Fox News Flash top headlines are here. Check out what's clicking on Foxnews.com. The Centers for Disease Control and Prevention (CDC) and the U.S. State Department on Monday issued their highest warnings against travel to the United Kingdom due to a rise in COVID-19 cases. They each raised their travel advisories to "level 4," telling Americans they should avoid travel there. "The Centers for Disease Control and Prevention (CDC) has issued a Level 4 Travel Health Notice for the United Kingdom due to COVID-19, indicating a very high level of COVID-19 in the country," the State Department said in its advisory.