China says it has nearly 10,000 confirmed cases of the novel coronavirus. The virus has caused 213 deaths in China where it emerged late last year.
The World Health Organization says the worldwide spread of the virus is a global health emergency, as well as an "extraordinary event" requiring a coordinated international response.
The Trump administration is warning Americans not to travel to China.
The State Department issued what it calls a Level 4-Do Not Travel advisory. It also is recommending all those currently in China to leave.
The Centers for Disease Control and Prevention issued Tuesday a Level 3 notice, advising Americans to avoid all nonessential travel to China.
Britain reported its first confirmed cases Friday. "We can confirm that two patients in England, who are members of the same family, have tested positive for coronavirus," said Chris Whitty, chief medical officer for England. He said the two are receiving "specialist" care from the country's National Health Service.
India and Philippines have also confirmed their first cases, joining a growing list that includes Australia, Canada, Finland, Germany, Hong Kong, Japan, Nepal, Singapore, South Korea, Thailand, The United Arab Emirates and Vietnam.
According to a BBC report, the infection is difficult to spot and stop because only an estimated one in five cases will result in "severe symptoms" which means people can spread the infection without having any symptoms or without knowing they have the infection.
Dr. Nancy Messonnier of the Centers for Disease Control said they symptoms of a cold or the flu and the coronavirus are the same, but the risk factors are having visited China's Hubei province or having close contact with those who have been there.
The virus emerged in Wuhan in Hubei province. Wuhan is the epicenter of the outbreak and it has been shuttered. People have been instructed to stay home and public transportation has been shut down.
Mi Feng, China's National Health commission spokesperson said Friday, "The Chinese government has attached great importance to the epidemic control and we have already adopted the most stringent control measures . . . We hope to cooperate with other countries to safeguard regional and global health and public safety."