US President Donald Trump has called the guidelines of the Centers for Disease Control (CDC) "very impractical" and too restrictive, claiming that European schools are "open with no problems," NBC News reports.

He cited Germany, Denmark, Norway, and Sweden "along with many other countries" as places where schools were not being asked to adhere to such "impractical" guidelines, with no adverse results.

Officials and school administrators in all the countries cited were quick to respond, pointing out the key differences between the prevailing conditions in their country as opposed to in the United States, and noting that the US had locked down late and opened up early, unlike the policies followed by most European countries, excepting Sweden.