I’ve read Anti-Judaism. It’s an important piece of work.

The point of the blood libel categorisation is that the Jew is personified as the embodiment of all evil specifically because he could kill Jesus. If he could kill Christ — the worst sin imaginable — he is capable of anything and everything else. Hence the accusation of poisoning the wells and the murder of children, these are two horrifying and horrific accusations but because the Jews were capable of killing Jesus then they are capable of these — and many other — monstrous acts.