The army vehicles disinfect the road in Daegu, about 300 km southeast of the capital Seoul, South Korea, Feb. 29, 2020. (NEWSIS/Handout via Xinhua)

Containment of COVID-19 is feasible and "must remain the top priority for all countries," the WHO chief reiterated. "With early, aggressive measures, countries can stop transmission and save lives."

GENEVA, March 2  -- The head of the World Health Organization (WHO) said on Monday that the spread of COVID-19 in South Korea, Italy, Iran and Japan has become the greatest concern.

South Korea has so far reported more than 4,200 cases and 22 deaths, meaning it has more than half of all cases outside China, WHO Director-General Tedros Adhanom Ghebreyesus said at a daily briefing.