A 61-year-old man has died from pneumonia in the central Chinese city of Wuhan in an outbreak of a yet-to-be-identified virus, while seven others are in critical condition, local health authorities said on January 11.

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.

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 World Health Organisation (WHO) said 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.

When was the case first reported?

The man, the first victim of the outbreak that began in December, was a regular buyer at the seafood market, who had been previously diagnosed with abdominal tumours and chronic liver disease, the health authority said. Treatments did not improve his symptoms after he was admitted to hospital and he died on January 9 when his heart failed.

The commission added that no new cases had been detected since January 3. The Wuhan health authority also said that the patients were mainly vendors and purchasers at a seafood market in the city, and that to date no medical staff had been infected, nor had clear evidence of human-to-human transmission been found.

What is coronavirus?

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.

Globally, novel coronaviruses emerge periodically in different areas, including SARS in 2002 and MERS in 2012. Several known coronaviruses are circulating in animals that have not yet infected humans. As surveillance improves, more coronaviruses are likely to be identified.

What are the measures taken in China?

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

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 had completed nucleic acid tests.

Hong Kong’s department of health said in a separate statement 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.

The WHO said China has strong public health capacities and resources to respond and manage respiratory disease outbreaks. In addition to treating the patients in care and isolating new cases as they may be identified, public health officials remain focused on continued contact tracing, conducting environmental assessments at the seafood market, and investigations to identify the pathogen causing the outbreak.

SARS outbreak in 2003

SARS is a viral respiratory illness caused by a  coronavirus, called SARS-associated coronavirus (SARS-CoV). The disease was first reported in November 2002 in the Guangdong province of southern China. According to the WHO, a total of 8,098 people worldwide became sick with SARS during the 2003 outbreak. Of these, 774 died.

The main symptoms of SARS are high fever, dry cough, shortness of breath or breathing difficulties. Changes in chest X-rays indicative of pneumonia also occur. Based on currently available evidence, close contact with an infected person is needed for the infective agent to spread from one person to another.

MERS identified in 2012

MERS is a viral respiratory illness caused by a coronavirus (Middle East Respiratory Syndrome Coronavirus, or MERS‐CoV) that was first identified in Saudi Arabia in 2012.

A typical case of MERS includes fever, cough, and / or shortness of breath. Pneumonia is common, however some people infected with the MERS virus have been reported to be asymptomatic. Gastrointestinal symptoms, including diarrhoea, have also been reported.

The mortality rate for people with the MERS virus is approximately 35 per cent - this may be an overestimate, as mild cases may be missed by existing surveillance systems.

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