Expressing increasing alarm about mounting infections, the World Health Organization (WHO) declared Wednesday that the global coronavirus crisis is now a pandemic.

Tedros Adhanom Ghebreyesus, who heads the U.N. agency, said the WHO is “deeply concerned by the alarming levels of spread and severity” of the outbreak. He also expressed concern about “the alarming levels of inaction.”

“We have, therefore, made the assessment that COVID-19 can be charac-terized as a pandemic,” he said at a briefing in Geneva.

“All countries can still change the course of this pandemic. If countries detect, test, treat, isolate, trace and mobilize their people in the response,” Tedros said.