resistance to this compound. This com-
pound is sometimes supplemented with a
pyrethrin-based nonresidual insecticide to
force the insects from the hidden areas to the
sprayed region, where improved contact with
the insecticide can occur. Other compounds,
such as flowable microencapsulated diazi-
non, are available for the control of cock-
roaches and other insects through spot,
crack, or crevice treatment, but not for
application in food handling areas. The liq-
uid pesticide, cyfluthrin, a parathyroid-class
chemical is as a nerve toxin that kills insects.
This chemical, which has a very low toxicity
to humans and pets, may be found in com-
mercial insecticides such as Raid. The pow-
der, disodium octoborate tetrahydrate, is a
boric acid formulation with low toxicity for
humans and pets, but causes insects to dehy-
drate and die (DeSorbo, 2004). Any com-
pound applied as an insecticide for the
control of cockroaches or other pests should
be used according to the directions on the
label.
Other Insects
The most common of the seasonal insects
in foodservice and food processing plants are
flies. The most populous varieties of flies
associated with these establishments are the
housefly and the fruit fly.
Thehousefly(Musca domestica), which is
found throughout the world, is an even
greater pest than the cockroach. It is a pest
to all segments of the community, transmit-
ting a variety of pathogenic organisms to
humans and their food. Examples are
human disease such as typhoid, dysentery,
infantile diarrhea, and streptococcal and
staphylococcal infections.
Flies transmit diseases primarily because
they feed on animal and human wastes and
collect these pathogenic microorganisms on
the feet, mouth, wings, and gut. These
pathogens are deposited when the fly crawls
on food or in the fly excrement. Because flies
must take nourishment in liquid form, they
secrete saliva on solid food and let the food
dissolve before consumption. Fly spittle, or
vomitus, is loaded with bacteria that con-
taminate food, equipment, supplies, and
utensils.
Control of flies can be a challenge because
these pests may enter a building that has
openings only slightly larger than the head of
a pin. Flies normally remain close to the area
where they emerged as adults, even though
they are lured to locations with odors and
decaying materials. Air currents frequently
carry flies a much greater distance than they
normally travel. Flies are most likely to
reside in warm locations protected from the
wind, such as electric wires and garbage can
rims. Houseflies lay an average of 120 eggs
within a week of mating and can produce
thousands of offspring during a single
breeding season. Warm, moist, decaying
material that is protected from the sunlight
provides an ideal environment for housefly
eggs to hatch, with subsequent growth of fly
larvae or maggots.
Houseflies are more abundant in the late
summer and fall because the population has
been building rapidly during the warm
weather. When adult flies enter buildings for
food and shelter, these pests generally
remain. Flies are most active in a 12 to 35ºC
environment. Below 6ºC they are inactive,
and below −5ºC death can occur within a few
hours. Heat paralysis sets in at approxi-
mately 40ºC, and death can occur at 49ºC.
It is difficult to control the size of a house-
fly population because they frequently breed
in areas away from food establishments
where decaying material exists. Therefore,
the most effective means of controlling the
fly population is to prevent them from enter-
ing processing, storage, preparation, and
serving areas and reducing their population
size within these areas.