As the world moves unsteadily toward eliminating the threat of COVID-19, navigating the world can seem like moving across a map on which all the countries are different colors. The pandemic has been global, but the response to it is highly fragmented. There is no standard international code for how to create a safe environment while COVID continues to be present. Every country is going about it in its own way.

That’s great for the spirit of independence, but it creates a whole lot of annoying complications for travelers who, a couple of years ago, used to cross many international borders with ease. For Dan Austin, president of Austin Adventures, an operator of tour programs on several continents, it has become like an endless series of…