CARPENTER ANTS

Camponotus pennsylvanicus (DeGeer)

The black carpenter ant is a common invader of homes in the northeastern United States. In their natural habitat, carpenter ants aid in the decomposition of dead, decaying trees. They normally nest in logs, stumps, and hollow trees. However, the large, dark-colored workers often invade homes in search of food. These ants seldom tunnel into dry, sound wood, but they may excavate moist, rotting wood and other soft materials (such as foamed plastic insulation board) to make satellite nests. Rarely will the expansion of a nest into a building’s wooden timbers cause structural damage. Homes built in wooded areas are especially subject to infestation.

DESCRIPTION

Figure 1. Black carpenter ant worker

Steve Jacobs, PSU Entomology

Figure 2. Black carpenter ant queenJ.Kalisch, U of Nebraska

Figure 3. Eastern subterranean termite

workersJ.Kalisch, U of Nebraska

Carpenter ants and termites are social insects that live in colonies and excavate wood. Because of this, homeowners may mistake one for the other. It is important to distinguish between the two because each requires different methods of control.

Carpenter Ants• Workers (Fig. 1) are wingless, dark shiny brown to black in color, and 1/4 to 1/2 inch in length. They may be seen crawling around inside a residence.• Winged reproductive forms (Fig. 2) resemble workers in color and shape but are up to 3/4 inch long.• The body is constricted between the thorax and the abdomen.• The antennae are elbowed.• The front wing of a reproductive ant is longer than the hind wing.

Eastern Subterranean Termites• Workers (Fig. 3) are creamy-white, wingless, and 1/8 to 1/4 inch in length. They live hidden from view, unless their tunnels are exposed.• Reproductive forms are brown or black, have wings, and measure about 3/8 to 1/2 inch in length.• The body is not constricted between the thorax and the abdomen.• The antennae are straight with beadlike segments.• The front and hind wings of a reproductive termite are about equal in length.

LIFE HISTORY

A carpenter ant colony has one wingless queen and many sterile, wingless, female workers. It also has white, legless larvae and, at certain times, winged females and males. The eggs are white and the pupae cocoons are tan. Usually, a colony does not produce winged males and queens (the reproductives) until it is several years old and has about 2,000 to 3,000 workers. Approximately 200 to 400 winged ants develop in the summer, remain in the nest through the winter, and leave the nest the following spring or early summer. The ants hibernate (are inactive) during the winter. They will be active, however, if a nest is located in a heated portion of a building.

Winged males and females emerge from established colonies on warm days in the spring and early summer. Mating occurs during a brief flight, after which the male dies, and the female (queen) removes her wings and searches for a suitable nesting site. The nest is usually located in a cavity in the soft, moist, decaying wood of a hollow tree, stump, or log. A new queen lays fifteen to twenty eggs, which produce the first brood of offspring. The whitish, soft-bodied, legless

larvae later become the sterile female workers.

Development from egg to worker requires a minimum of about sixty days. The workers of the first brood are small because they are nourished only from food reserves that are stored in the queen’s body. Once these workers become adults, the queen’s only function is to lay eggs. The adult workers forage for food, enlarge the nest, and feed and care for the queen and subsequent larvae. They eat dead insects and other small invertebrates as well as the honeydew secreted by aphids and scale insects. They regurgitate this food and feed the larvae and the queen. Workers of succeeding broods are larger because the foraging workers feed them.

DIAGNOSIS

The presence of large (1/2 inch), wingless, dark-colored ants inside a home is usually the first sign of an infestation. However, this does not necessarily mean that a nest is present indoors. The nest may actually be located outside, near the building. Thus, foraging workers from the nest may be entering the structure in search of food and water. These worker ants, which usually emerge at night, will feed on meats and foods containing sugar and fat. During the summer, homeowners can use a flashlight to look for foraging workers at night. Check basement, attic, garage and building exterior from May through July between the hours of 10:00 p.m. and 2:00 a.m. It may be possible to follow the ants back to their nest or discover where they are entering the house. If numerous winged reproductive ants are found at windows inside the house, they probably came from an indoor nest.

The indoor nest(s) may have originated from one or more parent colonies outside the home. The parent colony is often located in a tree, log, or waste wood within 100 yards of the house. Workers travel between the satellite and parent colonies. To eliminate the ants, the parent and the satellite nests must be found and eliminated. Common indoor nest locations include porch pillars and supporting timbers, sills, girders, joists, wall studs, window and door casings, and under insulation between ceiling joists or wall studs. Check areas where the wood may be wet or damp because of poor ventilation, a leaking roof, defective flashing, overflowing or leaking gutters and downspouts, condensation from water pipes, or leaking bathtubs, showers, and appliances. In homes, the ants typically do not excavate wood for nest construction, but make their nests in hollow areas of ceilings, walls, or floors. They will tunnel through sound structural timbers to gain access to a void on the other side, but this has little effect on the structural integrity of the timber.

Homeowners should watch for ants that are foraging indoors and try to find their nests. Look for piles of coarse, stringy wood particles, dead insect parts and other debris that are sifting from cracks in the siding, behind moldings, in the basement and attic, and under porches. Because carpenter ants do not consume the wood as food, excavated particles are dumped outside the nest. Unlike termites, the tunnels or galleries of carpenter ants are smooth-sided and contain no soil particles or fecal pellets. Satellite colonies within homes can sometimes be located by listening for a rustling sound in walls and ceilings using a stethoscope or inverted water glass to hear the ants.

 

PREVENTION

 

Remove stumps, logs, and waste wood within 100 yards of the building. Do not allow vegetation, especially evergreen shrubs and trees, to be in contact with the house. Store firewood away from the house and off of the ground, and bring it into the house only when needed. Keep wooden parts of the house and other structures dry by making necessary repairs to roofs, flashing, gutters, and downspouts. Replace any water-damaged, decaying wood. Usually, carpenter ants will not infest wood that is sound and has moisture content of less than 15 percent. Keep exterior wood surfaces painted and sealed. Seal holes through which pipes and wires enter the house. Use pressure-treated (CCA) wood for parts of the structure that will be in contact with the soil. Place a moisture barrier (plastic sheet) over soil in crawl spaces and under wooden porches, and provide adequate ventilation for such spaces.

 MANAGEMENT

 

Homeowners that want to try their hand at controlling the ants should strive to locate and eliminate all of the ants’ nests. The parent and satellite colonies must be destroyed or the ants will reappear in a few days or weeks. Products that are not toxic to mammals are preferred for use by homeowners in and around the home. Dust formulations of diatomaceous earth, silica aerogel, or boric acid have no or low mammalian toxicity and may be blown into nests and cavities to kill the ants. The repair of structural problems and replacement of damaged wood should accompany the elimination of nests. Nests outside of the building should be eliminated by removing the infested wood or tree, or by treating it with an insecticide product labeled for such use.  Unfortunately, it is unlikely that the satellite colony can be eliminated without the use of one or more of the materials applied by professional pest management companies.

The application of insecticide sprays, dusts, or baits to areas where the foraging ants may come in contact with them will give partial control and may eliminate the colony.  The use of carpenter ant baits may be effective if the pest management professional is diligent in locating the ants’ trails and in reapplying baits as they become depleted.  Frequently, for one reason or another, the ants will ignore the baits.  One of the newer insecticides available to pest management companies is applied as an outside perimeter treatment.  It is not repellent to the ants and usually only one treatment is required.  Your pest management professional should have this material available.

Citronella Ants Acanthomyops species

Acanthomyops interjectus, the larger yellow antAcanthomyops claviger, the smaller yellow ant

 The citronella ants get their name from the lemon verbena or citronella odor they emit when threatened. It is most noticeable when the ants are crushed. They are subterranean insects that feed on the honeydew (excretions) of aphids and mealybugs feeding on the roots of shrubs.

Both the larger and the smaller yellow ant are found throughout much of the continental United States. They are very common in the eastern United States and are frequently confused with termites when they swarm into the living areas of homes. In both species, the swarmers (winged ants) may vary in color from the more common light yellow to a dark reddish-yellow or light brown. The workers are typically yellow with less color variation than the swarmers.

Description

Of the two species, the larger yellow ant (A. interjectus) is the most commonly encountered in Pennsylvania homes (Fig. 1). The workers are 4 to 4.5 mm long and have 12-segmented antennae, with the scape (first antennal segment) just reaching the top of the head. They have a single node to the pedicel connecting the thorax and abdomen, with sparse, erect hairs on the head, thorax, and abdomen.

The swarmers are approximately twice the size of the workers and have dark, smoke-colored wings. Like the workers, they can also vary in color from a light yellow to light reddish-brown.

Other than its size (workers are 3 to 4 mm), the smaller yellow ant looks similar to the larger yellow ant.

Fig. 1. Citronella ant

Life History

Little is known about the inner workings of these subterranean colonies. The ants are believed to tend aphids (much as dairy farmers would cows) and collect the honeydew they excrete. They are not known to forage for other food sources. Nest sites may include open woods, pastures and fallow fields, gardens, lawns, and next to house foundations. Also, some colonies are located beneath concrete slabs and large rocks, and in and beneath rotting logs.

Swarms may occur in and around homes any time of the year. The most common swarming occurs in mid- to late summer, but swarmers have been collected from homes during late autumn and early spring. These early and late season swarms are possibly an abnormality created by the warmer soils under and adjacent to heated structures.

Management

Citronella ants should be considered only as a nuisance pest species. Normally, they go unnoticed unless the swarmers enter through expansion cracks in slabs or around door openings. Although these intrusions may alarm homeowners, the ants will not reproduce within the home nor will they attack stored goods or structures.

In some cases, swarms may occur repeatedly and attempts should be made to locate the colony or colonies. Colonies typically have mounds of soil around the openings where excavated soil is deposited. These mounds can be treated by injecting an insecticide into the holes. Although numerous insecticides are labeled for ant control, many of these can only be used by licensed individuals. Therefore, a professional pest control company should be contacted because they can use materials not available to the general public and have access to specialized application equipment.

AMERICAN COCKROACHES Periplaneta americana (L.)

Cockroaches are among the most common of insects. Fossil evidence indicates that cockroaches have been on earth for over 300 million years. They are considered one of the most successful groups of animals. Because cockroaches are so adaptable, they have successfully adjusted to living with humans. About 3,500 species of cockroaches exist worldwide, with 55 species found in the United States. Only four species are common pests in Pennsylvania structures. These are the German, brown-banded, Oriental, and American cockroaches. A fifth species, the Pennsylvania wood cockroach is an occasional nuisance pest in some locations.

Description and Behavior

The American cockroach is the largest of the species common to Pennsylvania. This species often becomes abundant in city dumps and is most common in the basements and steam tunnels of restaurants, bakeries, food-processing facilities, and grocery stores.

Adults are approximately 1-1/2 inches long and reddish brown, with fully developed wings that cover the entire length of the abdomen (Fig. 1). Both male and female are fully winged. The wings of the male extend slightly beyond the tip of the abdomen, while those of the female are about the same length as the abdomen. Nymphs are similar in appearance but are smaller and do not have wings. American cockroaches are capable of flying but rarely do in northern areas of the United States. The American cockroach can be identified by its large size and reddish brown color with faded yellow edges on the thorax. Figure 1.

Photograph of American cockroach life stages.

 When indoors, the nymphs and adults are usually found in dark, warm and moist areas of basements and crawl spaces, and in and around bathtubs, clothes hampers, floor drains, pipe chases, and sewers. They are also common around the manholes of sewers, and on the undersides of metal covers over large sump pumps. In the north, this cockroach is often associated with steam heat tunnels. Where steam heat tunnels are not found, the American cockroach is restricted primarily to large institutional buildings. It has also been observed migrating from one building to another during warm months in the north. Occasionally, the cockroaches infest sanitary landfills and can survive Pennsylvania winters because of the warmth generated within the piles of trash.

American cockroaches feed on a variety of foods, with an apparent preference for decaying organic matter. The adults can survive two or three months without food but only about a month without water.

Life History

American cockroaches have three developmental stages: egg, nymph, and adult. The eggs are laid in capsules that are dark brown, symmetrically shaped, and about 5/16 inch long. The female drops her egg capsule within a day after it is formed. She often drops it in a suitable location near a food source or in a protected area. Each capsule averages 14 to 16 eggs. Usually one capsule is produced each week and is often glued to a hidden surface with secretions from the female’s mouth. Each female produces from 15 to 90 egg capsules.

The length of the egg stage varies from 29 to 58 days. At room temperature, nymphs hatch out in 50 to 55 days. Young nymphs are grayish brown and after the first few molts become reddish brown. The nymphal stage varies in length from 160 to 971 days. The number of offspring per year averages 800. Under ideal conditions an adult female can live up to 15 months, males for a somewhat shorter period.

Injury / Damage

American cockroaches feed upon a great variety of materials such as cheese, beer, leather, bakery products, starch in bookbindings, manuscripts, glue, hair, flakes of dried skin, dead animals, plant materials, soiled clothing, and glossy paper with starch sizing. The most important aspect of cockroach damage derives from the insects’ habit of feeding and harboring in damp and unsanitary places such as sewers, garbage disposals, kitchens, bathrooms, and indoor storage indoors. Filth from these sources is spread by cockroaches to food supplies, food preparation surfaces, dishes, utensils, and other surfaces. Cockroaches contaminate far more food than they are able to eat.

From various points in their bodies American cockroaches, and cockroaches in general, produce odorous secretions that can affect the flavor of various foods. When populations are high, these secretions may result in a characteristic odor in the general region of the infestation. Disease-producing organisms such as bacteria, protozoa, and viruses have been found in cockroach bodies. Different forms of gastroenteritis (food poisoning, dysentery, diarrhea, etc.) appear to be the principal diseases transmitted by these cockroaches. These disease-causing organisms are carried on the legs and bodies of cockroaches, and are deposited on food and utensils as cockroaches forage. Cockroach excrement and cast skins also contain a number of allergens, to which many people exhibit allergic responses such as skin rashes, watery eyes, congestion of nasal passages, asthma, and sneezing.

 

Management Strategies

 

Survey - To control American cockroaches, it is important to do a thorough inspection. A cockroach survey (trapping) is sometimes necessary to determine the extent of an infestation, as even a thorough inspection does not always reveal all cockroach harborages or foraging areas. Cockroach surveys involve placing sticky traps at strategic locations within the building. Whenever possible place survey traps either against a wall or in a corner of the floor, a shelf, a drawer, or under equipment and counters. Most commercially available traps come complete with bait to encourage cockroaches to enter. One week of trapping with a sufficient number of trapping sites usually provides enough information for effective control.

Sanitation, Structural Modifications, and Repairs - Modifying the interior environment—removing food, moisture, and harborages available to cockroaches—is the first step in treatment. Eliminating cockroach harborages involves caulking in closets and cabinets, caulking under the sink, etc., or making similar structural repairs in the kitchen, bathroom, and other areas of the house.

Cockroaches typically enter homes via boxes, grocery bags, suitcases, furniture, etc. To prevent the insects from establishing a breeding population, clean up all spilled food materials, including crumbs on the floor. Do not leave dirty dishes overnight. Store items such as cereal, crackers, cookies, flour, sugar, and bread in airtight containers.

Chemical Control - Dusts such as boric acid, silica aerogel, and diatomaceous earth can be applied to voids and other harborages such as cracks and crevices. Do not apply dusts to wet or damp areas. Dusts should be applied lightly because heavy deposits may repel cockroaches. Do not place dusts where children or pets could come into contact with them. Take care to keep children away from areas treated with boric acid. Take precautions to assure that the dusts do not contaminate food.

Baiting can be an effective method to control or eliminate American cockroaches. Baits containing hydramethylnon, sulfluramid, boric acid, or abamectin should provide a high level of control when applied to those areas where cockroaches harbor. Care should be taken to closely follow the label instructions for use.

The use of residual sprays or aerosol foggers within a structure is of little value in controlling American cockroaches. In fact, these applications may disperse the cockroaches making control difficult and lengthy.

Warning

Pesticides are poisonous. Read and follow directions and safety precautions on labels. Handle carefully and store in original labeled containers out of the reach of children, pets, and livestock. Dispose of empty containers right away, in a safe manner and place. Do not contaminate forage, streams, or ponds.

BED BUGSCimex lectularius L.

Click here forAcrobat Reader Version

All members of the bed bug family feed on the blood of birds or mammals. The bed bug, Cimex lectularius, attacks man, as does the Eastern bat bed bug, Cimex adjunctus. Other species exist that attack bats, pigeons, and rodents. Bed bugs are active only at night, usually just before dawn. During the day, they hide in cracks and crevices in walls, floors, beds, and furniture. When only a few bed bugs are present, they live close to human sleeping areas; when numerous, they can be found in many rooms of the house. A characteristic “bed bug odor” is frequently present in a home infested with bed bugs.

 Image 1. Adult bed bug

Steve Jacobs - Penn StateEntomology Department

 LIFE HISTORY, DESCRIPTION & BIOLOGY

   

Bed bugs are oval, chestnut-brown insects and are flattened from top to bottom. Adult bed bugs (Fig. 1) measure about ¼ inch in length. The mouthparts are shaped into an elongated proboscis, which, when not in use, is held directed backward underneath the body. When a bug is ready to feed, the proboscis is extended forward and the stylets within are thrust into the skin of a host. Mated female bed bugs deposit their eggs in their resting places. One female will produce about 345 eggs during her lifespan.

Bed bugs grow by molting several times. Nymphs look very much like the adults, except they are smaller and not sexually mature. There are five nymphal molts, and each nymph must have a blood meal to be able to molt to the next stage. Adults feed once a week on average but feed many times during their four-month or longer lifespan.

Bed bugs often come into a home via secondhand articles and furniture. They may also migrate between homes via wires, plumbing, or rain gutters. In addition, since warehouses, trucks, and railroad cars may be infested, common bed bugs can infest homes by stowing away on new furniture stored or shipped from these places.

The Eastern bat bed bug comes into homes in the spring with colonies of bats. They can be found in the living quarters of homes in many of the same places as common bed bugs, but the source of the infestation is located within walls or attic areas.

Image 2. Adult bed bug

 INJURY

 

Despite the fact that the bed bug can acquire many human disease organisms during feeding, there have been no documented cases of disease transmission as a result of bites. However, their bites can produce irritating, itching, and burning sensations. Bed bugs feed rapidly, becoming engorged in less than ten minutes. The act of biting is usually not felt, but later there is an allergic reaction to the protein found in the bed bug’s saliva. A colorless wheal or lump develops at the bite location; in contrast, flea bites have reddish centers. Discomfort from bed bug bites may last a week or more. Occasional bites indicate a beginning light infestation of adults; many bites result from a heavy, long-standing population of nymphs and adults. 

MANAGEMENT  NOTE: It is not advisable for homeowners to attempt to treat for bed bugs. Most of the necessary insecticides are only for sale to and use by professional pest-management companies. If homeowners try to control these bugs with over-the-counter products, the bed bugs likely will become dispersed, resulting in a more difficult treatment required at a later date.

Bed bugs become established in structures when they hitch a ride in boxes, baggage, furniture, bedding, laundry, and in and on clothing worn by people coming from infested sites. Poultry workers can carry bed bugs to their residences from their places of work. Bat bugs, poultry bugs, swallow bugs, and others are typically transported to new roosts by the principal host. An accurate identification of the bed bug species involved is essential to an effective control strategy. Many control failures can be traced to an incorrect identification.

Bed bugs hides in cracks, crevices, and seams during the day. They prefer narrow crevices with a rough surface where their legs and backs touch the opposing surfaces. Bed bugs cannot climb glass or smooth, plastic surfaces. Wood and paper surfaces are preferred to either stone, metal, or plaster; however, in the absence of preferred sites or during high population numbers, the latter will also be utilized. The aforementioned cracks and crevices should be filled with

appropriate fillers, such as caulking.

Bugs will sometimes hide in the crevices of upholstered furniture and mattresses created by folds, buttons, and cording. Thoroughly vacuum all upholstery—including the undersides—mattresses, and pillows. Launder bedding and dry in a warm air dryer. Mattresses, upholstered furniture, and cushions can be treated with “dry” steam. It is best to use two professional-grade steamers with low vapor flow rates, each with one-gallon capacities. This allows one unit to always be hot between water refills. The steam should exit through a wand with multiple ports to reduce the risk of blowing the bugs out of their hiding places. Using an infrared thermometer, make certain that the area just treated is at least 176°F. (80°C). Depending on the steam unit used, the wand should pass over the surface of the fabric at about a foot every ten seconds. Two products, Bedlam® (phenothrin w/ pyrodone) and Sterifab® (phenothrin w/ isopropanol), are registered for application to mattresses, pet bedding, carpets, and other sensitive areas as allowed by the labeling. Bedlam® has been shown to have ovicidal properties with up to 90 percent of bed bug eggs not hatching. Both materials have excellent contact kill and demonstrate residual activity for up to seven days.

Pesticides can be applied to cracks and crevices of dressers, wooden bed frames and headboards, door and window trim, baseboards, and similar sites. Three classes of insecticides are reviewed: (1) Botanical insecticides containing natural pyrethrins will repel insects and can “knock down” bed bugs for a period of time, but natural pyrethrins quickly deteriorate and do not provide the necessary residual action of some other materials. Finishes on furniture and other wood items may be damaged from the petroleum carriers contained in aerosol pyrethrins. (2) Inorganic materials such as silica gel, boric acid, and diatomaceous earth will provide long-term control, provided they are used in an environment with low humidity. These inorganic materials have very low repellency, a long residual life, and can provide good control if thoroughly applied to cracks and crevices. However, they are typically white in color and may leave the surface of items with an undesirable film unless they are carefully applied. (3) Synthetic pyrethroids such as deltamethrin, lambda-cyhalothrin and others can provide good control if they are carefully and thoroughly applied to suspected bed bug harborages. They are relatively long-lived residuals and will not damage materials that are not harmed by water. Consideration should be given to the fact that people typically spend in excess of eight hours per day in the bedroom. If the insecticides are properly applied, there should be little risk of exposure. Recent studies have demonstrated that some populations of bed bugs are exhibiting resistance/tolerance to several of the more commonly used synthetic pyrethroid insecticides. However, the microencapsulated materials such as Onslaught® (esfenvalerate) and Demand CS (lamba-cyhalothrin), and a suspended concentrate, Suspend SC (deltamethrin), can offer rapid reduction of susceptible populations. Bed bugs have not shown resistance to a relatively new material, Phantom® (chlorfenapyr). However, chlorfenapyr may require ten days kill the bugs. During this ten-day period it is important to realize that the bugs may still be active and females may wander and deposit viable eggs in other locations. These products are injected or sprayed into cracks and crevices or bed frames, baseboards, dressers and drawers, and as spot treatments to carpet along walls. An insect growth regulator, (S)-hydroprene (Gentrol®), interferes with the bugs’ development and renders the adults sterile. Since it does not kill adults or nymphs it must be used in conjunction with a contact insecticide such as Phantom®, Suspend®, Demand®, and so forth. Gentrol® is applied to the same locations as these contact insecticides.

For bed bug infestations other than the common bed bug, C. lectularius, the bird or bat that has occupied the structure should be removed and measures taken to prevent the reentry of the animals. The materials listed for the common bed bug will also control the other species, providing that treatment considerations be given to the potential harborages (e.g., crevices between rafters, cracks in chimney flues) that will differ from the common bed bug.

WARNING 

BIRD MITESClick here for

Acrobat Reader Version 

Bird mites are very tiny, flattened parasitic arthropods in the order Acari. They belong to two closely related genera in two families; Dermanyssus species in Dermanyssidae (Fig. 1), and Ornithonyssus species in Macronyssidae. Bird mites have piercing mouthparts that enable them to take blood meals from their bird hosts. Although the mites will inadvertently bite people, they cannot reproduce without their bird hosts.

DESCRIPTION

Bird mites have five stages: egg, larva, protonymph, deutonymph and adult. The larvae have three pair of legs; the nymphs and adults have four pair. Adults are about 0.7 to 1 mm in length and are just barely visible to the naked eye. Unless they are moving, they are extremely difficult to see. The color is translucent white until they take a blood meal after which the mites are reddish mahogany to brown. Mite eggs are white, oval and cannot be seen without the aid of magnification. The same applies to the larvae and nymphs.

LIFE HISTORY / BEHAVIOR

Most bird mite species can complete development in five to twelve days with optimal temperatures and host presence. This short life cycle makes it is possible for mite populations to attain tens of thousands of mites in bird nests during the rearing of young birds. If the population is too large (or if the fledglings vacate the nest or perish), the mites will migrate in mass to locate an alternative host. It is during this migration that mites can and do enter the living quarters of people. Some mites (i.e. Dermanyssus gallinae, the chicken mite) can survive for several months without taking a blood meal; the northern fowl mite, Ornithonyssus sylviarum, for several weeks. However, the mites do not appear to survive for more than several days in the reduced humidity (<35%) environs typically found in air-conditioned or de-humidified homes. 

CLINICAL SYMPTOMOLOGY  As the mites search for an alternative host, they will crawl onto the skin and conduct an exploratory bite to test the appropriateness of the host. The mite will move on, possibly trying the host again, but will not feed. These bites are felt as a “prick” and a resultant rash and itching, sometimes intense, will occur. Some individuals are apparently capable of sensing the crawling of the mites on the skin. The irritation produced by the bite is enhanced by the injection of the mite’s saliva that can cause a localized histamine response. Differential diagnosis can be difficult in the absence of mite specimens and can easily be misdiagnosed as non-descript “insect bites.” Most bird mite infestations occur during the late spring to early summer when bird nests are in abundance. When investigating claims of "insect bites" during this time of year, physicians, entomologists, and pest management professionals should inquire as to the presence of bird nests in attics, soffits, rain gutters, shrubbery next to buildings, and on window sills and air conditioners. 

MANAGEMENT

 Birds should be discouraged from building nests in or adjacent to buildings. Close all openings large enough for birds to enter attics, soffits and similar areas. Install hardware cloth, sheet metal, or other materials to prevent birds from nesting and roosting on porches, breezeways and other exterior sites. Disrupt nest-building efforts by removing partially completed nests in shrubbery and on air conditioners and windowsills.

If mites are detected in the structure, locate the bird nest source. Remove the nest. Do not spray insecticides on the interior living areas. Insecticidal sprays may be useful in attics, inside soffits and around exterior nest locations. Use a synthetic pyrethroid such as bifenthrin, cyfluthrin, cypermethrin, deltamethrin or lambda-cyhalothrin. Mites in living areas can be removed with a damp cloth (ethyl alcohol works well on non-porous surfaces) or with a vacuum cleaner.

CLOTHES MOTHTinea pellionella, casemaking clothes mothTineola bisselliella, webbing clothes moth

Click here for Acrobat Reader Version 

INTRODUCTION Both the webbing clothes moth and the casemaking clothes moth are worldwide in distribution, feed on animal by-products such as furs, wool carpets, and tapestries, and can cause damage to stored woolen clothing. Although the webbing clothes moth is more common in Pennsylvania and other northern states, both can be found in Pennsylvania.

DESCRIPTION

The webbing clothes moth adults (Fig. 1) are about 7–8 mm in length when the wings are folded back over the body. The wings are a golden buff color with a fringe of long hairs on the margins. The head has a tuft of reddish hairs. Mature larvae are 12–13 mm long and feed on woolens beneath a constructed blanket of silk, feces, and pieces of the food source. The bodies are white or cream with a brown head capsule. The larvae have no ocelli (eyes). It is common to find the larvae feeding under cuffs, collars, and other hidden parts of clothing.

The casemaking clothes moth adults (Fig. 2) are similar in size and shape to the webbing clothes moth although the top of the head has no tuft of reddish hairs. The wings (at least in fresh specimens) exhibit three dark spots, but on older moths, the spots are frequently rubbed off. The larvae are 10–12 mm long and are colored similarly to the webbing clothes moth larvae. However, they have one ocellus (eye) on each side of the head. Unlike the webbing clothes moth larvae, the casemaking clothes moths construct a tube or bag that they occupy and carry with them. This tube, made of silk and pieces of wool, may be very difficult to see because it is the same color as the item being eaten.

 

La pupa de la polilla del estuche.

Life HISTORY

Clothes moths mate and deposit their eggs usually within 1–2 days of emergence from the pupae. The females do not live long (3–16 days) after egg deposition although the males of the webbing clothes moth can survive for about one month. The eggs hatch in 4–10 days in the summer, but may take up to three or more weeks in the winter. Depending on temperature and humidity, total developmental time (from egg to adult) varies from one to three months and can extend up to three or more years in some situations.

Males and females from both species shun light and are frequently overlooked by homeowners. When discovered, the adults are more likely to try to escape by running rapidly than by flying.

MANAGEMENT

 

Proper diagnosis of the pest is the first step in gaining control. Woolens damaged by the clothes moth exhibit furrows in the surface, which is caused by the larvae’s habit of “grazing.” Occasionally, and during heavy infestations, the woolens will have holes. When larvae infest furs or hairbrushes, they clip off the individual hairs close to the surface. Larvae can infest cast pet hairs that are trapped under baseboards or in the air return vents of heating systems. They also have been found in vacant wasp nests and feed on insects that have died in wall voids or attics. Because of this, it is important to practice thorough cleaning of the home using a good vacuum cleaner. In many instances clothes moths can be prevented and/or controlled solely by vacuuming. Be sure to dispose of the vacuum bag when finished.

The webbing clothes moth will feed on hair, wool, fur, feathers, and similar animal products. Synthetics, cottons, and other plant materials are not attacked by the webbing clothes moth larvae unless these items are stained with food or body oils. The casemaking clothes moths will attack any of the following: felts; dried carcasses or taxidermy mounts; wool clothing, carpets, or tapestries; feathers; furs; and plant-derived materials such as dried herbs, tobacco, tea, hemp, pharmaceuticals, and seeds and

seed products.

If infested, clothing, blankets, and tapestries should be laundered or dry cleaned. Small carpets and throw rugs can be beaten and brushed while hanging from an outside line to remove most, if not all, eggs and larvae. Large area rugs and carpets should be treated by professional pest management companies (pest control companies). Never apply pesticides to clothing or bedding. Before using any pesticide, thoroughly read the label and do not apply to any carpet, upholstery, or other site unless it is specifically listed in the directions for use.

Human LiceHead louse - Pediculus humanus capitus

Body louse - Pediculus humanus humanusCrab or pubic louse - Pthirus pubis

Click here for Acrobat Reader Version 

Introduction

Since no fossils of lice have ever been found we can only speculate when they originated. We do know the ancient Egyptians and Greeks wrote of them and they were found on prehistoric American Indian mummies. There are three kinds of lice which feed on man.

1. The head louse (Pediculus humanus capitus) 2. The body louse (Pediculus humanus humanus) 3. The crab or pubic louse (Pthirus pubis)

Head and body lice are very much alike, however, body lice are slightly larger. These lice have abdomens longer than they are broad and their six legs are equal in size. In contrast, the abdomen of the crab louse is about as wide or even slightly wider than its length, and the second and third pairs of legs are thicker than the first pair. Crab lice are much smaller than head and body lice.

Depending on temperature, lice eggs (nits) usually hatch into nymphs within ten days. There are three nymphal stages, the third followed by the adult stage. All stages must have blood meals if they are to survive and continue their development. Adult lice live about 30 days.

Public Health Implications

Louse-transmitted diseases are presently not a serious threat in the United States. In other parts of the world, however, lice do transmit typhus fever (a

disease which has killed many millions of people), epidemic relapsing fever, and trench fever.

Lice cause much discomfort to humans due to their bites, which are irritating,

causing sleeplessness. Scratching often leads to secondary bacterial infections.

Head Lice The female head louse will deposit from 50 to l50 eggs or nits in her lifetime.

Head lice glue their eggs to the base of hairs. Only one nit is glued to any one hair. Eggs hatch in five to ten days when the temperature is between 95× and

100×F. Below 74×F, most eggs will not hatch.

People finding nits on hairs wonder if they are old nits which have already hatched or new nits which may still hatch. Since human hair grows about 1/2 inch

per month, any nits found on a hair 1/4 of an inch from the scalp would be approximately 16-days old, and would have hatched already, or will not hatch.

These nits are glued tightly to the hair shaft and can only be removed by combing. A special fine-toothed comb must be used which has teeth 0.l mm

apart. A vinegar rinse is not effective.

The life cycle for the head louse (from egg to adult) takes from 16 to 21 days.

Body Lice Body lice spend most of their time on the underclothing, next to the body,

particularly along the seams. From here they periodically visit the hosts’ body for blood. They usually glue their eggs (up to 300 in a lifetime) to the fibers of

clothing, but may occasionally glue them to body hairs as does the head louse.

Crab Lice These lice are found mostly in the hair of the pubic area. They may also be found under the armpits, in the beard or mustache and on the eyebrows and eyelashes. Their development from egg to adult normally requires from 30 to 41 days. Adult

crab lice live about 30 days. Females deposit 30-50 eggs (in her lifetime).

How Do People Get Lice?

Anyone can get lice no matter how clean they are about their personal hygiene and their homes. Lice do not feed on dirt; they feed on blood! People get lice from people. They don’t come from pets. (Dog and cat lice do not infest man.)

Head lice are transferred between persons who share items such as hats, hairbrushes, combs, or wigs.

Body lice spread from clothing, particularly underclothing. If infested clothing is left lying about, body lice can migrate and thus, spread to other clothes and people.

Crab lice usually are transmitted from person to person by sexual contact, however, they can be found on toilet seats and in beds, and from there, spread to

people.

Management

Shampoo products containing either prescription or over-the-counter preparations are the standard treatment for head lice. Body lice and crab lice are controlled using lotions which contain an insecticide. Contact your physician or pharmacist to determine which of these products will be most effective.

Washing clothes in hot water, 123oF or higher, will kill any body lice and their nits. Clothes which can’t be laundered should be dry cleaned. Body lice can often be controlled by frequent changes and washings of clothes. Head lice, on the other hand, are not killed by frequent showers. Cutting the hair will not eliminate head lice (unless the head is actually shaved).

FOUR COMMON TICKS OF PENNSYLVANIATick-borne Diseases and Prevention, Tick

Distributions, Life Histories and Control

BACKGROUND INFORMATION

 Ticks, of which there are more than 500 species world-wide, are parasitic arthropods closely related to mites. Most ticks feed on the blood of warm-blooded mammals but some species also feed on birds, reptiles and even amphibians. Fish are apparently the only vertebrates not plagued by these little blood-suckers.

Many species of ticks can transmit diseases (zoonoses) from an infected host to other uninfected hosts. Some of the more frequently transmitted organisms include parasitic worms, viruses, bacteria, spirochetes and rickettsias. The most important of these to Pennsylvanians are spirochetes which cause Lyme disease, and rickettsias which cause Rocky Mountain spotted fever.

Currently, more than 25 species of ticks have been identified in Pennsylvania. Of these, four species account for nearly 90 percent of all submissions to Penn State for identification. The four ticks are: 1) the American dog tick, Dermacentor variablis; 2) the blacklegged tick, Ixodes scapularis; 3) the lone star tick, Amblyomma americanum; and 4) a ground hog tick, Ixodes cookei.   

American dog tickDermacentor variabilis

Distribution: Dermacentor variabilis is found in the eastern two-thirds of the United States from Nova Scotia to the Gulf Coast. It is the most commonly encountered tick in Pennsylvania and occurs in most counties.

Hosts: The immature stages are frequently found on small rodents such as meadow mice. The adults are frequently found on dogs (hence the name) and can be recognized by the distinctive white markings on their back. The American dog tick may become greatly engorged, achieving the size of a grape. In addition to man, the other hosts are cat, cattle, donkey, hog, horse, mule, sheep, coyote, deer, fox, wolf, wildcat, badger, opossum, rabbit raccoon, rat, skunk, squirrel, weasel and ground hog.

Diseases: American dog ticks are the major carrier of Rocky Mountain spotted fever, which is less common than Lyme disease, but a potentially more serious illness. This tick has also been known to transmit tularemia, and to cause tick paralysis. It cannot transmit the spirochetes responsible for Lyme disease.

Image of Americandog tick female.

© SBJacobsPSU Entomology

   

Blacklegged tickIxodes scapularis

Distribution: Ixodes scapularis is found throughout the eastern United States and in parts of the northern mid-west in wooded, brushy locations. It has been expanding its range in recent years and can now be found in most of the counties in Pennsylvania. Three areas of the state are heavily infested: (1) the southeastern portion of Pennsylvania (in those counties southeast of a line through Wayne to Adams counties) (2) the north central counties of Elk, Clearfield and Cameron; and (3) Presque Isle in Erie county.

Hosts: The larvae feed on birds and small animals such as squirrels mice and grouse; the nymphs also feed on small mammals and birds, while the adults prefer deer. Any stage of the blacklegged tick can feed on humans.

Diseases: This tick is well known as the vector of Lyme disease and has also been known to carry human babesiosis - a fairly rare, generally mild febrile disease. The blacklegged tick typically requires in excess of 24 hrs. of attachment before it can transmit the causative agent for Lyme disease.

Note: This tick was previously known as the “deer tick, Ixodes dammini.” Recently, studies have proven that this tick is not a new species, and therefore the original designation is used. I. dammini is no longer a valid species designation.

 

Image of blacklegged tick

female.© SBJacobs

PSU Entomology

Lone star tickAmblyomma americanum

Distribution: Amblyomma americanum is widely distributed in the United States. It is commonly found from Texas north to Missouri and eastward to the Atlantic coast. It is found most often in the southern counties of Pennsylvania near urbanized areas. The lone star tick may be active from early spring to late fall.

Hosts: The larvae feed on a variety of small animals, while the nymphs feed on many small and larger animals. Adults are usually found on larger animals, and all stages are found on deer and will feed on humans.

Diseases: The lone star tick is known to vector tularemia, Rocky Mountain spotted fever, and causes tick paralysis in man and in dogs. Although regarded as a poor vector for Lyme disease, there are anecdotal accounts of erythema migrans developing at the site of attachment. In Pennsylvania, this tick is known to transmit only rocky mountain spotted fever.

Lone star tick Photo by Jim Kalisch

Univ. of NebraskaEntomology Department

   Groundhog tick

Ixodes cookei

Distribution: Ixodes cookei is found east of the Rockies from Texas to South Dakota and northeastwards through Maine. This tick is less common, or at least less commonly encountered, than the three previously mentioned ticks. It is, however, a relatively common tick in portions of western and northern Pennsylvania.

Hosts: This tick is very host-specific for groundhogs, but occasionally is found on birds, small animals or humans.

Diseases: It is not considered to be an important vector of Lyme disease because it tends to feed only on groundhogs. In laboratory studies, the larval I. cookei would not feed on Peromyscus sp. and as such is probably not a good candidate as a vector for Lyme borreliosis. Additionally, it is not a known vector for any other zoonoses

 

Image of groundhog tick

nymph© SBJacobs

PSU Entomology.

DISEASES

Lyme Disease

 

Lyme Disease or Lyme borreliosis is an infection caused by the spirochete Borrelia burgdorferi which is transmitted to humans by ixodid ticks. It is a multisystem illness characterized initially by erythema migrans and a series of common nonspecific complaints and symptoms including headache, fever, sore throat, nausea, etc. and to late phase symptoms which left untreated may progress to debilitating rheumatologic, cardiac, and neurologic conditions, but rarely directly to death.

A skin lesion appears as a red macule or papule and expands to form a large round lesion, over a period of days or weeks. The center of this lesion often tends to progressively clear. This condition is called erythema migrans (EM) and for the purpose of CDC surveillance definition, the lesion must reach a size of 5 cm (approximately 2 inches). Associated or secondary lesions may be present. This symptom is generally accompanied with intermittent fatigue, fever, headache, a stiff neck, arthralgias or myalgias.

Later musculoskeletal, nervous, and cardiovascular systems exhibit more profound manifestations. Weeks or months after the initial erythema migrans there is recurrent swelling of the joints which may become a chronic condition in one or more sites. Lymphocytic meningitis, cranial neuritis, bilateral facial palsy (Bell’s palsy), radiculoneuropathy and occasionally encephalomyelitis occur alone or in combinations. Atrioventricular conduction problems may arise which may lead to myocarditis. Additional symptoms of arthralgia, myalgia, fibromyalgia, headache, fatigue, stiff neck, palpitations, and bundle branch block may be associated, but are not confirmative of Lyme disease.

Rocky Mountain Spotted Fever (RMSF)

RMSF was first recognized in the United States during the 1890s, but until the 1930s it was reported only in the Rocky Mountains. By 1963, over 90 percent of all cases were reported east of the Rockies. In the west, the disease was limited mainly to men who worked and spent time in wooded areas, while in the east, cases occur when people come in contact with infected ticks from their pets or in their yards.

RMSF is caused by a rickettsia, Rickettsia rickettsii. The vector in the east is the American dog tick (Dermacentor variabilis), but the disease is also carried by the lone star tick and the Rocky Mountain wood tick (Dermacentor andersoni). Symptoms include a red-purple-black rash, usually on the wrists and ankles, which appears from two days to two weeks after infection. A fever, headaches, and malaise also are characteristic. Broad-spectrum antibiotics are used to treat RMSF. Diagnosis can be made with a blood test, but treatment should not wait for serological confirmation, as fatalities do occur.

Tularemia

Also known as rabbit fever, tularemia is carried by the Rocky Mountain wood tick, the rabbit tick (Haemaphysalis leporispalustris), the lone star tick, and the American dog tick. Rabbits serve as a reservoir for the bacterium, Francisella tularensis. The number of cases in the United States has dropped considerably in the last 50 years. In 1989 only 144 cases were reported, compared to nearly 2,300 cases in 1939.

Symptoms include a sudden onset of fever, chills, loss of appetite, general body aches, and swollen lymph nodes. An ulcer forms at the site of the bite. Serological tests are used in diagnosis, and treatment consists of antibiotics. If not treated, symptoms intensify. Tularemia causes a few deaths each year.

Babesiosis

Caused by a protozoan, Babesia microti, the disease is transmitted by the blacklegged tick (Ixodes scapularis). Fatigue and loss of appetite are followed by a fever with chills, muscle aches, and headaches. In more extreme cases, blood may appear in the urine. Babesiosis is more severe in older people and those with no spleen. Fatalities can occur in older patients. The condition has been treated with drugs that are used to treat malaria, but with limited success. Generally, the disease is self-limiting and symptoms disappear on their own.

Erlichiosis

Most common in the southern United States, erlichiosis usually occurs in rural areas during May, June, and July. It is caused by a rickettsia belonging to the genus Erlichia. The clinical signs are similar to those of Rocky Mountain spotted fever: chills, headache, body aches, fever, and a rash, though the rash occurs with a lower frequency. Often the symptoms are very mild. Tetracyclines are the treatment, as with RMSF. Originally identified as an animal disease, erlichiosis was believed to be limited to dogs.

Tick Paralysis

Tick paralysis is not a disease, but a condition caused by toxins that a tick injects into its host during feeding. Most mammals seem to be affected, but smaller and younger mammals (children) are more susceptible.

Symptoms begin a day or two after initial attachment. The victim loses coordination and sensation in the extremities. The paralysis progresses in severity, the legs and arms becoming useless; the face may lose sensation; and speech becomes slurred. If the breathing center of the brain is affected, the victim may die. If the tick or ticks are found and removed, recovery begins immediately, and the effects disappear within a day.

Generally, this condition is associated with ticks attached around the head area, particularly at the base of the skull. Ticks that have been implicated in tick paralysis in the United States are the Rocky Mountain wood tick, the lone star tick, and the American dog tick. However, not all members of a species cause tick paralysis. The toxin that causes this condition is part of the salivary fluid that the tick injects. Because the problem is associated with ticks attached on the head, and because recovery is quick upon removal of the tick, it is theorized that the toxin acts locally and is broken down in the body rapidly. Tick paralysis occurs only sporadically; the important thing is to be aware that it exists and, when symptoms occur, to attempt to find the tick and remove it.

PREVENTION AND CONTROL

The best advice for preventing Lyme disease and other tick-borne diseases is to:

1. Wear protective light-colored clothing while outdoors, including a broad-brimmed hat, a long-sleeved shirt, and long pants tucked into the socks;

2. Check the body daily for the presence of ticks;

3. Use tick repellents, DEET, or permethrins;

4. Use forceps or tweezers to carefully remove ticks attached to the skin. Apply gentle, constant retraction of the tick where it attaches to the skin (not the body of the tick);

5. Seek immediate medical attention if signs or symptoms or early Lyme disease appear.

The best way to avoid attachment of a blacklegged tick is to stay out of wooded or brushy areas in known Lyme disease counties. This option is not always realistic. Repellents such as DEET (N,N-Diethyl-meta-toluamide) offer considerable protection if applied to clothing and exposed skin. Because of recent concern over adverse reactions in a few individuals, sprays with no more than 35 percent DEET are recommended.An effective acaricide, Permanone™, contains the synthetic pyrethroid permethrin and is applied as a spray to clothing. It is not approved for use on skin. Long-sleeved shirts and long pants tucked into socks also aid in preventing tick bites. Light-colored clothing helps to detect the dark-colored tick provided the wearer inspects for ticks intermittently.

Hunters and hikers increase their risk of encountering a blacklegged tick by following deer trails and by resting on the forest floor. Studies in New York have shown that a high density of nymphal blacklegged ticks is present in leaf litter. Adult ticks more often are collected from narrow forest trails than from general sites throughout the forest, and they

are more prevalent in high, brushy vegetation .

Hunters should be cautious when harvesting deer. The urine, blood, and liver could carry the spirochetes, which can enter through cuts in the hands, although this is highly unlikely. Cooking destroys the bacteria and eliminates any danger of getting Lyme disease from eating venison. There are no documented cases of transmission through handling or consuming deer flesh.

Self-examination is recommended after spending time in infested areas. If an embedded tick is found, it should be removed with fine tweezers by grasping the head and pulling with steady firm pressure. The tick should not be grabbed in the middle of its body because the gut contents may be expelled into the skin. The use of heat (lit match, cigarette, etc.), or petroleum jelly is NOT recommended to force the tick out. These methods will irritate the tick, and may cause it to regurgitate its stomach contents into the individual, thereby increasing the possibility of infection.

LYME DISEASE AND DOGS

Most dogs, even though they have been exposed to Borrelia burgdorferi, never exhibit any signs of Lyme disease. In certain highly endemic areas of New York and New Jersey dogs exhibit almost a 90% rate of exposure as evidenced by serosurvey. However, only about 4% of the dogs exhibit signs of Lyme disease including lameness, poor appetite and fever. Treatment of these animals with antibiotics typically results in rapid recovery.

A few dogs can develop lesions on the kidneys (Lyme nephropathy) and may not respond to antibiotic treatment. Interestingly, dogs susceptible to this condition may not be protected by the Lyme vaccines currently available. In fact, there are concerns that the vaccine may possibly sensitize a genetically predisposed individual to having a more intense immune-mediated reaction to Lyme antigens, or the vaccine may add to antigen-antibody complex deposition in tissues (Meryl P. Littman, VMD, DACVIM, University of Pennsylvania - personal comm. 2001).

Kennels, runs, or yards can be treated with a variety of residual insecticides labeled for tick control at these locations. Tick pesticides that are labeled for exterior tick control include bifenthrin, cyfluthrin, deltamethrin, esfenvalerate, permethrin and tralomethrin. Follow all label instructions. Do not apply materials labeled for kennels, yards and other exterior sites on your pets.

GLOSSARY OF MEDICAL/ENTOMOLOGICAL TERMINOLOGY

Arthralgias: a pain in a joint; it may be in a single joint such as the knee or in several joints, and commonly involves the larger joints.

Atrioventricular Conduction: conveyance from the atruim to the ventricle of nerve impulses which stimulate the heart muscle.

Bell’s Palsy: a paralysis of the facial nerve (Cranial nerve VII), causing a muscular weakness on one side of the face. Associated may be the inability to close an eye, loss of taste sensation and hearing impairment causing sounds to be excessively loud.

Cranial Neuritis: an inflammation or degeneration of the nerves that arise directly from the brain; a manifestation of Lyme disease.

Encephalomyelitis: an acute inflammation of the brain and spinal cord. Several arthroborne viruses are vectored by mosquitoes, ticks and mites.

Erythema Migrans (EM): a characteristic skin lesion of Lyme disease which occurs in 60% to 83% of patients with the disease. The lesion appears about three to thirty days after the tick bite. It initially commences with a red macule (spot) or papule (raised area) at the site of the tick bite which expands over a period of days or weeks into a flat annular lesion (measuring at least 5 cm), usually with a partially clear central area. The border of the lesion is inflamed and migrates outward, causing a bulls-eye-like pattern around the

site of the original bite. The average size of the lesion is 15 cm, but lesions 4 times as large have been reported. Untreated, the lesion will fade after weeks or months; on the average after a month. Thereafter in the affected area, dead tissue will scale and slough off and eventually the area regains normal coloration. This does not mean an end to the disease.

Febrile: with a fever.

Fibromyalgia Syndrome: a variant of the chronic fatigue syndrome that causes widespread musculoskeletal pain and may occur one to five months or later after early Lyme disease is observed.

Ixodid: belonging to the genus Ixodes.

Larva (pl., larvae): the first developmental stage in tick development. The larvae have three pairs of legs. In a tick embryo the rudiments of all four pairs of legs are present. However, the fourth pair of legs reside as masses of latent cells beneath the cuticle of a larva. During the quiescent molting period that precedes the nymphal stage, the development of the fourth pair of legs takes place. Entomologists generally restrict the usage of larva to developmental stage of insects with complex of complex metamorphosis; the term nymph is used for the developmental stage of insects with gradual metamorphosis. The acarological usage is at variance with the entomological usage.

Meningitis: an inflammation of the meninges due to an infection by viruses or bacteria.

Malaise: a vague feeling of bodily discomfort.

Myalgia: pain in the muscles.

Myocarditis: an inflammation of the muscular walls of the heart or myocardium and usually the pericardium (membrane surrounding the heart) as well.

Nymph: As used by acarologists, the term nymph has a significantly different meaning from common entomological usage. A nymphal ixodid tick is the second stage in morphological development, occurs following a larval stage and precedes the adult. Upon molting from larva to nymph, ticks gain a fourth pair of legs. As used in entomology, the nymph is the immature stage of those insects that have gradual or incomplete metamorphosis.

Palpitations: rapid, skipped, fluttering or abnormal rhythm of heart.

Radiculoneuropathy: a disease of central nervous system, usually causing weakness and numbness. The distribution of the symptoms are in an area corresponding to one or more nerve roots.

Rickettsiae: a pathogenic organism thought to be intermediate between bacteria and viruses, because they have features in common with both.

Spirochetes: an order of bacteria containing slender cells 6 to 500µm in length in the form of spirals of at least one complete turn. They are motile, whirl or spin about on their long axis, and are thereby propelled forward or backward. Some forms are parasites; others are free-living or saprophytic.

Vector: an organism (generally an arthropod or a mollusk) that carries and transmits a parasite or pathogen from one vertebrate host to another. A vector is usually an intermediate host of a disease causing organism, and as a carrier is capable of transmitting parasites or pathogens to a definitive or final host. If the parasites or pathogens multiply in the host organism, it is a biological vector; if multiplication or development does not occur, it is a mechanical vector.

Zoonoses: diseases (infections), the agents of which periodically invade the human body and are also common to other animals. In the United States and western Europe, this generally means diseases shared with other vertebrates, especially other mammals. In eastern Europe, it means all animals including invertebrates. Entomologists are concerned with those infections in which arthropods appear in the chain of transmission. Zoonoses involves man becoming the accidental or terminal host when inoculated with a pathogen by an arthropod vector.