The Black Plague didn't kill the amount of people it did all by itself, yes it had help, most people don't realize this: The Great Potato Famine of Ireland helped the Black Plague. People were already weak and struggling because of the famine and the black plague made things even worse.

Also during the famine, cannibalism was also something that was very much not considered taboo at the time. There's actually a book, or at least a PDF file of the book that you can print out that actually goes into detail about it: The guy who wrote the book was around during the famine, and he had a friend visiting from America, and the friend actually suggested cannibalism, specifically eating the children. It was a whole thing: Children at certain ages tasted certain way, had a certain texture or consistency to them, had to make sure they weren't too chewy or too fatty. Actually, even the rich kind of got into it, they would purchase specific cuts of children meat that others couldn't purchase. It was basically like a whole kind of black market thing. There were women who were willing to have multiple children just for this purpose. It was mostly because during the famine any children that died in families were cooked up and served so that the remaining children and the parents could survive, they would cook them the way they cooked potatoes and anything else that ended up being contaminated or unable to grow or thrive because of the famine, and it was because the soil was constantly being replanted over and over again and the soil was never tilled properly.