The Big Spring Clean
Ba'al zebhul was a Canaanite god. His name literally meant lofty, superior Lord. The Hebrews pronounced the name of this god incorrectly - probably on purpose - as Ba'al zebhubh from ba'al 'lord' and zebhbh 'flies' making him the Lord of the Flies.
The Dutch then sarcastically called any time for cleaning, like a big spring clean, Beelzebub Feast. As the windows were opened after a long winter, the duvets aired, the rugs cleaned all little creatures that made their home in the house during winter were evicted.
Nowadays, the once lofty Lord Beelzebub has become the Lord of all Demons and is known as the devil himself. This is very fitting as it is his army of little mosquitos and the serious diseases and deadly viruses that they carry that pose one of the biggest threats to us humans.