My wife and I have just returned from a Viking River Cruise starting in Budapest and ending in Passau, Germany with an extension to Prague.
We were a bit nervous with the resurge of the Delta phase about going but, ended up feeling more safe on the River cruise than if we stayed at home. Traveling requires a PCR test prior to boarding your flights overseas and luckily CVS got our test results to us a day before leaving. That was the hardest thing we had to do for the entire cruise.
We were tested daily (PCR saliva test) on the " river boat" along with everyone else and all the cruisers were diligent about their masks. When sitting in the common areas I noticed Viking staff continually disinfecting commonly used surfaces and spraying with steam. We thought to ourselves, these folks are truly serious about keeping us all safe. No problems, no sickness or breakouts during our time with Viking.
Great cabins with ample storage a balcony!