Pest Control

 Pest Control

During the past century, an estimated 10 million people died from rodent-borne diseases An effective program against pests begins with a basic understanding of the characteristics of pest contamination sources and a comprehensive knowledge of safe and effective extermination and control procedures. If a pest control operator is not used to control pests, one or more employees should be trained and made responsiblefor maintaining effective pest control.

INSECT INFESTATION

COCKROACHES

The most common pests among food processing plants and foodservice facilities throughout the world are the cockroaches. Control of these pests is essential because they carry and spread various disease organisms. Many carry approximately 50 different microorganisms (such as Salmonella and Shigella), poliomyelitis, and Vibrio cholerae, the causative agent of cholera.Cockroaches spread undesirable organisms through contact with food, especially through biting and chewing. Although they prefer foods that contain a large amount of carbohydrates, they will feed on any substance that humans will consume, as well as on human waste, decaying materials, dead insects (including other cockroaches), shoe linings, and paper and wood materials. Cockroaches are most active in dark areas and at night, when less human activities exist.

German Cockroach (Blatella germanica)

The German cockroach is 13 to 20 mm long and pale brown, with two dark-brown stripes behind the head. Adults of both sexes have well-developed wings. The female carries the egg case protruding from the tip of the abdomen until hatching occurs.During the approximate lifetime of 9 months, an adult female produces approximately 130 offspring.

American Cockroach (Periplaneta americana)

Adults are reddish-brown to brown, and the young are pale brown. The female hides egg cases as soon as they are produced. This species produces more young than does the German cockroach because the adult female lives for 12 to 18 months, lays as many as 33 egg cases, and produces approximately 430 offspring.American cockroaches tend to inhabit open, wet areas, such as basements, sewers, drainage areas, and garbage areas, although this species may be found in storage rooms. They tend to stay in places that are slightly cooler and have larger cracks and crevices than does the German cockroach. 

Oriental Cockroach (Blatta orientalis)

The Oriental cockroach is shiny, dark brown to black and approximately 25 mm long. The wings are short in the male and absent in the female. Young cockroaches of this species are pale brown. Egg cases from the females are hidden soon after their formation. Females live 5 to 6 months and can produce one egg case per month for an approximate production of 80 cockroaches. 

Detection

Cockroaches may be found in any location where food is being processed, stored, pre-pared, or served. These insects tend to hide and lay eggs in dark, warm, difficult-to-clean areas. Their favorite harborages are small spaces in and between equipment and shelves, and under shelf liners. When cock-roaches need food that is not in these areas or when they are forced out by other cock-roaches, they come out into the light.

One of the easiest methods of checking for cockroach infestation is to enter a dark-ened production or storage area and turn on the lights. Also, a strong, oily odor that arises from a substance given off by certain glands of this insect can indicate the pres-ence of cockroaches. Cockroaches deposit their feces almost everywhere they have visited. These droppings are small, black or brown, and almost spherical.

Control

Control of this pest in food establishments should be a continuous operation through effective sanitation and use of chemicals. The most important form of con-trol is effective sanitation. These pests require food, water, and a sheltered hiding place. 

Exterior lighting, including parking lot lights, should consist of sodium-vapor bulbs yellow lights) that attract fewer insects than the standard incandescent-type Because these insects will eat almost anything, elimination of debris and maintenance of a tidy operation, including welfare facilities, through an ongoing sanitation program is the foundation for cock-roach control. Infestation is reduced through filling cracks in floors and walls sealants. 

Use of chemical control should follow sanitary practices. Chemical control can be handled through a pest control operator, but integrated chemical control and sanitary practices can be more effective and more economical. Diazinon offers potential for the control of cockroaches. Amidino hydrozone (Durs-ban) has been developed and sold as a bait, and can be effective against cockroaches that resist other poisonous compounds, but the use of this insecticide indoors is not accept-able. The liquid 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 commercial insecticides such as Raid. 

Other Insects

The housefly (Musca domestica), which is found throughout the world, is an even greater pest than the cockroach. 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. 

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. 

Prevention of entry into food establishments can be accomplished by prompt and thorough removal of waste materials from food areas. Air screens, mesh screens, and double doors discourage fly entry. To reduce attraction of flies around a food establishment, outdoor garbage storage should be as far away from doors as possible. If garbage is stored inside, this area should be separated by a wall from other locations and refrigerated to reduce decay and fly activity. Garbage should be stored in closed containers.

If flies have entered a facility, they can be controlled by the use of an electric flytrap or by other commercial traps, which attract adult flies to blue lights, killing them in electric grids. Electric flytraps should be used all day, and the catch basin should be cleaned daily. Chemical control through aerosols, sprays, or fogs, using chemicals such as pyrethrins can aid in fly control. Fruit flies (Drosophila melanogaster), which are smaller than the housefly, are also considered seasonal and are most abundant in late summer and fall. Adult fruit flies are 

approximately 2 to 3 mm long, with red eyes and light-brown bodies. They are attracted to fruit, especially decaying fruit. These pests are not attracted to sewage or animal waste; thus, they carry less harmful bacteria.

The life cycle and feeding habits of fruit flies are similar to those of houseflies, except that these insects are attracted specifically to fruits. These pests proliferate most rapidly in late summer and early fall, when rotting plants and fruits are more abundant. The life span of a fruit fly is approximately 1 month.

Total eradication of the fruit fly is difficult. Use of mesh screens and air screens will decrease entry into food establishments. When entry occurs, electric traps are some-what effective. One of the most effective methods of controlling these pests is to avoid accumulation of rotting fruits and fermenting foods.

The cigarette beetle, one of the most common stored-product insects, infests tobacco and dried plant materials such as herbs, spices, and dried flowers. Although this insect is frequently mistaken for the Drug-store Beetle, it is distinguished through its serrated antennae vs. the clubbed antennae of the Drugstore Beetle. A potential technology to control Cigarette Beetles is heat treatments. Thermal treatments in which ambient air 

temperature is increased to 48ºC and held for 24 hr is lethal for most insects Ants frequently nest in walls, especially around heat sources, such as hot-water pipes. If infestation is suspected, sponges saturated with syrup should be placed in a number of locations to serve as bait in determining where the insecticides should be applied. 

Silverfish and firebrats can reside in cracks, baseboards, window and doorframes, and between layers of pipe insulation. Because these pests thrive in undisturbed areas, their presence suggests inadequate and/or infrequent cleaning. Silverfish prefer a moist environment, e.g., basements and drains. The firebrat is more likely to be found in warmer environments, such as around steam pipes and furnaces.

Pheromone Traps

Pheromones are chemical substances emit-ted by insects to communicate with others of the same species. Types of pheromones include sex attractant, aggregation, fear, and territorial boundary markers. 

RODENTS

Rodents such as rats and mice are difficult to control because they have highly devel-oped senses of hearing, touch, and smell. These pests can also effectively identify new or unfamiliar objects in their environment and protect themselves against these changes in the surroundings.

Rats

Rats can force their entry through open-ings as small as a quarter, can climb vertical brick walls, and can jump up to a meter ver-tically and 1.2 meters horizontally. These rodents are strong swimmers and are known for their ability to swim up through toilet bowl traps and floor drains.Rats are dangerous and destructive. The most abundant kind of rat is the Rattus norvegicus gray-brown rodent, sometimes known as the sewer rat, barn rat, brown rat, or wharf rat. Roof rats will burrow or create nests in trees, vines, and other locations above the ground.

Mice

Mice, found frequently as the Musculus domesticus and M. musculus brevirostris varieties, are almost as cunning as rats. They are known to enter a building through a hole as small as a nickel. Mice are easily carried into food premises in crates and cartons. They are easier to trap than rats because they are less wary. Metal and wood-base snap traps are normally effective. 

Determination of Infestation

Rats and mice are nocturnal animals. Because they tend to be inactive during day-light hours, their presence is not always immediately detected. 

Control

Control of rodents, especially rats, is difficult because of their ability to adapt to the environment. The most effective method of rodent control is proper sanitation. Without an entrance to shelter and the presence of debris, which can nourish rodents, these pests cannot survive and will migrate to other locations. 

Prevention of Entry

Protection against rats is accomplished most effectively through the elimination of all possible entrances. Poorly fitting doors and improper masonry around external pipes can be flashed or covered with metal or filled with concrete to block entry of rodents. Vents, drains, and windows should be cov-ered with screens. 

Elimination of Rodent Shelters

Crowded storage rooms with poor house-keeping provide sheltered areas for rodents to build nests and reproduce. Rodents thrive in areas where garbage and other refuse are placed. 

Elimination of Rodent Food Sources

Proper storage of food and supplies com-bined with effective cleaning can aid in the elimination of food sources for rodents. 

Eradication

The more effective methods of eradicating rodents are poisoning, gassing, trapping, and ultrasonic devices.

Poisoning

Poisoning is an effective method of eradication; however, precautions are necessary because poison baits are hazardous if consumed by humans. Examples of rodenticides are the anticoagulants, such as 3-(α acetonyl-furfuryl)-4-hydroxycoumarin (fumarin), 3-(α acetonylbenzyl)-4-hydroxycoumarin (war-farin), 2-pivaloyl-1,3-indandione (pival), brodifacoum, bromodiolone, and chloropha-cinone. 

Tracking Powder

These compounds kill rats or, in the case of nontoxic powders, identify their presence and number. These powders may contain an anticoagulant or a single-dose poison. 

Gassing

This technique should be used only if other eradication methods are not effective. If this approach is necessary, rodent burrows should be gassed with a compound such as methyl bromide only by a professional exter-minator or a thoroughly trained employee. 

Trapping 

This is a slow but generally safe method of rodent eradication. Traps and bait stations should be tamper resistant so that non-target animals cannot get into them and placed at right angles to rodent runways, with the baited or trigger end toward the wall. 

Ultrasonic Devices

This eradication method uses sound waves that are supposed to repel the entry of rodents into areas where the device is installed. The most appropriate time to hit rodents with noise is when they first arrive

INTEGRATED PEST MANAGEMENT

Because of limitations of chemical pesti-cides, integrated pest control programs based on predicted ecological and economic conse-quences have been developed. Mostsingle insect control methods have not been suc-cessful, and insect resistance top pesticideshas become extensive. 

IPM implies that pests are “managed” and not necessarily eliminated. However, the ulti-mate objective of pest management in food processing is to prevent or eliminate pests. Several food processing and preparation firms have discovered the benefits of Components of a rodent integrated pest management program for food plants include: 

(1) exclusion and (2) sanitation. These components must comprise the main thrust of the rodent control program. Entry prevention is paramount to rodent control. In addition to the implementation of sanita-tion and rodent proofing efforts, the use of rodent baits and traps provide a preventive and remedial role in a rodent IPM program. Baits and traps are typically incorporated in a “perimeter defense” program. IPM empha-sizes sex pheromones because they are envi-ronmentally friendly, species specific, and 

effective at low doses.