This is England but we are infested with blowies - blow flies, blue bottles, those pesky things that buzz and fly and bump into things especially windows, and sometimes people. It started with one or two in the living room and daily their numbers grew. We used the tea-towel method of elimination and fed the carcasses out of the window into the garden for the birds. BUT, by today things were way out of control and I am afraid we had to resort to spray. Every piece of furniture, soft and otherwise has been moved and inspected. The garden bed had been poked at and foilage disturbed to see if any sort of bird or mammal had shuffled off its mortal coil beneath the window, but it seems not. The horrifying fact is that there is/was probably something INSIDE responsible for this population explosion.
The girls find it deeply embarrassing. I just am annoyed that they got the better of me...and I had to use spray.