Before The Professor gives his opinion of travel safety in regards to COVID and in the age of COVID, let's make a few things very clear.  First of all, The Traveling Professor is not a medical expert.   The Professor is not qualified to give any expert testimony on the safety of COVID and travel.   Other than the statistics cited, the following blog posts provides only non-professional and casual observations on the state of COVID and travel taken from personal experiences. 

The Traveling Professor recently completed two small group tours.  One was a small group tour (15 travelers plus The Professor) to Montreal and Quebec City Christmas Markets in early December of 2021.  The other trip was a trip to Northern Italy with a small group of travelers (about 12, plus our tour leader Micaela) in October of 2020.

The statistics that can be cited now, as of December 15, 2021, the source being Reuters: https://graphics.reuters.com/world-coronavirus-tracker-and-maps/

• United States: 261 infections per 100K people reported last 7 days.  74.1% of Americans are vaccinated. (according to Reuters on December 15, 2021).
• Canada:  79 infections per 100k people reported in the last 7 days.  84.6% of Canadians are vaccinated.  (according to Reuters on December 15, 2021).  
• Italy:  206 infections per 100K people reported last 7 days.  85.5% of Italians are vaccianted.  (according to Reuters on December 15, 2021).

Those are the statistics for the entire population.  But another thing that needs to be considered is the population that travelers will be in contact with while traveling:

• Travelers will be vaccinated.  A majority of them have 2 jabs.  Many have an additional booster jab. 
• In order to cross a border into Canada or Italy, travelers needed to test negative with a PCR test within 3 days of crossing into that country.
• Upon crossing a border, a traveler may be randomly selected for additional COVID testing.
• Pilots, flight attendants, and others interacting with travelers have vaccine requirements and are required to wear masks at times.
• Travelers may be required to wear masks indoors and while traveling on busses, trains, ferries, etc.
• In order to travel on trains, busses, enter restaurants, etc., most are required to submit proof of vaccination.
• Many of those who interact with travelers have vaccine requirements and may be required to practice COVID protocols like social distancing or wear masks.

So while traveling, one can make a judgement if they are interacting with people who are more protected against COVID infection than the general population. 

In the end, it is the traveler who needs to make the final decision on whether they feel comfortable or not to travel.