Have you kept with the different scientific developments through the years? Do you have a favorite invention/discovery/etc?
When I was a young mortal man I heard about the vaccine--inoculation, we called it--for smallpox. I never received it, of course, it was not yet widely available, but it was something being talked about in Paris. A few days of sickness, if that, and then you couldn't get smallpox? Might as well say that you waved a magic wand. Smallpox could take out entire families, it could kill in a matter of days, or linger for months. It was the bogeyman under the bed and the constant neighbor of life. And the idea that it could be just.... GONE? We didn't have much of an idea of "herd immunity" per se, but we did understand if no one got this disease it couldn't spread. By 1810 or so, the vaccine has reached New Orleans, and everyone was taking their children to get vaccinated. Claudia, of course, insisted. It was FASHIONABLE, you see, and she wanted to know if the needle hurt.
That was it for vaccines for a while. I slept through measles, mumps and rubella. I even slept through polio. But when I woke up and was talking to someone, must have been in the early 90s and she mentioned getting her son vaccinated I, rather stupidly said "for smallpox?" And she TOLD me that basically all diseases, all deadly plagues that maimed and killed and scarred were gone with punctures to the arm. And if you got some terrible disease, they gave you a pill made from mold and fungus and you GOT BETTER.
People didn't fear disease any more. Plagues didn't take out whole towns. Childhood wasn't touch and go. Children got chicken pox, maybe, and saw it as a break from school, tonsillitis as an excuse to eat nothing but ice cream. People went their whole lives not knowing someone who had died young and tragically from a sudden illness. Even yellow fever, that peril of New Orleans summers, the disease that killed Claudia's mother, was gone. GONE!
So yes, out of medical discoveries, those are my favorites.
Now, can you just get a nice vaccine for Coronavirus already? I miss seeing people on the streets. It brings back rather uncomfortable memories.