Level 4: COVID-19 Very High category on the CDC's frequently updated list of risky destinations. The health agency recommends people avoid traveling to Level 4 locations, and if such travel is necessary, it cautions those doing so to be fully vaccinated beforehand.As of September 14, these are the destinations on the Level 4: COVID-19 Very High list in alphabetical order:The list is updated regularly, please check CDC's COVID notices before traveling.