The UK, US, Japan and several other countries are working to fly their citizens out of Wuhan, the epicenter of the novel coronavirus outbreak in Hubei province.
The state department says travelers now in China should consider leaving the country "using commercial means" and has requested that "all non-essential USA government personnel defer travel to China".
The White House has said it is considering further restrictions on US airlines flying to China, in addition to the voluntary restrictions implemented by some air carriers.
China has reported 9,692 confirmed cases with a death toll of 213 as of Friday, and the World Health Organization has declared the outbreak a global emergency. A total of 98 cases have been confirmed in 18 other countries, but no deaths outside of China have been recorded, according to the WHO.
A charter flight carrying 367 South Koreans from Wuhan, the epicentre of a virus outbreak in China, landed at the Gimpo International Airport on Friday, South Korea's foreign ministry said.
Pakistan has yet to register a case, but top health official Zafar Mirza said four Pakistani students in China had been diagnosed with the new virus. British Airways has already suspended all flights to and from mainland China.
Zhang emphasized that the director-general said the main reason for the declaration is "not because of what is happening in China, but because of what is happening in other countries".
Officials say the student is not exhibiting any symptoms of the coronavirus, but they are responding proactively to the situation.
IL health officials are now investigating 21 other possible cases in the state. He added that Chinese President Xi Jinping had committed to help stop the spread of the virus beyond its borders.
China's U.N. Ambassador Zhang Jun said Thursday evening in NY that "we are still at a very critical stage in fighting the coronavirus" but stressed that the epidemic is still mainly confined to China and urged the worldwide community against any overreaction.
Experts say there is evidence of people-to-people transmission of the virus. So far, 31 of China's 33 provinces or administrative regions have reported cases.
The news comes after the US Centers for Disease Control and Prevention announced on Thursday that the husband of an IL woman with Wuhan coronavirus is now infected with the illness - the first confirmed case of person-to-person transmission in the United States. The two countries begin to screen anyone arriving from Wuhan. The woman had shown no symptoms of the virus until her flight back to China. 2019-nCoV as it is called, belongs to the coronavirus family, which includes SARS (severe acute respiratory syndrome) and MERS (Middle East respiratory syndrome), and spreads via airborne droplets.