By Virginia Langmaid and Marnie Hunter, Aug. 6 (CNN): The US Centers for Disease Control and Prevention added 16 destinations to its "very high" Covid-19 risk level on Monday, including Greece, Ireland and the US Virgin Islands.

According to the CDC, a risk designation of "Level 4: Covid-19 Very High" means people should avoid travel to these locations. Those who must travel should be fully vaccinated first.

In its overarching guidance, the CDC recommends against all international travel until you are fully vaccinated.

"Fully vaccinated travellers are less likely to get and spread Covid-19. However, international travel poses additional risks, and even fully vaccinated travellers might be at increased risk for getting and possibly spreading some Covid-19 variants," the agency says.

Destinations that fall into the "very high" risk category have had more than 500 cases per 100,000 residents in the past 28 days, according to CDC parameters.

Direct travel of noncitizens from Ireland and Greece to the United States has been suspended since January 25, 2021, under an executive order limiting travel from multiple countries. The White House recently said those restrictions would remain in place amid surging cases from the Delta variant

The following 16 destinations moved to the CDC's "Level 4: Covid-19 Very High" category:

-- Andorra
-- Curaçao
-- Gibraltar
-- Greece
-- Guadeloupe
-- Iran
-- Ireland
-- Isle of Man
-- Kazakhstan
-- Lesotho
-- Libya
-- Malta
-- Martinique
-- Saint Barthelemy
-- Saint Martin
-- US Virgin Islands.

Here are some other typically popular travel destinations on the Level 4 category:

-- Brazil
-- Colombia
-- Costa Rica
-- Maldives
-- The Netherlands
-- Panama
-- Portugal
-- Seychelles
-- Spain
-- United Arab Emirates
-- United Kingdom