The Trump administration is holding off on blocking travel from Italy or South Korea, where two of the world's major coronavirus outbreaks are occurring, and has instead implemented heightened medical screening protocols for people flying from those countries to the United States.

"Part of the reason we're still flying is because those governments have been so aggressive in accommodating the medical requirements of having a successful screening system set up," Ken Cuccinelli, who is performing the duties of deputy secretary of homeland security, told reporters on Capitol Hill on Thursday. "So, that is great cooperation we get with both Italy and Korea that, you know, we were just not as close to China as we are to these two countries."

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Late Wednesday night, the DHS Transportation Security Administration required airlines operating flights from those two countries to the U.S. to carry out a more in-depth medical screening, as recommended by the Centers for Disease Control and Prevention, than solely taking people's temperatures prior to boarding.

The White House announced on Jan. 31 it would block non-U.S. citizens from entering the country if they had visited China within 14 days. On Feb. 29, it expanded the ban to include Iran, which has reported a couple thousand coronavirus cases. American citizens from China and Iran are allowed to return home but are directed to one of 11 U.S. airports for thorough medical screenings before being allowed in.

As of Wednesday, Italy reported more than 3,000 known cases, and South Korea on Thursday reported more than 6,000 cases. All four countries are under Level 3 travel alerts by the CDC, which is the highest level and urges people to avoid nonessential travel to those countries.

"This has never been, from Day One, intended to be a hermetically sealed process," Cuccinelli said. "We are trying to reduce and delay the biggest peak in the virus wave hit on the United States of America, and all of these steps reduce and delay. They do not stop the virus, and we've never suggested we were capable of that."

As of Thursday, the U.S. was shy of 200 cases nationwide, including cruise ship passengers who were repatriated from the Diamond Princess.