The Toronto house fly is the most common type of fly. Rubbish, manure and left-over food attract them. They are particularly common where animals are kept, attracted by animal food and excrement. Any organic matter left in a warm environment is likely to attract flies. The house fly prepares its meal by spitting saliva on to food. The saliva liquefies it, so the fly can then suck it up. This process can spread bacteria and viruses from rotting dead creatures and manure, to food about to be eaten by humans. Clearly, it is important to prevent Toronto flies from contaminating food, cooking equipment, plates and cutlery. It’s normal for a few flies to exist in any location, but a large number of them indicate a problem which needs to be identified and rectified. There may be a sewage leakage, or a dead creature providing food for the flies. Any such opportunity to lay eggs will attract flies. The eggs hatch out as maggots. These eventually become chrysalises which, in turn, produce flies in large numbers. Removing the source of food will reduce the opportunity for flies to breed, also reducing the number of flies to be dealt with in other ways. Most types of food consumed by humans attract flies. Try to prevent them gaining access to the food by covering it at all times, and by storing food in closely covered containers, or in the refrigerator or freezer. Always clean traces of food from surfaces used for food preparation, and put food waste into a lidded bin, to keep the flies out. It’s not easy to keep flies out of your home on a warm day, when you want the windows open. Various types of fly screens may be effective. The types with multiple strips of plastic or strings of beads help to deter flies from entering doorways – although they can be irritating when they get in your way on entering. Once flies have got into the home, it will be necessary to kill them or get them out of the home. Fly papers and traps – which include bait and a sticky surface – can provide effective fly control, reducing the number of flies quickly. Not everyone likes the idea of using insecticide in the home, but fly-killing sprays can be used by following the safety instructions carefully. You may prefer ultra-violet light traps, which attract and kill flies when they land on an electrified grid. UV traps and other types of fly control equipment are advertised for sale on appropriate websites. An irritating fly that defies capture or swatting can often be enticed out of the house at night by using the fact that flies tend to be attracted by bright light. Turn off the lights where the fly is being a nuisance and open the door to a lobby or hallway where the light should be left on. The fly should fly from the darkened room into the brightly lit area. Once trapped in this confined area, either swat it or open the door to the outside of the house and turn off the lobby light. The fly will normally fly out – particularly if you have an outside light on to attract it.