Ok- all well and good. Now show any research showing fleas eating.... grain. Fleas require blood, as any animal owner knows when trying to get rid of them. The flea vector is still there in regards Bubonic Plague. In the Middle Ages, people obviously did not make the connection, and commonly the poor ate rats for subsistence. A cruel irony that the fleas off of their meal bit and killed them. 50% loss of population is really something.