Such confusion, often coupled with acrimony and threats of reprisals from countries who feel unfairly added to so-called "red lists" of Covid-19 unsafe destinations, looks set to undermine efforts to salvage Europe's vital summer tourism economy well before the warm sunshine months have cooled into winter.
The latest casualty is Croatia, which on Thursday was removed from the UK's safe list, meaning that anyone arriving in the UK from that country will be subject to a mandatory 14-day quarantine from Saturday at 0400 GMT.
The move, a response to resurgence of Covid-19 cases now affecting many European countries, will potentially block tens of thousands of British tourists from enjoying the sparkling blue waters and pretty islands of the Dalmatian coast, and deprive Croatia of what is usually its sixth highest source of visitors.
Earlier this week Croatia was red-listed, by Slovenia, its second largest tourist nationality, and Austria.
This comes as Belgium adds Malta to its higher risk list, along with Denmark, Finland, Lithuania, Bulgaria and the UK. Norway has added a number of destinations including Greece, Ireland, and Austria.
France was last week added to the UK's unsafe list, prompting yowls of protest both from the legions of British vacationers who see sojourning in their neighbor as an annual rite of summer, but also from French authorities who threatened reciprocal quarantine measure on arrivals from the UK.
As a result, many holidaymakers traveling between Europe's once wide-open internal borders must now decide whether to postpone, cancel, or go ahead with their trips and resign themselves to two weeks of self-isolating on their return.
Meanwhile destinations buoyed by a resurgence of tourists now find themselves back at square one.
It's a far cry from the excitement the news the European Union was throwing open its doors in July brought about.
A list of "safe" destinations from outside the bloc was soon drawn up, while various countries began opening up their borders to each other, such as the UK, which arranged "travel corridors" between England, Wales and Northern Ireland and destinations including Spain, Germany and France.