I happen to watch a few channels about history. I haven't read the 536 piece yet but on one of the vids I watched, a body of an african american was accidentally unearthed in a iron coffin. At first, they thought it was a recent murder because the body was so well preserved. But then the iron pieces the excavator had mangled was found to be a coffin. When the archaeologists got there they were at first excited, then they were horrified. The body was covered with small pox pustules and they quickly called The Center of Disease and quarantined it in case there was still active viruses.
The small pox wasn't viable, but they showed pictures of what small pox did to people. It was terrible. I hadn't realized how awful it was because I thought chicken pox was similar to it. On the lady that had died 150 years ago, it was all over her body and they even found that was on the lining of her brain. Very painful way to die. So a vaccine was made and by 1980 -83 it was eradicated. But many had died and suffered from it.
The witness at work refuses vaccinations and I pointed out to her, she probably would have died if she hadn't taken it back then. In fact if no one took vaccinations, small pox would still be around. I remember taking the sugar cube for polio when I was a kid.
So many terrible diseases are cured or controlled today.
And of course, watching the history channels shows that humans can be cruel and vicious at any age in our history.