Black Widow

Life Cycle and Habits: These spiders spin tangled webs of coarse silk in dark places, usually outdoors. Webs are usually built near the ground (occasionally within dwellings) normally in trash, rubble piles, under or around houses and outbuildings such as privies, sheds and garages. The female lays eggs in silken cocoons or sacs which are globular in shape and about 1/2-inch in diameter. Sacs are white at first, later turning pale brown. About 300 to 400 eggs per sac is common with 4 to 9 egg sacs produced during a summer. Normally, only 1 to 12 young survive after the egg incubation period of 14 to 30 days due to cannibalism.

Growth requires 2 to 4 months depending on availability of prey during which the females molt 6 to 8 times and the males 3 to 6 times. Females mature 92 days after egg sac emergence and live about 179 days longer, whereas males mature 71 days after emergence and live 30 days longer. Usually the female eats the male after mating. However, if females are well fed, most males get away to mate another day. Females hang belly upward, rarely leaving the web. Often cold weather and drought may drive these spiders into buildings. Prey caught in the web include a variety of insects (cockroaches and beetles) and other arthropods. The northern widow spider is similar to the black widow except its habitat is marginal land with sparse vegetation. It is found in stumps, hollow logs and piles of debris (occasionally indoors). The female black widow is shy and nocturnal in habit. She does not leave her hidden web voluntarily and is completely out of her area when away from the web. Outbreaks of black widows occur erratically. Some years an area may have thousands of widows and the next year they may be gone. Certain kinds of habitats such as sand dune areas may have black widows every year. Alternating warm and cold weather during the winter and spring months are detrimental to survival.

Bite Symptoms: According to Willia Gertsch, curator of spiders at the American Museum of Natural History, New York, the venom of the black widow spider is 15 times as toxic as the venom of the prairie rattlesnake. However, only a minute amount of the toxin is injected with a single bite by the spider, while the relatively large amount of injected rattlesnake venom results in about 15 to 25 percent mortality among those bitten.

The severity of a person's reaction to the bite depends on the area of the body bitten, amount of venom injected, depth of bite, seasonal changes and temperature. The bite feels like a pin prick or is not even felt. At first, there may be only slight local swelling and two faint red spots surrounded by local redness at the bite. Pain becomes intense in one to three hours and may continue up to 48 hours. Pain usually progresses from the bitten member up or down the arm or leg, finally localizing in the abdomen and back. The abdominal muscles may become rigid and board-like with severe cramps (resembles appendicitis). There may be pain in the muscles and soles of the feet, and eyelids may become swollen. Other symptoms may be nausea, profuse perspiration, tremors, labored breathing and speech, and vomiting. During this time, a feeble pulse, cold clammy skin, unconsciousness, convulsions and even death may result if the victim does not receive medical attention immediately. Additional complications may occur due to the infection of the bite. However, with some untreated individuals, symptoms may diminish in several hours and be gone in several days after agony. Bites are uncommon and serious long-term complications or death are rare. Only four deaths were officially attributed to black widow bites in the United States from 1960-69.

First Aid: If bitten, remain calm, collect the spider, if possible, for positive identification and get medical attention immediately. (Contact your physician, hospital and/or Poison Information Center.) First aid is of limited help. Application of a mild antiseptic such as iodine or hydrogen peroxide prevents infection.

Persons younger than 16 and older than 60, especially those with a heart condition, may require a hospital stay. (Health and lung failure may result in death.) A physician can give specific antivenom or calcium gluconate to relieve pain. Healthy people recover rapidly in two to five days.

Control Measures: Any pesticide treatments should be provided by a licensed Pest Control Operator of California,and a member of the Pest Control Operators of California, or of the state in which you live.

The black widow spider is shy and nocturnal in habit, usually staying in her hidden web. Although not aggressive, she may rush out and bite when her web is disturbed or when accidentally trapped in clothing or shoes. Many are associated with dry, undisturbed piles of firewood, old limbs, rock piles, bales of hay, wooden buildings and pit privies.

Prevention: Remove trash, old boxes, piles of lumber, old rubble piles and other unwanted items from under or around houses and outbuildings. Do not go barefoot or handle firewood without gloves. Install screens on doors and windows to prevent entry. Seal or caulk cracks and crevices where spiders can enter the house. Wash off the outside of the house or building, especially around window wells and other undisturbed places where webs are built. Spiders are fragile and easily damaged, so sweeping with a stiff broom will remove webbing and usually kill them. (Use Caution.)

Before using any pesticide, always read the label and follow directions and safety precautions.

This information is provided by Ohio State University.

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Earwig
They are often called "pincher bugs"

There are 22 species of earwigs in the United States of which 12 are introduced species. Only 4 or 5 species are common pests. The adult earwig is about 5/8 inches in length, and reddish brown in color. They can be found in homes, plants, piles of debris, and under rocks. If the population density is great enough some of them will be able to fly. They will invade homes and are often carried in to the home in newspapers they have crawled into. They are nocturnal and get their name from an old belief that they would enter the ears of sleeping people and bore into the brain. They live in moist, shady areas such as under stones, logs or in mulch. Adults will float in water for 24 hours.

FEEDING HABITS

Earwigs are omnivorous feeders and are very fond of plant food. They feed on a variety of plants and are considered minor pests of plants.

They also attack and devour other insect pests.

REPRODUCTION

Females will have 2 broods but commonly only have1 in North America They lay 30 to 55 eggs in a brood. The eggs hatch in about 70 days. Earwigs go through two phases during growth, nesting and free foraging. Most species overwinter in the adult form.

TREATMENT

Any treatment should be provided by a licensed Pest Control Operator of California, and a member of the Pest Control Operators of California. Contact Jeff's Pest Control Service for a "free inspection".

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Eastern Boxelder Bug

Boxelder bugs are generally black and red and have been identified in most states of the Union. Although other insects closely related to Boxelders look like them including the milkweed bug, none are likely to congregate in huge numbers like boxelder bugs. Members of this insect family feed on woody plants and herbs.

The boxelder bug got it's name because it was found to infest boxelder trees. These trees were planted in the west as settlers wanted quick growing shade trees. The availability of the vast numbers of boxelder trees allowed the boxelder bug to flourish. It now infests many other species of trees including maples, apple and almond. It seems to like several types of dead insects and fruit as well.

Boxelder bugs become a problem when they move into your yard or home. Once they begin to infest a tree, their population will grow from year to year. You will notice them congregating in massive numbers on the tree bark, limbs and the immediate ground around the tree. This congregation will occur in the spring and then again in the fall. In the spring, the boxelder emerges from its winter hibernation looking for a tree or plant that will supply food for the season. Young hatch in early summer and grow like roaches; they develop by instars. This means they go through several stages which resemble adults but will be smaller in size. As they molt and begin a new instar, they will become more and more like their reproducing parents.

In the fall, they will seek the south or warm side of the tree or plant they have been feeding on throughout the summer. As it cools more, boxelder bugs will take up residence in nearby homes and structures. Since they over- winter and do not die from year to year, a population can reach huge numbers. This "colony" will readily infest the same home from year to year once a successful winter shelter has been found. This migration into your home will ultimately lead to them getting inside.

Besides the damage to leaves, fruit and trees in your home, if allowed to infest your house they will invade relentlessly. Expect to have them climbing walls, clinging to curtains and buzzing around lights and ceilings throughout the winter. Since your home is heated, they don't need to "sleep" through the cold. Instead, they will forage around inside causing discomfort and being a nuisance until the spring.

TREATMENT

Any treatment should be provided by a licensed Pest Control Operator of California, and a member of the Pest Control Operators of California. Contact Jeff's Pest Control Service for a "free inspection".

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Argentine Ant

The Argentine ant, Linepithema humile (Mayr) -- formerly named Iridomyrex humilus -- is one of the more troublesome ants in California. Argentine ants are mainly a nuisance to people because the are often found indoors, forming wide noticeable lines or trails of ants into homes (See Figure 1).

These ants do not sting or bite. They are 2-3 mm in length and black to brown in color (See Figure 2). Argentine ant workers are all about the same size (monomorphic), in contrast to fire ants, where workers can be different sizes (polymorphic). Workers emit a faint musty odor when crushed.

Colonies are large and can contain many queens. Nests can be identified by the presence of brood. Brood are the larval and pupal stages of the ant. Brood are cream colored to white and immobile, so worker ants must carry them when they need to be moved. These ants probably arrived in the 1890s on coffee ships from Brazil. They rapidly spread throughout the United States. Entomologists have been trying to control these ants since the early 1900s. Argentine ants avoid the cold winters by inhabiting heated buildings.

Control Of Argentine Ants

Any treatment should be provided by a licensed Pest Control Operator of California, and a member of the Pest Control Operators of California. Contact Jeff's Pest Control Service for a "free inspection".

Argentine ants are difficult to control for the following reasons:

All ants are holometabolous (complete metamorphosis), having an egg, larval, pupal, and adult stage. Foraging adult ants are only a fraction of the total colony. Broadcast spraying around the perimeter of the house targets only the foraging adult ants in the colony. Control will be temporary since the colony will simply send out more foraging ants when others are killed. The colony supports multiple queens if ant populations are large. If a broadcast spray around the house is the primary method of control, the Argentine ant workers and queens will scatter. When the ants scatter in sufficient numbers, new colonies can be formed. The one main colony can split into several smaller ones, all of which have the potential to grow. Thus, broadcast spraying alone can make the problem worse. Unlike many other ant species, Argentine ants from different colonies do not fight. Therefore, their spread is less limited because they are not territorial. Even with their large colony size, they are quite mobile and can move from one area to another quickly. A broadcast spray may temporarily alleviate an Argentine ant infestation. But there is a good possibility that the ants will simply move to another area until the chemical breaks down. After the chemical breaks down, the ants will return because they are constantly scouting and foraging for food, water, and nesting sites. Heavy mulch against the walls of houses creates pockets of moisture that these ants need. Potted plants are a favorite nesting site. Moving infested pots into the house can create an indoor infestation.

These characteristics combine to create a pest control nightmare. Argentine ant control in the Southeast is an ongoing effort. Due to the large size of colonies and their rapid mobility, even if one colony is eliminated, another will move into the area over time. IPM Control Program

An Integrated Pest Management (IPM) approach offers a greater chance for control of the Argentine ant. An IPM approach incorporates all available control methods into a pest management program. IPM methods include identification, inspection, sanitation, exclusion, and chemical strategies.

Identification

For maximum control make sure you properly identify the ant pest. Different ants have different food preferences and different behaviors that will directly impact the efficiency of ant pest control.

Collection Tip - One way to collect ants for identification is to place a dab of honey or sugar water in the center of an index card. Place the index card into a plastic bag, then place the bag in the freezer. The cold temperatures will slow the ants down or kill them. When they are immobilized, the ants can be easily tapped into a vial of alcohol and submitted for identification.

Inspection

Contact Jeff's Pest Control Service for a "free inspection".

Sanitation

Eliminate sources of moisture (such as leaky faucets, plumbing, and free-standing water) and food because these ants are scavengers. Clean windows of dead insects. These ants will feed on dead insects. Remove the food source if ants are trailing to food. With a mild detergent, wipe ant trails after food is removed to erase the trail pheromone. The trail pheromone is a special chemical that foraging ants lay down to guide other foraging ants to food or to a new nesting place. Spray the ants with soapy water from a spray bottle. This will often temporarily halt ant problems if insecticide use is of concern around food or other sensitive areas. Soap breaks the surface tension of the water, causing the ants to drown. Check potted plants for ants before bringing the plants indoors. One way to check for ants is to water the soil thoroughly to force ants out of the soil. Physical Exclusion Caulk cracks and crevices in the house. Keep branches from coming in contact with your house (ants will walk on them into the house). Chemical

Professional Pest Control

Good pest control operators have the training, equipment, and materials necessary to perform ant control safely and effectively. You may prefer to have all of your pest control done by a professional because effective pest management required extensive knowledge of IPM tactics.

If you do contract the services of a pest control operator, ask questions about the plan to control your pest problems and get estimates from at least three reputable firms before choosing one.

Use pesticides ONLY according to the directions on the label. Follow all directions, precautions, and restrictions that are listed. Do not use pesticides for any other use than as directed by the label.

For more information, call Jeff's Pest Control Service (530) 247-1802. Or visit our web site at www.jeffspest.com

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German Cockroach

SIZE: Adults are about 5/8 inch long (17mm)

COLOR: Adult German cockroaches are light brown except for the shield behind the head marked with two dark stripes, which run lengthwise on the body. Young roaches are wingless and nearly black with a single light stripe running down the middle of the back. Egg capsules are light tan.

DESCRIPTION: German cockroaches, Blattella germanica (L.), are the most common roaches found in houses and restaurants. Most cockroaches have a flattened, oval shape, spiny legs, and long, filamentous antennae. Immature stages are smaller, have undeveloped wings and resemble the adults. They eat food of all kinds and may hitchhike into the house on egg cartons, soft drink cartons, sacks of potatoes or onions, used furniture, beer cases, etc.
 

HABITAT: They can develop into large populations and live throughout the house, especially in the kitchen and bathroom. During the day, these roaches may be found hiding clustered behind baseboard molding, in cracks around cabinets, closets or pantries, and in and under stoves, refrigerators and dishwashers. When seen during the day in clusters, the population is large.

LIFE CYCLE: German cockroach females, unlike most other roaches, carry the egg capsule protruding from their abdomen until the eggs are ready to hatch. The case is then placed in a secluded location, with the nymphs emerging one to two days later. A female may produce four to six cases during her lifetime, each containing 30 to 40 eggs. Eggs hatch in 28 to 30 days, and nymphs develop in 40 to 125 days. Female roaches live about 200 days and males not as long. The roach produces more eggs and has more generations per year (three to four) than other roaches, and only a few individuals are needed to develop into troublesome infestations.

TYPE OF DAMAGE: Roaches can foul food, damage wallpaper and books, eat glue from furniture, and produce an unpleasant odor. Some homeowners are allergic to roaches. The pests can contaminate food with certain bacterial diseases that result in food poisoning, dysentery, or diarrhea.

CONTROL: Any pesticide treatments should be provided by a licensed Pest Control Operator of California,and a member of the Pest Control Operators of California, or of the state in which you live.

Inspect sacks, cartons and boxes, etc., brought into the house, and destroy any roaches. Sanitation is critical in roach control. Clean up spilled foods and liquids, avoid leaving scraps of food on unwashed dishes and counter tops, keep food in tightly sealed containers, rinse cans and bottles before putting them in trash and transfer garbage outdoors into roach-proof receptacles.

Insecticides. Apply chemicals at roach hiding places. Enter a dark room quietly, turn on the light and watch where the roaches run. Spot treat these hiding places and known pathways, especially under and behind loose baseboards or molding strips and around pipes or conduits along the walls and through it. Do not treat entire floors, walls or ceilings. Roaches may hide around the kitchen sink or drain board, in cracks underneath cupboards and cabinets, inside the motor compartment of refrigerators, behind window and door frames, in radio and TV cabinets, and around closet and bookcase shelves. Surfaces where food is prepared should not be treated. Roaches in buildings with multiple dwellings usually require the treatment of other units as well.

INTERESTING FACTS: Without food or water, adults may die in two weeks, but they can live a month with water.

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Oriental Cockroach
SIZE: 1 & 1/4 inches long (31mm)

COLOR: Dark reddish brown to black

DESCRIPTION: When disturbed, may run rapidly and adults may fly. Females are wingless, and males have wings. Unlike other pest cockroaches, oriental cockroaches cannot climb up smooth surfaces (they lack sticky pads on their feet). Immature cockroaches resemble adults except that they are wingless.

HABITAT: Oriental cockroaches generally live in moist areas, but can survive in dry areas if they have access to water. They prefer cooler temperatures around 75 degrees Fahrenheit and can overwinter in protected areas outdoors where temperatures average 40 to 45 degrees Fahrenheit. These cockroaches are common in basements, crawl spaces, cracks and crevices of porches, foundations, and walkways adjacent to buildings. They feed on a wide variety of plant and animal material.

LIFE CYCLE: Females produce egg cases and carry them protruding from the tip of the abdomen for about two days. Egg cases are then generally glued to a surface in a hidden location. Egg cases are 3/8 inch long, brown, and purse shaped. Immature cockroaches emerge from egg cases in 6 to 8 weeks and require 6 to 12 months to mature. Adult cockroaches can live up to one year, during which females produce an average of 150 young.

TYPE OF DAMAGE: Not common in the home

CONTROL: Any pesticide treatments should be provided by a licensed Pest Control Operator of California,and a member of the Pest Control Operators of California, or of the state in which you live. Due to their large size and slow development, large infestations of these insects are not common within houses. However, during certain times of the year, they may move inside a house from outside sources. For example, in winter these cockroaches may move indoors, seeking warmer temperatures and food.

Cockroaches may enter houses via sewer connections, under doors, around utility pipes, air ducts, or other openings in the foundation. Exclusion is the best way to control this inward movement of cockroaches. Place fine mesh screening over crawl space vents and basement floor drains. Seal exterior doors with weather stripping. Fill gaps in walls and floors where pipes enter using steel wool and/or caulking compounds. Cockroach populations in basements can be reduced by decreasing dampness and applying insecticides in cracks and crevices where there is evidence of cockroach activity (presence of egg cases, dead cockroaches, brown fecal smears).

Cockroach populations around the perimeter of houses are more difficult to control. First, limit the availability of food and water. Place garbage in trash cans, not plastic bags (plastic bags rip easily). Divert water from gutters at least 3 feet away from the foundation. Secondly, reduce hiding places for the cockroaches. Do not stack firewood or debris next to the foundation. Make a visual inspection about one to two hours after sunset to locate cracks and crevices in the building from which cockroaches are emerging. Spray these areas with insecticide and seal the cracks and crevices, if possible.

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Fleas and Flea Control

Fleas

There are four stages in the life cycle of the flea: egg, larva (three stages), pupa (cocoon), and adult.

Adult fleas prefer to live on the host animal, but are often dislodged by scratching. Eggs are laid on the animal, but are quite smooth and easily fall off into the environment. Larva hatch from the egg and undergo approximately three molts, progressively becoming larger. Larva live off of organic debris, including flea dirt, the dried blood-feces of the adult flea.

The third stage of the flea larva makes a cocoon where the adult flea develops. The egg, larval, and pupal stages almost always take place in the environment off of the animal, where the microenvironment is often ideal for growth. These larvae and cocoons are found deep in carpeted areas or areas with a layer of organic material (e.g., a garden or flower bed). They are protected from insecticides in this hard-to-reach area.

Adult fleas hatch from the cocoon when proper stimulation is present. The stimuli include: vibration, increased carbon dioxide levels, heat, and motion. The adult can emerge from the cocoon in a very short time period...less than a second....and immediately jump to find a proper host. Once on the host they feed on blood obtained by biting through the skin.

An egg may develop into an adult flea within 14 days if conditions are ideal. Each fertilized female may lay as many as 25 eggs per day....more than 800 in her lifetime. In just thirty days, 25 adult female fleas can multiply to as many as a quarter of a million fleas!

The main flea affecting the dog and cat is the cat flea, Ctenocephalides felis. There is a dog flea also that occasionally is responsible for flea infestations, but the majority of the time, C. felis is the flea found on dogs and cats. Fleas are insects that are highly developed and can reproduce in copious amounts when environmental conditions are ideal. High humidity and high relative temperatures provide that ideal environment.

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Background Information on the Biology of Ticks
Larisa Vredevoe, Ph.D, Deparment of Entomology, University of California, Davis

Soft tick (left) and Hard tick (right)

Ticks are blood feeding external parasites of mammals, birds, and reptiles throughout the world. Approximately 850 species have been described worldwide (Furman and Loomis 1984). There are two well established families of ticks, the Ixodidae (hard ticks), and Argasidae (soft ticks). Both are important vectors of disease causing agents to humans and animals throughout the world. Ticks transmit the widest variety of pathogens of any blood sucking arthropod, including bacteria, rickettsiae, protozoa, and viruses. Some human diseases of current interest in the United States caused by tick-borne pathogens include Lyme disease, ehrlichiosis, babesiosis, rocky mountain spotted fever, tularemia, and tick-borne relapsing fever.

Hard Ticks: Family Ixodidae

Hard ticks have three distinct life stages. Larvae which emerge from the egg have six legs. After obtaining a blood meal from a vertebrate host, they molt to the nymphal stage and acquire eight legs. Nymphs feed and molt to the next and final stage - the adult, which also has eight legs. After feeding once more, the adult female hard ticks lay one batch of thousands of eggs and then die. Only one blood meal is taken during each of the three life stages. The time to completion of the entire life cycle may vary from less than a year in tropical regions to over three years in cold climates, where certain stages may enter diapause until hosts are again available. Many hard ticks can go for several months without feeding if not unduly duressed by environmental conditions.

Scanning Electron Micrograph
of Tick Mouthparts

The mouthparts of hard ticks are readily visible from above. There are three visible components: the two outside jointed parts are the highly mobile palps; between these are paired chelicerae, which protect the center rod-shaped structure, the hypostome. The palps move laterally while the tick is feeding and do not enter the skin of the host. The rough hypostome has many beak-like projections on it. This is the structure which plunges into the host's skin while feeding. The backward directed projections prevent easy removal of the attached tick. In addition, most hard ticks secrete a cement-like substance produced by the salivary glands which literally glues the feeding tick in place; the substance dissolves after feeding is complete.

Questing Hard Tick
(Ixodes scapularis)

Hard ticks seek hosts by an interesting behavior called "questing." Questing ticks crawl up the stems of grass or perch on the edges of leaves on the ground in a typical posture with the front legs extended, especially in response to a host passing by. Certain biochemicals such as carbon dioxide as well as heat and movement serve as stimuli for questing behavior. Subsequently, these ticks climb on to a potential host which brushes against their extended front legs. Hard ticks are most commonly collected for research by the use of "flags" or "drags" which are made from 1 m square pieces of roughly textured fabric such as fleece or flannel attached to a rod handle. The flags are slowly dragged across the surface of vegetation to collect questing ticks. Hard ticks feed for extended periods of time on their hosts, varying from several days to weeks, depending on such factors as life stage, host type, and species of tick. The outside surface, or cuticle, of hard ticks actually grows to accommodate the large volume of blood ingested, which, in adult ticks, may be anywhere from 200-600 times their unfed body weight (Sonenshine 1991).

Lifecycles of Hard Ticks

Hard ticks have a variety of life histories with respect to optimizing their chance of contact with an appropriate host to ensure survival. Some ticks feed on only one host throughout all three life stages. These ticks are called one host ticks. This type of tick remains on one host during the larval and nymphal stages, until they become adults, and females drop off the host after feeding to lay their batch of eggs. Other ticks feed on two hosts during their lives and are called two host ticks. This type of tick feeds and remains on the first host during the larval and nymphal life stages, and then drops off and attaches to a different host as an adult for its final blood meal. The adult female then drops off after feeding to lay eggs. Finally, many ticks feed on three hosts, one during each life stage, and are appropriately named three host ticks. These ticks drop off and reattach to a new host during each life stage, until finally the adult females lay their batch of eggs. In each case, the fed adult stage is terminal, that is, after laying one batch of eggs the female dies, and after the male has reproduced, he dies as well.

Soft Ticks: Family Argasidae

The life stages of soft ticks are not readily distinguishable. The first life stage to come out of the egg, a six legged larva, takes a blood meal from a host, and molts to the first nymphal stage. Unlike hard ticks, many soft ticks go through multiple nymphal stages, gradually increasing in size until the final molt to the adult stage. Some soft ticks pass through up to seven nymphal molts before they become adults. Soft ticks feed several times during each life stage, and females lay multiple small batches of eggs between blood meals during their lives. The time to completion of the entire life cycle is generally much longer than that of hard ticks, lasting over several years. Additionally, many soft ticks have an uncanny resistance to starvation, and can survive for many years without a blood meal (Furman and Loomis 1984).

The mouthparts of soft ticks are are not readily visible from above. There are three visible components: the two outside jointed parts are the highly mobile palps; between these are paired chelicerae, which protect the center rod-shaped structure, the hypostome. The palps move laterally while the tick is feeding and do not enter the skin of the host. The rough hypostome has many beak-like projections on it. This is the structure which plunges into the host's skin while feeding. The backward directed projections prevent easy removal of the attached tick.

Some soft ticks seek hosts by questing on low-lying vegetation, but the vast majority are nest parasites, residing in sheltered environments such as burrows, caves, or nests. Certain biochemicals such as carbon dioxide as well as heat and movement serve as stimuli for host seeking behavior. Soft ticks feed for short periods of time on their hosts, varying from several minutes to days, depending on such factors as life stage, host type, and species of tick. The feeding behavior of many soft ticks can be compared to that of fleas or bedbugs, as once established, they reside in the nest of the host, feeding rapidly when the host returns and disturbs the contents. The outside surface, or cuticle, of soft ticks expands, but does not grow to accommodate the large volume of blood ingested, which may be anywhere from 5-10 times their unfed body weight (Sonenshine 1991).

Soft ticks can be readily collected via dry ice traps. Blocks of dry ice emit large amounts of carbon dioxide, a host seeking stimulant. Traps are set in and around nesting areas of animal hosts. Soft ticks can be observed running along the surface of the ground towards the trap and are collected by hand, or inside a collection chamber in the trap. Many types of soft ticks can be artificially fed in the laboratory, thus reducing or eliminating the use of animals for certain studies. Some (ie: Ornithodorus coriaceus) will feed through sausage casings filled with almost any type of mammal blood heated up to 37° C. Others can be fed blood through various types of membranes in the presence of biochemical and environmental feeding stimulants such as ATP, carbon dioxide, heat, and animal fur (Sonenshine 1993).

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Lyme Disease

Introduction:

Lyme disease is an infection caused by the corkscrew-shaped bacteria Borrelia burgdorferi that are transmitted by the bite of deer ticks (Ixodes scapularis) and western black-legged ticks (Ixodes pacificus). The deer tick, which normally feeds on the white-footed mouse, the white-tailed deer, other mammals, and birds, is responsible for transmitting Lyme disease bacteria to humans in the northeastern and north-central United States. On the Pacific Coast, the bacteria are transmitted to humans by the western black-legged tick.

Ixodes ticks are much smaller than common dog and cattle ticks. In their larval and nymphal stages, they are no bigger than a pinhead. Adult ticks are slightly larger. Ticks feed on blood by inserting their mouth parts (not their whole bodies) into the skin of a host animal. They are slow feeders: a complete blood meal can take several days. As they feed, their bodies slowly enlarge.

Risk:

The number of annually reported cases of Lyme disease in the United States has increased about 25-fold since national surveillance began in 1982, and a mean of approximately 12,500 cases annually were reported by states to the Centers for Disease Control and Prevention (CDC) from 1993-1997. In the United States, the disease is mostly localized to states in the northeastern, mid-Atlantic, and upper north-central regions, and to several counties in northwestern California.

Most B. burgdorferi infections are thought to result from periresidential exposure to infected ticks during property maintenance, recreation, and leisure activities. Thus, individuals who live or work in residential areas surrounded by woods or overgrown brush infested by vector ticks are at risk of getting Lyme disease. In addition, persons who participate in recreational activities away from home such as hiking, camping, fishing and hunting in tick habitat, and persons who engage in outdoor occupations, such as landscaping, brush clearing, forestry, and wildlife and parks management in endemic areas may also be at risk of getting Lyme disease.

References:

Centers for Disease Control and Prevention. Methods used for creating a national Lyme disease risk map. MMWR. 1999;48(RR07);21-24.

Dennis DT. Epidemiology, ecology, and prevention of Lyme disease.
Rahn DW, Evans J eds. Lyme disease.
Philadelphia, PA: American College of Physicians; 1998;7-34.

Nadelman RB and Wormser GP. Lyme borreliosis. Lancet. 1998;352:557-65.

Centers for Disease Control and Prevention. Lyme disease -- United States, 1996. MMWR. 1997;45(1).

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Lice

Head lice are very small wingless insects (about 1/16" to 1/8") that live on the human scalp and in the hair. They are more commonly found on young children than adults. They are generally tan in color but since they feed by sucking blood they may turn a brown or reddish color after feeding. They move by crawling; they can't fly or jump like fleas. They're sensitive to light; so if you look for them by parting the hair they'll try to keep out of the light in the thicker parts of the hair.

    An adult female may lay 3-5 nits (egg casings) per day which are glued so strongly to hair shafts that only fingernails or a specially designed 'nit' comb will remove them (normal brushing or washing won't get it!). The nits are laid on hair shafts very close to the scalp (for moisture and warmth) and will hatch out after 7-10 days. After hatching, the new lice mature in about 2-3 weeks and can lay a new generation of nits.

Nits range in color from a fairly dark brown to a very light tan, depending on how old they are and whether or not they have hatched out or have been killed by some previous treatment. If they've already hatched out, they will tend to be very light, sometimes almost white, in color. As a general rule of thumb, nits found on hair shafts more than about 3/4" from the scalp are usually 'old' nits that are either dead or have already hatched out. It is not unusual for hundreds of nits to be found in the hair of an infested child, particularly if the child has been infested for some time.

Most people who have to deal with these little beasts usually end up feeling as though their city or state is, to quote one frustrated Mom, "The Head Lice Capital of the World!" Not so! In the last two years, we've heard from every state in the U.S, 10 provinces in Canada, and more than 57 other countries and territories, as widely distributed as Chile, South Africa, Iceland, Japan, and New Zealand! So no matter where you are, you're probably not being picked on any more than anyone else... but I know that doesn't help very much!

Why Are They A Problem?

Head lice cause a number of minor problems... itching, the possibility of secondary infections, and redness or small bite marks (like mosquito bites) on the scalp. Very rarely, a secondary infection might result in swollen glands in the neck or under the arms. Other problems include:

From the viewpoint of the Child:

- Embarrassment
- Time lost from school activities when sent home.

From the viewpoint of the Parent:

- Embarrassment
- Money spent and time lost in treating infestations
- Frustration at not knowing how to handle recurring infestations
- A feeling that the school is 'singling out' their child

From the viewpoint of the Teacher:

- Time lost from class activities while dealing with this problem
- Frustration at being the target of some parents' anger
- Fear that they will 'catch it

If this list appears to focus mostly on the psychological or societal impacts rather than on medical issues, there is a good reason for this, which we'll address in the next section.

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Norway Rat

Although some people think of mice and rats as child and parent, these two are different organisms. Their biology is different and their life history is different. Though there is limited space here, it's important to point out a few key distinguishing characteristics.

The body of a mouse will grow from as little as 2" to as much as 3-1/2" when fully grown. The rat's body will be as small as 7" but grow to a length of nearly 10". Mice will weight as little as a mere 1/2 ounce to up to 1 ounce whereas a large rat may weigh more than a pound.

Color will vary in both mice and rats though they are most commonly seen as gray to brown. A mouse will squeeze through an opening as small as 1/2". Both rodents have poor eyesight and rely on their acute sense of smell and hearing to compensate.

Management of Rodent Problems

The most effective means employed to control rodent is exclusion. If openings are eliminated, in most cases, rodents cannot get into a structure. However, sometimes a dirt floor may exist inside a structure to which a burrowing rodent may find entry. Exclusion or rodent-proofing, requires strong material through which rodents may not be able to gnaw such as concrete, sheet metal, coarse grade steel wool, hardware cloth and crushed glass. We sell a repair product called Stuf-It, a copper mesh that is malleable and rust proof, for this purpose.

The next step in controlling rodents is eliminating food sources. People are often surprised to find out that foodstuffs that had long been forgotten are the source of food for rodents. The bird seed up in the attic or in the garage or a box of food which fell down behind a shelf somewhere. Therefore, it is important to seek those things out. Also, any food in boxes or bags as well as the daily garbage must be protected by placing these items into impervious containers of metal or glass. Outside, a thourough inspection of the premise is important to keep rodents away. Identify any harborage areas and openings that can allow easy access.

Finally, the removal of rodents from a structure may be achieved in a number of different ways. There are electronic devices which emits very high frequency ultrasonic sounds which frighten rodents out of a building.

Trapping would be another possible step in rodent control. There are "humane" traps which may capture rodents without harming them. There are also snap traps and glue traps which may be used for this purpose.

Finally, the most common rodent control technique is rodenticide application using anti-coagulant type baits. These kill the rodent by thinning the blood until the animal hemorrhages internally. The animal suffers some dizziness, then dies from the loss of blood.

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