Flies can’t chew their food so in order to eat, they secrete enzymes onto your food to dissolve it and make it digestible. This sounds really bad and it is, but it’s not the whole story.
The bacteria and viruses from their favorite foodstuffs get stuck to their body and can spread disease and makes people sick, not their enzymatic spit-up. The 3-second rule doesn’t apply to flies. They only need to touch your food for a second for their legs or the tiny hairs all over their bodies to transfer germs -- from all those nasty things they eat -- onto your lunch. And since flies can transfer serious, contagious diseases like cholera, dysentery, and typhoid, it's best if you try to avoid flies at all cost.
1) Keep screens repaired and unscreened doors and windows closed.
2) Clean up spills when they happen.
3) For one annoying fly in the house, a good old fly swatter is best!
4) At picnics or barbeques, keep foods covered when not serving.
5) A fan on a deck or patio will discourage flies from landing on food.
If you need help with a serious fly population, call 800-650-PEST!
Want to know more? Check out this video.