All travelers from the U.S. will be tested for coronavirus on arrival at Incheon International Airport from Friday if they show symptoms. Those without symptoms will have to quarantine themselves for two weeks and must install a self-diagnosis app on their phones. Health authorities said they may consider testing all arrivals from the U.S. later if the situation gets worse.

Some 2,400 travelers arrived from the U.S. on average a day for the last three days. But resources are already overstretched and the government has downscaled entry screening for travelers from Europe because airport facilities could not cope.

Asked why it is taking different approaches to travelers from the U.S. and Europe, the government cited "different levels of epidemic risks" in the two regions.

"We took the latest measure because the tally of coronavirus cases continues to spike in the U.S. and an increasing number of arrivals from the U.S. have tested positive," a spokesman said Wednesday.

