The World Health Organization said Thursday the deadly virus that prompted the Chinese government to lock down nearly 20 million people in three cities has not developed into a worldwide health emergency.
"This is an emergency in China, but it has not yet become a global health emergency," WHO Director-General Tedros Adhanom Ghebreyesus said after a two-day emergency meeting in Geneva.
The U.N. health agency's decision came after it received details from independent experts who spent two days assessing information about the spread of the new coronavirus.
WHO considers an international emergency an "extraordinary event" that puts other countries at risk and one that requires a coordinated global response.
Map: Where has 2019 Novel Coronavirus Been Detected? New virus, denoted 2019-nCoV by the WHO, has caused alarm because of its similarity to SARS in 2002-2003
The Chinese government isolated three cities Thursday, an unprecedented move to contain the virus, which has spread to several other countries.
Authorities first banned planes and trains from leaving the city of Wuhan, where the coronavirus is believed to have originated. Toll roads were closed, and ferry, subway and bus services were also suspended.
Similar measures were taken hours later in the nearby cities of Huanggang and Ezhou.
The cities were put on lockdown on the eve of the Lunar New Year, when millions of Chinese traditionally travel. The government also canceled holiday events in Beijing that usually attract large crowds.
The virus has killed at least 17 people, all in and around Wuhan, and infected nearly 600 others.
Wuhan authorities have demanded that all residents wear masks in public and urged government and private sector employees to wear them in the workplace, according to the Xinhua news agency, which cited a government official.
China's efforts to contain the virus are apparently aimed at avoiding mistakes in its handling of the severe acute respiratory syndrome (SARS) outbreak that spread from China to more than a dozen countries in 2002-03 and killed about 800 people.
Even after SARS had spread worldwide, China housed patients in hotels and transported them in ambulances to hide the actual number of cases and to avoid WHO experts.
Fifteen medical workers are among those who have been infected by the new virus, which has spread from Wuhan to Beijing, Shanghai and Guangdong province, as well as Japan, South Korea, Thailand, Taiwan and the United States.
The U.S. announced its first case Tuesday in the northwestern state of Washington. Health officials there said a man who returned to Seattle from Wuhan last week was hospitalized in good condition with pneumonia.
U.S. President Donald Trump assured reporters during a press conference Wednesday in Davos, Switzerland, that U.S. officials "have a plan" to deal with the new outbreak, praising experts at the Centers for Disease Control and Prevention as "terrific, very great professionals, and we're in great shape."
Chinese health experts say they know little about the new strain, dubbed 2019-nCoV. They suspect the outbreak started in a Wuhan seafood market, which also sold other animals such as poultry, bats, marmots and wild game meat.
China's National Health Commission announced Monday the virus, which causes a type of pneumonia, can be transmitted person to person and not just from animals to people.
Airports around the world have begun screening travelers from Wuhan for the virus. Health experts are especially concerned about the chance of a pandemic as millions of Chinese citizens plan to travel across the country and overseas for the Lunar New Year holiday that starts Saturday.
A coronavirus is one of a large family of viruses that can cause illnesses ranging from the common cold to the deadly SARS.