary lab tests cited by Chinese state media earlier this week pointed to a new type of coronavirus, the Wuhan Municipal Health Commission said in a statement on its website.

It said the pathogen was an “unknown cause of viral pneumonia”.

Two of them have been discharged from hospital and the rest are in stable condition, while 739 people deemed to have been in close contact with the patients have been cleared, it said.

The man, the first victim of the outbreak that began in December, was a regular buyer at a seafood market in the city, who had been previously diagnosed with abdominal tumors and chronic liver disease, the health authority said.

Treatments did not improve his symptoms after he was admitted to hospital and he died on the evening of Jan. 9 when his heart failed. He tested positive for the virus, it added.

The commission added that no new cases had been detected since Jan. 3.

The Wuhan health authority also said that the patients were mainly vendors and purchasers at the seafood market, and that to date no medical staff had been infected, nor had clear evidence of human-to-human transmission been found.

The World Health Organization (WHO) said on Thursday that a newly emerging member of the family of viruses that caused the deadly Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS) outbreaks, could be the cause of the present outbreak.

Coronaviruses are a large family of viruses that can cause infections ranging from the common cold to SARS. Some of the virus types cause less serious disease, while some like the one that causes MERS, are far more severe.

The outbreak comes ahead of the Lunar New Year holidays in late January, when many of China’s 1.4 billion people will be traveling to their home towns or abroad. The Chinese government expects passengers to make 440 million trips via rail and another 79 million trips via airplanes, officials told a news briefing on Thursday.

The Wuhan health authority in its statement also urged the public to take more precautions against infectious diseases, and said it was pushing ahead with tests to diagnose the pathogen and as of Friday had completed nucleic acid tests.

China’s National Health Commission said in a separate statement that it would share information on the genome sequence of the coronavirus with the WHO to safeguard global health security.

Hong Kong’s Department of Health also said on Saturday that it strengthened checks and cleaning measures at all border check points, including the port, airport and the city’s high-speed rail station which receives passengers from Wuhan city.

In 2003, Chinese officials covered up a SARS outbreak for weeks before a growing death toll and rumors forced the government to reveal the epidemic. The disease spread rapidly to other cities and countries. More than 8,000 people were infected and 775 died.