The World Health Organisation (WHO) said on Sunday it appeared likely that the novel coronavirus, which has killed 18 people in the Middle East and Europe, could be passed between people in close contact.
The coronavirus is from the same viral family that triggered the outbreak of Severe Acute Respiratory Syndrome (SARS) that swept the world after starting in Asia in late 2003 and killed 775 people.
WHO Assistant Director-General Keiji Fukuda, speaking after a visit to Saudi Arabia
, the site of the largest cluster of infections, told reporters in Riyadh there was no evidence so far that the virus was able to sustain "generalized transmission in communities."
But he added: "Of most concern ... is the fact that the different clusters seen in multiple countries ... increasingly support the hypothesis that when there is close contact, this novel coronavirus can transmit from person to person."
A public health expert, who declined to be identified due to the sensitivity of the matter, said "close contact" in this context meant being in the same small, enclosed space with an infected person for a prolonged period of time.