I don't want NPCs to get killed by Vampire Attacks. How do I do this?
Solution 1:
I found the 'When Vampires Attack' mod which should help people with similar issues.
Solution 2:
If you don't want to mod your game, you can set individual NPCs essential using
setessential <baseid> 1
More info on using that command can be found here: In Skyrim, the console command to set a follower as essential is not working. What am I doing wrong?
Personally, I would go with the mod iber provided. It's not a 100% guarantee that NPCs won't die, but it drastically improves their survival rate, and you don't have to walk around town applying essential commands to every NPC.