World Health Organization (WHO) chief Tedros Adhanom Ghebreyesus, however, advised against referring to a pandemic
Asia reported hundreds of new coronavirus cases on Wednesday, including a US soldier stationed in South Korea, as the United States warned of an inevitable pandemic and outbreaks in Italy and Iran spread to other countries.
The disease is believed to have originated in a market selling wildlife in the central Chinese city of Wuhan late last year and has infected about 80,000 people and killed more than 2,700, the vast majority in China.
The US Centers for Disease Control and Prevention urged Americans to prepare, saying that while the immediate risk there was low the global situation suggested a pandemic was likely.
"It's not a question of if. It's a question of when and how many people will be infected," the CDC's principal deputy director, Anne Schuchat, said on Tuesday.
World Health Organization (WHO) chief Tedros Adhanom Ghebreyesus, however, advised against referring to a pandemic.
"We should not be too eager to declare a pandemic without a careful and clear-minded analysis of the facts," Tedros said in remarks to Geneva-based diplomats.
The United States has reported 57 cases of the virus. US President Donald Trump, back in Washington after a visit to India, said on Twitter that he would meet US officials for a briefing on the coronavirus.
The WHO says the outbreak peaked in China around February 2, after authorities isolated Hubei province and imposed other containment measures.
South Korea, which with 1,261 cases has the most outside China, reported 284 new ones including a US soldier, as authorities readied an ambitious plan to test more than 200,000 members of a church at the centre of the outbreak.
The US military said a 23-year-old soldier based in Camp Carroll, about 20km from Daegu, had been infected and was in self-quarantine at home.
The first case of the coronavirus has been confirmed in South America as health authorities in Brazil announced on Wednesday that a man had been diagnosed with COVID-19 in Sao Paulo, meaning that the deadly infection has now reached every continent besides Antarctica.
In Japan, Prime Minister Shinzo Abe called for sports and cultural events to be scrapped or curtailed for two weeks to stem the virus as concern mounted for the 2020 Tokyo Olympics.
Japan's professional baseball teams would play matches without spectators until March 15 due to virus concerns, Kyodo news agency reported.
Iran's deputy health minister - seen mopping his brow at a televised news conference - was among its 139 coronavirus infections. Cases linked to Iran have been reported across the region.
Kuwait said six new coronavirus cases, all linked to travel to Iran, took its tally to 18, while Bahrain said its infections had risen to 26 after three new ones on a flight from Iran.
Two hotels, one in Austria and one in Spain's Canary Islands, were also locked down after cases emerged linked to Italy. Spain also reported its first three cases on the mainland.