GENEVA (REUTERS) - There has been "limited" human-to-human transmission of a new coronavirus that has struck in China, mainly small clusters in families, but there is potential for wider spread, the World Health Organisation (WHO) said on Tuesday (Jan 14).

A Chinese woman has been quarantined in Thailand with a mystery strain, authorities said on Monday, the first time it has been detected outside China.

In all, 41 cases of pneumonia - a symptom of the disease - have been reported in the central Chinese city of Wuhan, mainly through exposure at a seafood market.

Dr Maria Van Kerkhove, acting head of WHO's emerging diseases unit, told a Geneva news briefing that the agency had given guidance to hospitals worldwide about infection control in case of spread, including by a "super-spreading" event in a health care setting.

"From the information that we have it is possible that there is limited human-to-human transmission, potentially among families, but it is very clear right now that we have no sustained human-to-human transmission," she said.

The WHO is however preparing for the possibility that there could be a wider outbreak, she told a Geneva news briefing.

"It is still early days, we don’t have a clear clinical picture."

Some types of the virus cause less serious diseases, while others – like the one that causes Mers – are far more severe.

The UN agency has given guidance to hospitals worldwide about infection control in case the new virus spreads.

There is no specific treatment for the new virus, but anti-virals are being considered and could be "re-purposed", Dr Van Kerkhove said.

Preliminary lab tests cited by Chinese state media show that the virus could be from a new type of coronavirus.

Coronaviruses are a large family of viruses that can cause  Severe Acute Respiratory Syndrome (Sars).   Some of the virus types cause less serious disease, while some, like the one that causes the Middle East Respiratory Syndrome (Mers), are far more severe. 

The Wuhan Municipal Health Commission said on Monday that seven of the 41 had been discharged and six were in a serious condition.