Of course you know, fly swatters are no longer allowed, by law, in hospitals and resturants.
Fly swatters are kept out of sight in the ER where my husband works.
Fly swatters are hidden in our local resturant.
We live in ranch country, a plague of flies this year, and it’s revolting.

And generally when its a swarm like that, they bite. It really is miserable.
Us too. My barn has been infested with flies this year. I think we are finally starting to get it under control.
A rolled-up magazine works for me.
I noticed clear bags of water hanging from the eaves at this outdoor eatery in South Texas (New Braunfels), I was told they keep the flies away.
Looks like it works:
http://hardwareaisle.thisoldhouse.com/2008/06/bag-o-water-fri.html