The U.S. Centers for Disease Control and Prevention (CDC) has added 22 countries and territories to its highest travel risk category, “Level Four: Very High,” due to the ongoing surge in COVID-19 cases from the omicron variant. Among the countries the CDC is telling American travelers to avoid are Israel, Australia, Panama, Bolivia, Qatar and Bermuda. Most of the popular destinations in the Caribbean were also added to the Level 4 category including:

• Aruba
• The Bahamas
• Barbados
• Belize
• British Virgin Islands
• Turks and Caicos
• Saint Lucia
• Sint Maarten
• Saint Kitts and Nevis
• Grenada

The CDC now has over 100 countries and territories at Level 4 as a result of the continuing surge caused by the omicron strain of the coronavirus, including popular European nations like the U.K., Italy and Spain. The agency typically assigns countries the Level 4 categorization when more than 500 positive cases per 100,000 residents are reported in the previous 28 days. According to the CDC website, if you have to travel to a Level 4 country, you should be fully vaccinated to protect yourself.

Another 20 countries were bumped to Level 3: High Risk. They include:

• Jamaica
• Costa Rica
• Cuba
• Hong Kong
• China
• Uganda
• Kuwait
• The Philippines

The CDC recommends that unvaccinated Americans avoid nonessential travel to destinations categorized as Level 3.

Related: The difference between the State Dept. and CDC travel warnings

The U.S. State Department also updated its own travel warnings this week, adding 25 countries to “Level 4: Do Not Travel,” its highest risk classification. The State Department’s advisories typically mirror those of the CDC, and most of the countries the CDC added to its highest-risk category also received a new warning.

But the State Dept. warnings take other factors into account when assessing the risk involved with traveling to a nation or territory. These factors include civil unrest, natural disasters, crime, terrorism, and currently, COVID-19. That is why Jamaica is at “Level 4: Do Not Travel” on the State Department’s advisory list, but it’s Level 3 for the CDC.

The State Dept. identifies risk factors in each country’s advisory with initials in the top right-hand corner that correspond to the chart below:

C=Crime
T=Terrorism
U=Civil unrest
H=Health risks, including COVID-19
N=Natural disaster
E =Time-limited event
O =Other potential risks not covered by previous risk indicators
K= Kidnapping/hostage-taking

The latest advisory for the Bahamas below includes a C for crime, and H for health risks.