There may have been limited human-to-human transmission of a new coronavirus in China within families, and it is possible there could be a wider outbreak, the World Health Organization (WHO) said on Tuesday.
Coronaviruses are a large family of viruses that can cause infections ranging from the common cold to SARS.
A Chinese woman has been quarantined in Thailand with a mystery strain of coronavirus, Thai authorities said on Monday, the first time the virus has been detected outside China.