Seeing a flea signifies a weak and poor person. Being bitten by a flea signifies wealth that will come into one's possession. Killing a flea signifies being safe from the harm of a treacherous, foul-tongued man.
Imam al-Nabulsi said: Fleas are the soldiers of Allah Most High.
Seeing fleas bite signifies grief and threats reaching the dreamer from ill-mannered people.