I'm choosing not to link or display examples of imagery, since some of it can be triggering, and it's not like they're hard to come by online.
1. People in hospitals and morgues
The first month or two was people in China, then Europe (Spain and Italy), then America (New York City especially) either in hospitals or in morgues (often on the street). Also memorable were scenes of empty streets due to lockdowns and people on balconies.
2. Images of viruses
News stories would soon be adorned by a computer-generated image of a virus or a microbe.
3. Masks and people standing apart
As mask usage became more widespread, so did the images of people wearing them. This coincided with people posing standing apart ("social distancing") while still in frame. News stories of "social distancing" would often be accompanied by imagery of crowded beaches or parks (extremely few cases of COVID-19 would ultimately be traced to those gatherings). In Canada, we had a few laughs when hockey sticks were being used to put microphones in front of people. This coincided with imagery of anti-mask or anti-lockdown protesting. Videoconference calls became prevalent, so screenshots of gallery view found their way into news stories quite often.
5. Needles/syringes/people sitting in chairs, either in pharmacies or large venues, getting injected
As we entered the vaccine era starting December 2020, imagery shifted to needles in arms, and people sitting down and receiving the vaccine, or long lineups to receive it.
6. Shots of crowds at sports stadiums of masked and unmasked attendees and employees
Since May 2021, for me starting with the NBA, crowds at sports events seemed unreal. Now (September 2021), they seem a bit more commonplace, but there are still people who believe that everybody in the frame will die within two weeks of the event.
7. Photos of rapid tests either negative or positive, especially when those tests were hard to come by for individuals