Portugal has re-entered the maximum risk listIt is now a destination to avoid on any trip, having already been in this category in July of this year..

Thus, the U.S. government advises against any travel, which are most European countries, with exceptions for Finland, Italy, Malta, Spain and Sweden which remain at CDC risk level three.

"Due to the current situation in Portugal, even fully vaccinated travelers may be at risk of contracting or spreading Covid variants," the CDC website indicates, after stressing that "you should avoid traveling to Portugal" or ensure you have a full vaccination.

According to Monday's update, the maximum risk list now has 83 destinations, including, in addition to Portugal, France, Andorra, Cyprus, Liechtenstein, Tanzania, and Jordan.

However, for travel to the US, the center warns that before boarding everyone must have a negative test done at least 24 hours ago. "Only children under the age of two do not need to submit a test," reads the CDC document.

For now, the authorities also recommend that a new test be performed three to five days after arrival in the U.S.