The Centers for Disease Control and Prevention is warning travelers about going to two more popular destinations – Jamaica in the Caribbean and Sri Lanka in South Asia – adding them both as “Level 4: COVID-19 Very High” risk travel locations as coronavirus cases surge.

The two tropical islands rank as the highest-risk destinations for travelers along with other locations such as Brazil, the Bahamas, Costa Rica, France, Greece, Iceland, Ireland, Malaysia, Portugal, South Africa, Spain, Thailand, Turkey and the U.K.

The CDC updated its travel advisory to include both Jamaica and Sri Lanka on Tuesday, saying that anyone who travels to the islands should be fully vaccinated against COVID first.

Jamaica has seen a low rate of vaccination across the island, with only 19 doses of the vaccine administered per 100 people as of Tuesday, according to CNN. The country has also issued a range of curfews since late August in an attempt to reduce the spread of the virus.

Sri Lanka has administered 102 doses of the vaccine per 100 people as of Tuesday but has seen cases of the virus surge in the region, CNN said.

The agency also added Brunei to the level 4 risk travel category on Tuesday.

The CDC recommends all international travelers be fully vaccinated, saying, “Fully vaccinated travelers are less likely to get and spread COVID-19. However, international travel poses additional risks, and even fully vaccinated travelers might be at increased risk for getting and possibly spreading some COVID-19 variants.”

The CDC raises the alert if there is a significant increase in COVID cases reported or a location’s case count meets or exceeds the threshold for a higher level for 14 straight days. For level 4, the location would need to have more than 500 new cases per 100,000 people over the last 28 days or more than 500 cases total if their population is less than 100,000.

A statue of Bob Marley, who helped transform reggae into a global phenomenon, in Kingston, Jamaica
A statue of Bob Marley, who helped transform reggae into a global phenomenon, in Kingston, Jamaica AFP / Mladen ANTONOV