Earlier this week, the Centers for Disease Control (CDC) added three new countries to its travel advice in the wake of growing omicron cases. The Level 4 warning indicates a “very high” transfer rate with 500 COVID-19 cases per 100,000 people.

Sweden, Malta and Moldova joined the CDC’s list to avoid travel, med The US State Department issues a similar warning for all three countries and add Suriname as well. According to data from Johns Hopkins UniversitySweden, which has a population of approximately 10 million, has reported 95,712 new cases of covid in the past month. The United States has seen 4.9 million over the same period.

“If you have to travel to Sweden, make sure you are fully vaccinated,” the CDC said in its advice. “Due to the current situation in Sweden, even fully vaccinated travelers may be at risk of receiving and spreading covid-19 variants.”

For its own part, Sweden banned unnecessary travel from most countries outside the EU or EEA until 31 January as a precautionary measure. However, there are exceptions, including vaccinated US travelers with evidence of a negative covid test taken within 48 hours of departure.

At the time of writing, there are almost 90 countries CDC Level 4 List, including France, Germany, Iceland, the United Kingdom, Switzerland and Spain.

If you are planning to travel internationally, especially to one of the CDC’s Level 4 destinations, read on current eligibility requirements and that the Agency’s updated recommendations.