There are so many ways. They can be found in the food you eat, the water you drink, the air you breathe, from not washing your hands after you go to the bathroom, body fluids of all types including saliva, restaurant food, etc. more.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.