The WHO on Thursday declared the China coronavirus outbreak an international public health emergency, marking an escalation in the global response to an outbreak that has sickened more than 8,100 people and killed over 170 in that country, and led to growing spread of the virus through person-to-person transmission in the United States, Germany, Japan and Vietnam.

The designation gives the global health agency the ability to ramp up the responses of governments and organizations around the world as they try to control the outbreak.

In making the announcement in Geneva, WHO chief Tedros Adhanom Ghebreyesus said the decision was made to prevent the further spread of the virus to countries with weak health systems that are “ill-prepared to deal with it.”

“This decision is not a vote of no confidence in China,” he said, emphasizing the WHO “continues to have confidence in China’s capacity to control the outbreak.”

He praised China for the speed with which it identified the virus, sequenced its genome and shared it with the world, actions he called “impressive and beyond words.” There have been no deaths outside China, he said.

Tedros said the Chinese government should be congratulated for its “extraordinary measures” taken so far to control the outbreak, noting that the quarantines in place for about 50 million Chinese and other steps have already resulted in “severe social and economic impact” on the Chinese people.

“We would have seen many more cases outside China now and probably deaths if it was not for the progress they made to protect their own people and those of the world,” Tedros said.

Although the number of cases in other countries is relatively small, he said, the world must “act together to limit further spread.”

The WHO is urging countries to avoid measures that would limit trade and travel to China, he said.