New virus believed to cause China's mystery pneumonia outbreak

China believes a mysterious pneumonia outbreak that struck 59 people is caused by a new strain of virus from the same family as Sars, which killed hundreds of people more than a decade ago.

Lead scientist Xu Jianguo told the official Xinhua news agency that experts had "preliminarily determined" a new type of coronavirus was behind the outbreak, first confirmed on December 31 in Wuhan, a central Chinese city with a population of over 11 million.

It initially sparked fears of a resurgence of highly contagious Sudden Acute Respiratory Syndrome (Sars), and prompted authorities in Hong Kong –– badly hit by Sars in 2002-2003 –– to take precautions, including stepping up the disinfection of trains and aeroplanes, and checks of passengers.

China has since ruled out a fresh outbreak of Sars, which killed 349 people in mainland China and another 299 in Hong Kong.

"A total of 15 positive results of the new type of coronavirus had been detected" in the lab, through tests on infected blood samples and throat swabs, Xu said.

“It may take years for researchers to develop medicines and vaccines,” the Xinhua report said.

Dozens infected

The World Health Organization (WHO) confirmed the preliminary discovery of a new coronavirus in a statement.

As of Sunday, the Wuhan Municipal Health Commission said 59 people in the central Chinese city were being treated for the respiratory illness.

Seven were in critical condition, while the rest were stable.

Laboratory experts as of Wednesday evening had found the novel coronavirus in 15 of those cases, CCTV said, adding that more research must be done before a conclusion is reached.

What are coronaviruses?

Coronaviruses are a large family of viruses that was first identified in humans in the mid-1960s. 

Some are a cause of the common cold, while others found in bats, camels and other animals have evolved into more severe illnesses, such as Sars and Mers.

The family derives its name from the Latin word “corona,” meaning a halo or crown, which the viruses resemble when viewed under an electron microscope.

The WHO noted that coronaviruses emerge periodically - including in 2002 to cause Sars and in 2012 to cause Mers.

How do coronaviruses spread?

Coronaviruses can spread through coughing or sneezing, or by touching an infected person.

Common symptoms include a runny nose, headache, cough and fever. Shortness of breath, chills and body aches are associated with more dangerous kinds of coronavirus, according to the Center for Disease Control and Prevention.

The Wuhan Municipal Health Commission said some of the infected patients ran businesses in a seafood market that is being suspended and investigated. 

As the present illness does not transmit readily between people, it's possible they were infected by animals at the market.

The novel coronavirus is different from those that have previously been identified, CCTV said.

What happens next?

Chinese researchers made their preliminary determination by using an isolate from one positive patient sample to conduct gene sequencing of the virus, according to a statement from Gauden Galea, a WHO representative to China.

“Preliminary identification of a novel virus in a short period of time is a notable achievement,” Galea said.

But more must be done before scientists can reach a definitive conclusion. 

“More comprehensive information is required to confirm the pathogen, as well as to better understand the epidemiology of the outbreak, the clinical picture, the investigations to determine the source, modes of transmission, the extent of the infection, and the countermeasures implemented,” the WHO said.

Xu told Xinhua state news agency that they will conduct pathogenic and epidemiological research over the next several weeks to confirm that it is indeed a new coronavirus.

Heavy travel amid outbreak

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 aeroplanes, officials said during a briefing on Thursday.

Wang Yang, the Chinese transport ministry’s chief engineer, said at the briefing that authorities will step up efforts to prevent the pneumonia outbreak from spreading further during the holiday period, including ensuring proper disinfection in major public transportation hubs.

In 2003, Chinese officials covered up a SARS outbreak for weeks before a growing death toll and rumours 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.