My belief is that the CDC, though well-intentioned, is kind of 'overcooking the goose' here with these latest advisories. For example, St. Barthelemy is also listed as Category 4 through there hasn't been a COVID-19 case on that island for over a week. So maybe the advisory is more to warn people about the hotel costs there which are averaging about $1,200 per night! Not only is St. Bart's expensive, but it is extremely safe so the Cat 4 rating would indicate there was very little research being done by the CDC regarding many of these destinations. Or, could this simply be an approach being used to keep tourism dollars in the states this year? But, in reality many of the countries on this list should fall somewhere between category 2 and 3. Another example is Spain, where cases have been very low for the past two months. Using a 'broad brush' approach by the CDC doesn't really work other than promulgating fear and that is never helpful. But, as Carol pointed out above if you are fully vaccinated you'll have little to worry about as long as you follow common sense protocols (such as mask wearing when inside at crowded environments). So, don't let this inhibit your plans to travel to St. Maarten this year.