Fv

FIGURE 12.35 Section of horse brain (cerebrum) infected with eastern equine encephalomyelitis virus, showing neutrophil invasion around capillary, (Photo by J. D. Patterson.) WEE viruses, immunization has reduced the frequency of horse cases. Venezuelan equine encephalomyelitis (VEE) Complex Encephalomyelitis in equids caused by viruses of the VEE complex occurs in northern South America, Central America, and Mexico. The epizootic viruses are transmitted by many species of mosquitoes (see Table...

Minor Arthropod Problems Of Medicalveterinary Interest

In addition to arthropod groups detailed in the chapters that follow, a few arthropods in other groups may have minor, incidental, or occasional significance to human and animal health. These include springtails (order Collembola), bark lice (order Pscoptera), walking sticks (order Phasmida), mayflies (order Ephemeroptera), earwigs (order Dermaptera), thrips (order Thysanoptera), caddisflies (order Trichoptera), centipedes (class Chilopoda), and millipedes (class Diplopoda). On rare occasions,...

Life History

The basic developmental stages in the life history of mites are the egg, prelarva, larva, protonymph, deutonymph, tritonymph, and adult. Depending on the taxonomic group, one or more stages may be suppressed, resulting in a wide range of life-history patterns (e.g., chiggers Fig. 23.2). Eggs may be deposited externally or may be pigure 23.2 Developmental stages in life cycle of chiggers (Trombiculidae). The protonymph and tritonymph are inactive stages passed within the cuticle of the engorged...

Table

California Serogroup (Bunyavirus, Bunyaviridae) Classification, Mosquito Associations, Vertebrate Hosts, and Geographic Distribution of Virus Types and Subtypes California encephalitis California encephalitis Tahyna Lumbo Melao Jamestown Canyon Ochlerotatus dorsalis Ocblerotatus and Aedes spp. Ochlerotatus triseriatus Ochlerotatus stimulans group Ochlerotatus canadensis Culiseta inornata Aedes, Anopheles, Psorophora Ae. vexans, Cs. annulata Ae. pembaensis Ochlerotatus scapularis Cs. inornata...

Behavior And Ecology

An aspect of fly behavior of particular interest to medical and veterinary entomologists is the host-finding capabilities of blood-feeding species. While various mechanisms have been described, they generally fall into two categories olfactory and visual. A common olfactory cue used by blood-feeding insects, including many true flies, is the relative titer of carbon dioxide (C02) in the atmosphere surrounding, or downwind from, the host. If the goal of a mobile parasite is to locate a...

Veterinary Importance

Under certain conditions, lepidopterous species can cause veterinary problems. These usually involve the ingestion of urticating caterpillars or the caterpillars of nonurticat-ing species, which contain toxins in their body fluids. The result is irritation and inflammation of the lining of the digestive tract, variously called erucic stomatitis, eru-cicgastroenteritis, and erucicgastroenterocolitis. Reactions following ingestion may be immediate or delayed and range from being mild to fatal....

Taxonomy 163 Morphology 164 Life History 165 Behavior And Ecology 167 Public Health Importance 169 Veterinary

Biting midges are minute blood-sucking flies represented by only a few of the many genera in the family Cera-topogonidae. They are commonly known as no-see-ums owing to their small size and the fact that they often go unnoticed despite the discomforting bites which they cause. Another name for this group, especially in the northeastern United States, is punkies. It is derived from a Dutch corruption of the Algonquin Indian root punkwa, which means ashlike, referring to the appearance of the fly...

Info

FIGURE 12,34 Horse dying from infection with eastern equine encephalomyelitis virus in Michigan outbreak in 1980. (Photo by H. D. Newson.) differential diagnosis of horse cases is crucial if these animals are to be used as sentinels for potential transmission of EEE virus to humans. Western equine encephalomyelitis (WEE) virus As with EEE virus, the primary epidemic host of significance for WEE virus is the horse. Human cases are rare. Since the first isolation of WEE virus from the brain of a...

Public Health Importance

Mites can adversely affect human health in many ways. They can infest homes, including carpets, mattresses and bedding, clothing, stored food products, and household pets. Usually they remain unnoticed unless individuals in the household become sensitized and develop various allergies upon subsequent exposure to these mites. Other mites which normally parasitize nonhuman hosts can cause dermatitis in humans when they bite the skin in efforts to feed on blood or other tissues. Most commonly...

References And Further Reading

A. (1958). Venomous moths and butterflies. Journal of the Washington Academy of Science 48, 18-21. Amarant, T., Burkhart, W., LeVine, H., Ill, Arocha-Pinango, C. L., and Parikh, I. (1991). Isolation and complete amino acid sequence of two fibrinolytic proteinases from the toxic Saturnid caterpillar Lonomia achelous. Biochimica et Biophysica Acta 1079, 214-221. Baerg, W. J. (1924). On the life history and the poison apparatus of the white flannel moth, Logon,...

Phlebotominae

Methods for investigating suspected breeding sites of phlebotomine sand flies include the direct examination of soil and litter, extraction by Berlese funnel, wet sieving or flotation, and emergence trapping. Surveillance and collection methods for adult sand flies include trapping and aspiration from resting sites, humans, and bait animals. Effective trap designs include light traps, bait traps, sticky traps, and flight traps. Smoke, insect repellent spray, or a twig or stick can be used to...

Table I

Important Muscid Pests of Humans and Domestic Animals in North America Little house fly Latrine fly and relatives H. ijjnava * ( Opbyra leueostoma) Muscina stabulans M. levida ( assimilisc) Fannin canicularis F. scalaris, F. femoralis Haematobia irritans irritans Musca autumnalis Hydrotaea meteorica, H. scambus, and others Species introduced to North America from the Old World others are cosmopolitan or native to the New World. b According to Huckett and Vockeroth (1987). 'According to Skidmore...

Table Ii

Disease Agents Transmitted by Black Flies Filarial nematodes Dirofilaria ursi Mansonella ozzardi O. ochengi O. ramachandrini O. possibly skrjabini S. aureum complex, S. Vernum group P. decemarticulatum, C. ornithophilia, S. aureum complex, S. Vernum group P. decemarticulatum, C. ornithophilia, S. anatinum, S. aureum complex, S. euryadminiculum, S. venustum complex, S. Vernum group S. aureum complex, S. vernum group Simulium spp., especially S. adersi P. decemarticulatum, S. aureum complex S....

Rickettsialpox

The only other mite reported as a possible vector of R. ctkari is Ornithonyssus bacoti, based on experimental transmission studies using laboratory white mice Lackman, 1963 Philip and Hughes, 1948). Tsutsugamushi disease is a mite-borne rickettsiosis of humans that is endemic in eastern and southern Asia, the western Pacific region, along the northern coast of Australia (Queensland and Northern Territory), and the Indian subcontinent. Cases may occur as far west as Afghanistan, Pakistan, and...

Bartonellosis

Bartonellosis is a disease of humans caused by a hemo-trophic bacterium, Bartonella bacilliformis (Fig. 9.4), transmitted by sand flies. It occurs sporadically and in epidemics at 500-3000 m in the Andes mountain valleys of Peru, Ecuador, and Colombia and at low elevations in the coastal provinces of Ecuador. B. bacilliformis is a small, motile, aerobic, gram-negative coccobacillus which attaches to red blood cells and invades the endothelial cells of the human host. KT LtVr Vii-' r I' J HI V'...

Fear Of Arthropods

Some people detest arthropods, or infestation by them, to such a degree that they suffer from entomophobia, the fear of insects arachnophobia, the fear of spiders and other arachnids or acarophobia, the fear of mites (including ticks). Showing concern or disapproval towards the presence of potentially injurious arthropods is probably a prudent and healthy reaction, but phobic behaviors reflect an unusually severe psychological response. Such persons exhibit more-than-normal fear when they...

Forensic Entomology

Forensic entomology is the study of arthropods, especially insects, associated with crimes and other aspects of the courts and judicial system. Forensic entomology usually involves the identification of insects and other arthropods associated with human remains as an aid to determining the time and place of death. Time of death can often be ascertained based on the ambient temperature and other weather conditions over the preceding days at the crime site and by correlating this information with...

Taxonomy

The Hippoboscidae, Streblidae, and Nycteribiidae represent three families of the superfamily Hippoboscoidea (order Diptera, suborder Cyclorrhapha), although some authors consider these families to be subfamilies of the Hippoboscidae. Because of similarities in mechanisms of feeding and reproduction as well as specialized morphological characteristics, the Hippoboscidae, Strebl-idae, and Nycteribiidae have been considered by some to be monophyletic and are included in the group Pupipara...

Ants

Ants are ubiquitous, occurring throughout most of the world, including most oceanic islands. The only places that they do not exist is above the tree line in mountainous areas and in the Antarctic. Most groups of ants have species that occur worldwide. However, some groups and subgroups are restricted to specific areas the acacia ants (pseudomyrmecines) and ponerines, for example, occur primarily in the tropics, and bull-dog ants are found only in Australia. The primarily tropical army ants...

Morphology

The most striking feature of cimicids is their dorso-ventral flattening. Adults of the oval, mahogany-colored Cimex species generally range in length from about 5.5 to 7.0 mm, with abdomens 2.5 to 3.0 mm wide (Fig, 5,13). The females are larger than the males. The bat bug L. boueti differs from C. lectularius and C. hemipterus in having a very narrow pronotum, only slightly wider than the head, and very long legs. It is a smaller species, the FIGURE 5.13 Human bed bug (Cimex kctularius) adults....

Syrphidae Flower Flies Hover Flies

FIGURE 8.19 Chloropidae, eye gnat Liohippdatespusio). (A) Adult female (B) larva. (From Herms, 1939.) FIGURE 8.19 Chloropidae, eye gnat Liohippdatespusio). (A) Adult female (B) larva. (From Herms, 1939.) on stems, roots, and root hairs of grasses. The frit fly (iOscinella frit) and the wheat stem maggot (Meromyza americana) are important agronomic pests of grain crops. Other species are saprophytes, feeding mostly on decaying vegetable matter in soils, while a few are predators or gall formers....

Human Lice as Intermediate Hosts of Tapeworms

Occasionally humans become infested with the pored tapeworm (Dipylidium caninum). Although carnivores are the normal definitive hosts for this parasite, humans can be infested if they accidentally ingest dog biting lice (T. canis), which serve as intermediate hosts. Although this would appear to be an unlikely event, infants, especially babies playing on carpets or other areas frequented by a family dog, may touch an infested louse with sticky fingers which may then be put into their mouth,...

Surveillance

The number of cases of most vector-borne diseases typically varies over both time and space. Information on the number of cases can be gathered from morbidity and mortality records maintained by state or national governmental agencies for the human population. Morbidity data are records of illness, whereas mortality data are records of the cause of death. These data vary greatly in their quality and timeliness, depending upon the accuracy of determining the cause of illness or death and the...

Solitary Bees

Most bees are solitary or, at most, communal or semiso-cial. Some species of the family Halictidae, which include the sweat bees, are in fact true social bees. A few of the solitary communal and social species form dense nesting aggregations, usually in soil, where they excavate cells in which to rear their larvae. Larvae of all bee species feed on pollen and nectar provisioned in these cells. Nesting activity is quite variable, ranging from a single nest to FIGURE 19.27 Head of German shepherd...

Fleas Of Medicalveterinary Importance

Human flea (Pulex irritans) This flea will feed on humans and is capable of transmitting pathogens of medical importance. However, it is more commonly an ectoparasite of swine and domestic cats and dogs in most parts of the world. Although P. irritans is currently an infrequent parasite of humans in developed countries, this has not always been the case. P. irritans has a patchy but cosmopolitan distribution and often occurs in remote and isolated areas. Adults of this species lack both genal...

Lice Of Livestock

Although louse populations of a few hundred individuals commonly occur on healthy livestock, sometimes these numbers can reach into the thousands or, rarely, to more than a million per animal. It is under the latter conditions that detrimental effects to the host occur. These include restlessness, pruritus, anemia, low weight gain, low milk yield, dermatitis, hide or fleece damage, skin crusting or scabbing, and lameness. Large louse populations on domestic stock typically develop on juvenile,...

Human Scabies

Or crusted lesions, usually on the hands and feet. Pruritus is typically mild or absent altogether, despite the extremely large numbers of mites, sometimes in the thousands, amidst the overgrowth of keratin tissue in the horny layer of the epidermis. The lack of discomfort and absence of burrows often results in these cases going undiagnosed. This condition is highly contagious and can be spread even on casual contact due to the large numbers of mites involved. Victims thus can serve as silent...

And Skin Piercing Moths

The only lepidopterans known to be capable of piercing animal skin are members of the noctuid genus Ca-lyptra in Southeast Asia. Like many geometrids and other zoophilous moths, they tend to be attracted to wounds, open sores, cuts, scratches, scabs, and other skin lesions (Figs. 18.20, 18.21). However, while these other moths imbibe only exposed wound fluids, Calyptra spp. are capable of piercing the underlying tissue to draw fresh blood. Only the males are hematophagous. Females are believed...

Interseasonal Maintenance

That do not play a substantial role in either enzootic maintenance or epidemic transmission. Vector incrimination combines field and laboratory data that measure field infection rates, vector competence, and vectorial capacity. Infection rates. The collection of infected arthropods in nature is an important first step in identifying potential vectors, because it indicates that the candidate species feeds on vertebrate hosts carrying the parasite. Infection data may be expressed as a percentage...

Fanniidae Fanild Flies

Four species of Fannin have been reported to cause myiasis little housefly (F. ecmicularis), latrinefly (F. scalaris), F. incisumta, and F. manicata. Adults of these flies look like small, slender house flies. They are drab gray in color and lack black stripes on the thorax. The larvae commonly occur in feces, on rotting fruits or bulbs, and in bird nests. Larvae occasionally occur in older, somewhat dried carrion. The larvae have a characteristic, fringed appearance (Fig. 16.8) that easily...

What Is The Morphology Of Black Flies

Horn Fly Sting

The life stages of a typical muscid fly consist of egg, larva, pupa, and adult (Fig. 14.1). Eggs are similar to those of closely related families. They may occur singly or in groups. They are generally creamy in color, 0.8-2.0 mm long, elongate ovate in shape, and concave dorsally where two ribs form hatching pleats (Fig. 14.2). Larvae of muscid flies and related families are known as maggots, and there are three instars in all species. The body is tapered, with the head and mouth hooks at the...

Lice Of Veterinary Interest

A wide variety of lice infests domestic, livestock, and laboratory animals (Tables I and II). Many hosts, particularly small rodents, often support few if any lice, whereas large hosts such as livestock animals, including poultry, may be parasitized by very large numbers of lice. For example, fewer than 10 mouse lice (Polyplax serrata) on a house mouse are a typical burden, but more than a million lice may be present on extremely heavily infested sheep, cattle, horses, or other large animals.

Fungus Gnats

Darkwinged fungus gnats are 1-11 mm in length and closely resemble the Mycetophilidae except that their eyes meet above the base of the antennae. The adults (Fig. 8.9A) are usually encountered in moist, shady habitats. The larvae (Fig. 8.9B) feed on a wide range of materials, including fungi, decaying plants, manure, and, in some cases, the roots of greenhouse plants, soybeans, and clovers. Lycoriella mali is a major pest of commercial mushrooms, feeding on compost and all stages of mushrooms....

Luridae

This interesting, but small, group of scorpions spans three continents. None of them is considered dangerous. There are 6 genera and approximately 21 species. The genera Iu-rus and Calchas, each with 1 species, are closely related, are relatively large, and are found in Turkey and Greece (including Samos, Crete, and other islands). The genera Caraboctonus (1 species) and Hadruroides (9 species) are found in western South America. Caraboctonus is found in Chile and Peru Hadruroides is...

Bed Bugs Cimicidae

The family Cimicidae includes species known by several common names, including bed bugs, bat bugs, and swallow bugs. All species in this family are wingless, obligate hematophagous ectoparasites. Their medical and veterinary importance relates primarily to the loss of blood and discomfort caused by their feeding on vertebrate hosts. The monograph on the Cimicidae by Usinger (1966) is still the most comprehensive and best work on the ecology, morphology, reproductive biology, systematics, and...

Loxoscelism

Loxocelism

The clinical syndrome called loxoscelism is caused by the bite of Loxosceies species known as fiddle-back, brown recluse, or violin spiders. It is also called necrotic arach-nidism because of cytolytic components of the venom which cause necrosis of tissues around the bite wound. The common names of these spiders refer to a usually distinct fiddle- or violin-shaped marking on the dorsum of the cephalothorax, the neck of which is directed posteriorly. The base of the violin encompasses the eyes...

Storage Mites

People who handle mite-infested stored products may become sensitized to the mites on subsequent contact, resulting in an immunological response called storage-mite allergy. Although the precise nature of the allergens is unknown, these substances include components of both live and dead mites and material produced in the mite alimentary tract. Sensitized persons may experience either contact dermatitis or respiratory allergy, depending on the type of exposure. Allergic contact dermatitits...

Prevention And Control

There are three major approaches for controlling myiasis avoiding contact between potential hosts and myiasis-causing flies early treatment of wounds to prevent myiasis and reduction or elimination of myiasis fly populations. In the area of human health, there is general reliance on hygiene and medical or surgical intervention. In veterinary cases the most common approach is the use of insecticides, especially systemic compounds, administered to the host. Preventing unnecessary or avoidable...

Skin Invading Mites

Dog Demodex Life Cycle

Representatives of only two families of mites typically invade human skin or associated dermal structures and glands. They are the Demodicidae, or follicle mites, and the Sarcoptidae, or scabies mites. Whereas only a relatively small number of humans infested with follicle mites develop clinical problems, most individuals who become infested with the human scabies mite experience an annoying, often severe, dermatitis. Members of this family are called follicle mites. They are extremely tiny,...

Chaoboridae Phantom Midges

Lake Entomology

Adults are small (1.4 10 mm in length), mosquito-like midges without the elongate proboscis and abundant wing scales characteristic of the Culicidae (Fig. 8.1 OA). Eggs of members of the common genus Corethrella are laid on the surface of water and hatch within 2 4 days. The larval stage averages 15 32 days, and the pupa is active and lasts 3 6 days. The transparent larvae (Fig. 8.1 OB) are aquatic and are found commonly in lentic habitats (e.g., large lakes, small pools, bogs, small ponds)....

Sarcophagidae Flesh Flies

Flesh Fly Family Sarcophagidae

FIGURE 16.16 Red-tailed flesh fly, Sarcophaga hemorrhoidalis (Sar-cophagidae), adult. (From Greenberg, 1971.) FIGURE 16.16 Red-tailed flesh fly, Sarcophaga hemorrhoidalis (Sar-cophagidae), adult. (From Greenberg, 1971.) larviparous the gravid female retains the eggs in an expanded, bilobed, uterine pouch until they are ready to hatch. Females produce 30-200 larvae, depending on the species involved. Flesh fly larvae (Fig. 16.17 are more robust than blow fly larvae and possess paired mandibles...

Contributors

Numbers in parentheses indicate the pages on which the authors' Peter H. Adler (185), Department of Entomology, Clemson University, Clemson, South Carolina 29634-0365, USA Roger D. Akre (383), Deceased, formerly Department of Entomology, Washington State University, Pullman, Washington 99164-6382, USA Richard J. Brenner (29), USDA-ARS, Office of Technology Transfer, Beltsville, Maryland 20705 formerly USDA-ARS, Center for Medical, Agricultural and Veterinary Entomology, Gainesville, Florida...

Name The Subfamilies Of Blackflies

Subfamilies, Common Names, and Distribution of Ants (Formicidae) Based on Holldobler and Wilson (1990) Omitted are the rare subfamilies Nothomyrmeciinae, Leptanillinae, and Aneuretinae Harvester ants, leaf cutting ants, fire ants, pavement ants, pharaoh ants, others Thatching ants, carpenter ants, weaver ants, others Subfamilies, Species, Common Names, and Principle Nest Sites of Selected Vespid Wasps in North America Subfamilies, Species, Common Names, and Principle Nest Sites of Selected...

Internal Acariasis

With human dermatitis and other skin disorders (Hewitt et al., 1973 Krantz, 1978 Oehlschlaegel et al., 1983) and to invade various organs and body fluids of humans and other animals (Dahl, 1910). The most commonly implicated species is Tarsonemus bominis. It is generally believed that these reports represent contamination of glass slides and other materials used in preparation of tissues for microscopic examinations (Hewitt et al., 1973 Samsin k etal, 1976). Excluding tick-borne diseases, there...

House Dust Mites

Euroglyphus Maynei

A major source of human allergens in the home is house dust and its associated mite fauna. Where humidity is sufficiently high, fungi tend to thrive in accumulated dust, providing food for a variety of house-infesting mites that are primarily saprophages or fiingivores. Many of these mites are the same species that infest stored products, nests of rodents and birds, and animal litter. When their populations reach high levels in the home, they can cause acute or chronic allergic reactions...

Ischnuridae

Formerly considered a subfamily of the Scorpionidae, the ischnurids are now regarded as a separate family. They range in size from small to very large and typically have a flattened body shape. The claws are massive in comparison to the body, but the metasoma is unusually thin and feeble-looking. Sometimes the metasoma is so short that it cannot reach to the front of the animal. Although capable of burrowing, most of these species are associated with crevice habitats in rocky areas, on trees,...

Vesicular Stomatitis

Three serotypes of vesicular stomatitis virus (Rhabdoviri-dae Vesiculovirus) that cause febrile disease in humans are believed to be transmitted by sand flies. The Alagoas, Indiana, and New Jersey serotypes axe widely distributed in tropical and temperate areas of North and South America and have been repeatedly isolated from L. shannoni, L. trapidoi, L. ylephiletor, and unidentified sand flies. L. shannoni is a proven vector of the New Jersey serotype among feral pigs on Ossabaw Island, GA....

Tungiasis

Tungiasis is the pathological condition resulting from infestation by fleas belonging to the genus Tunga. Although there are several species of Tunga, only the chigoe (T. penetrans) attacks humans. T. penetrans occurs in many tropical and subtropical zones but is especially common in the New World tropics, the West Indies, tropical Africa, and southern India. The first record of this flea was in 1492 from crewmen of Christopher Columbus stationed in Haiti. It apparently spread from the New...

Human Notoedric Mange

Humans occasionally become infested with Notoedres cati, a sarcoptid mite that causes notoedric mange in cats. Cases in humans are called human notoedric mange or human notoedric scabies. Following prolonged exposure to infested cats, people may become sensitized to this mite and develop intense pruritus within a few hours of subsequent contact with them. The reaction is induced without the mites actually burrowing. The most common sites of skin lesions are on the hands and legs, reflecting the...

Medical And Veterinary Entomology

Copyright 2002, Elsevier Science (USA). All rights reserved. 147 FIGURE 9.1 Moth fly (Psychoda sp.), adult female. (From McCafferty, 1981.) FIGURE 9.1 Moth fly (Psychoda sp.), adult female. (From McCafferty, 1981.) when at rest. The mandibles are rudimentary or absent. Two genera, Psychoda and Telmatoscopus, include species of public health and veterinary importance. Both genera are widely distributed throughout the world. About 80 species occur in North America. Quate and Vockeroth (1981) have...

Fleas as Intermediate Hosts of Helminths

Transmission of mature larvae by these fleas occurs by bite. Dogs, jackals, and hyenas are the principal definitive hosts of A. reconditum. Several other species of helminths have been isolated from wild-caught fleas, and fleas have been found to serve as suitable intermediate hosts under laboratory conditions. However, the importance of fleas in maintaining these pathogens in nature is unknown. For example, the trichina worm ( Trichinclla spiralis) has been found encysted in the...

Scarabaeidae Scarab Beetles

In some tropical regions where human and animal excrement are abundant in the vicinity of dwellings, scarab beetles living in the dung are sometimes accidentally ingested by young children. These beedes appear in the newly passed stools of children and may disperse from the excrement in a noisy fashion that has been described in Sri Lanka as beetle marasmus (kurumini mandama). Although some of these beetles may infest the fecal matter as it is passed or after it reaches the ground, it is quite...

Oedemekidae False Blister Beetles

C. mdanoccphalus, and C. picticollis, A Lytta species in China also has been associated with human dermatitis (Table II). Blister beetles are found most often on flowers or foliage, where the beetles feed on pollen and other plant tissues. Epicauta species are usually abundant where grasshoppers flourish because the larvae of these meioids feed on grasshopper eggs. Most people who develop blister beede lesions are agricultural workers or soldiers on maneuvers in areas where the beetles are...

Transmission Cycles

Transmission cycles vary considerably depending upon their complexity and the role of humans as hosts for the parasite. A vector-borne anthroponosis is a disease resulting from a parasite that normally infects only humans and one or more anthropophagic vectors Fig. 2.1 . Malaria, some forms of filariasis, and louse-borne typhus are examples of anthroponoses with transmission cycles that involve humans and host-specific vectors. Humans serve as reservoir hosts for these parasites, which may...

Stored Products Mites

The dermatitis experienced by food handlers on contact with A. siro is commonly known as grocer's itch. Other names for dermatitis caused by A. siro and related mites are baker's itch, dried-fruit-mite dermatitis Carpo-glyphus lactis, Carpoglyphidae Fig. 23.13 , wheat pollard itch Suidasia nesbitti family Suidasiidae , and vanillism, reflecting the product or commodity involved. A mite closely related to A. siro that also causes human dermatitis is A.farris Fig. 23.14 . It is a...

Syrphidae Flower Flies Hover Flies Rat Tailed Maggots

This is a large family 180 genera, 6000 species that includes only a few taxa that cause gastrointestinal myiasis. Adults also are called drone flies because of their beelike appearance and resemblance to honeybee drones. The terms flower flies and hover flies refer to their common habit of visiting flowers for nectar and pollen and their ability to hover motionless in flight, The larvae of Eristalis Fig. 16.4 and other aquatic genera are called rat-tailed maggots, referring to the long,...

Other Flea Borne Pathogens and Parasites

Many of the flea-borne pathogens listed in Table II cause diseases in humans, with wild or domestic animals serving as reservoirs. These include plague, tularemia, murine typhus, Q fever, and sylvatic epidemic typhus. Infections of domestic animals with most of these pathogens can be nonapparent, febrile, or fatal, depending on the host species, its health, and the strain of pathogen involved. Cats, for example, are typically susceptible to most strains of plague, whereas dogs usually are not....

Nose Bot Flies Oestrinae

FIGURE 16.38 Common horse bot fly, Gasteropbilus intestinalis Oestridae, Gasterophilinae , adult female. A Dorsal view B lateral view. From lames, 1947. FIGURE 16.38 Common horse bot fly, Gasteropbilus intestinalis Oestridae, Gasterophilinae , adult female. A Dorsal view B lateral view. From lames, 1947. distantly related mammalian groups. Eggs which are ingested with forage or wetted by self-grooming of the front legs hatch after a brief incubation. Eggs located on the host's head hatch...

Urticating Caterpillars

The three most important lepidopteran families with stinging caterpillars are Limacodidae, Megalopygidae, and Saturniidae. Other families include Lymantriidae, Arctiidae, Lasiocampidae, Noctuidae, Thaumetopeidae, Nymphalidae, and Morphoidae. With the exception of the last two families, all are moths as aduits, Members of this family are called flannel moths, referring to the densely hairy adults and larvae. They occur in the Palearctic and Nearctic regions, but especially in South America and...

New World Skin Bot Flies Cuterebrinae

Infested Botfly Human

FIGURE 16.19 Cotton mouse, Peromyscusgossypinus, with mature rodent bot, Cuterebra sp., or wolf posterior end of bot, with posterior spiracles exposed, projecting from location at base of host tail. Photo by G. R. Mullen. FIGURE 16.19 Cotton mouse, Peromyscusgossypinus, with mature rodent bot, Cuterebra sp., or wolf posterior end of bot, with posterior spiracles exposed, projecting from location at base of host tail. Photo by G. R. Mullen. normal hosts are rodents e.g., Microtus, Neotoma, and...

Calliphoridae Blow Flies Carrion Flies Floor Maggots Nest Maggots and Screwworms

2nd Instar Blow Fly

The most generalized of the six families of Oestroidea is the Calliphoridae, with over 1000 species. Among the members of this large family there is a transition from the facultative myiasis habit by a large number of normally saprophagous species to obligatory myiasis by a relatively small number of species ca. 100 . The larvae typically feed on wet living or dead flesh. Desiccation is detrimental to both egg and larval survival. The following discussion treats the more important, widely...

Species Of Medical Veterinary Importance

Maxillary Palp Fannia Scalaris

Adults and larvae of some important muscid flies can be identified tentatively from external characteristics and from features of their behavior, habitat, and geographic location. This nonbiting filth fly occurs on all continents except Antarctica. It is native to the Afrotropical and Oriental regions and was probably introduced into the Americas by Europeans during colonial times. Adults are gray and black flies, 6 9 mm long, with four black vittae on an otherwise gray thorax Figs. 14.1 and...

Elassoctenus Harpax Of Austraila Medical Importance

Approximately 3,000 genera and 36,000 species of spiders have been described worldwide. In North America alone there are 64 families, some 500 genera, and 3,400 species Coddington et al., 1990 . Among the more than 100 families of spiders, about 20 families include species that reportedly cause medical concerns when they bite humans and other animals. The 5 most important families are the Dipluridae, Hexathelidae, Theraphosidae, Sicari-idae Loxoscelidae , and Theridiidae. See Bettini and...

Table Viii

Anopheles Vectors of Human Malaria Parasites in 12 Epidemiologic Zones Subgenera, Species, and Geographic Distributions are Given Subgenus Anopheles freeborni, punctipennis, quadrimaculatus Subgenus Nyssorhynchus albimanus Subgenus Anopheles azteeus, pseudopunctipennis, punctimacula, Subgenus Nyssorhynchus albimanus, albitarsis, allopha, aquasalis, argyritarsis, darlingi Subgenus Anopheles pseudopunctipennis, punctimacula Subgenus Nyssorhynchus albimanus, albitarsis, aquasalis, argyritarsis,...

Anal Cills

Ochlerotatus Detritus

FIGURE 12.3 External anatomy of mosquito larvae, dorsal view, with anal segment and siphon at posterior end rotated to provide better view. A Anopheline form Anopheles maculipennis -y B culicine form Aedes cinerms . From Marshall, 1938. FIGURE 12.4 Heads of mosquito larvae, postero-ventral view. A Anopheline form Anopheles quadrim amp 'C la'tus B culicine form Ochlerotatus ftdvuspollens C toxorhynchitine form Toxorhynchites hrevipalpis . The lateral palatal brushes of most larvae are used to...

Muscidae Dung Flies

The large family Muscidae includes at least seven genera in which species cause myiasis Table I . Muscid larvae Fig. 16.9 develop in a wide diversity of decaying organic matter, usually of plant or fecal origin. Occasionally they develop in old or buried carrion that is unsuitable for blow-fly exploitation. All stages of myiasis-causing muscids are typically house fly-like in appearance. Exceptions are Neomyia and Hydrotaea species, in which some adults have metallic coloration similar to blow...

Equine Allergic Dermatitis

Horses exposed to bites of certain Culicoides species commonly exhibit an allergic skin reaction. This typically occurs as a seasonal dermatitis affecting the withers, mane, tail, and ears. The back, ventral midline, and other body regions also can be affected, presumably reflecting the feeding sites of different biting midges involved. Equine allergic dermatitis was first attributed to Culicoides bites in Australia in the early 1950s, where it was known as Queensland itch. It is now known to...

Image Of The Sensilium In Flies

Flea Image Morphology

FIGURE 7.1 Morphology of generalized adult flea, female. T, abdominal tergites St, abdominal sternites. From Lewis, 1993b. FIGURE 7.1 Morphology of generalized adult flea, female. T, abdominal tergites St, abdominal sternites. From Lewis, 1993b. FIGURE 7.2 Morphology of the head and prothorax of representative adult fleas of medical and veterinary importance. A Cat flea Ctenocephalidesfills -, B Dog flea C. cants C Human flea Pulex irritans D Northern rat flea Nosopsyllusfasciatus E Oropsylla...

Common Species Of Hippoboscids

Sheep Ked Drawing

A number of louse flies in the genus Hippobosca are of particular interest to veterinary entomologists. Most FIGURE 17.5 Sheep ked, Melophagus ovinus Hippoboscidae , female, dorsal view. Courtesy of Cornell University Agricultural Experiment Station. FIGURE 17.5 Sheep ked, Melophagus ovinus Hippoboscidae , female, dorsal view. Courtesy of Cornell University Agricultural Experiment Station. occur in Europe, Africa, and Asia. Occasional introductions have been made into the United States with the...

Pictures Of Simulium Swarming Around The Head

Filarial Nematode

Species of Black Flies Regarded as Significant Biting and Nuisance Pesrs of Humans, Livestock, and Poultry Austrosimulium unjjulutum Prosimttliutn tnixtum group Simulium amazonieum complex S. arakawae S. boncterense S. buissoni S. chohdkovskii S. decimatum S. jenningsi S. parnassum S. penobscotsnse S. posticatum S. quadrivittatum S. sanguineum S. tescorum S. venustum complex Livestock A, pestilens Cnephia pecuarum S. arcticum complex S. chohdkovskii S. chutteri . decimatum S. equinum S....

Epizootic Hemorrhagic Disease

FIGURE 10.12 White -tailed deer fawn infected with epizootic hemorrhagic disease virus. Note hanging head and protruding tongue. Photo by G. R. Mullen. FIGURE 10.12 White -tailed deer fawn infected with epizootic hemorrhagic disease virus. Note hanging head and protruding tongue. Photo by G. R. Mullen. referred to as black tongue disease by deer hunters in the southeastern United States. Clinical disease in white-tailed deer and other ruminants varies from sudden death without apparent signs of...

References And Further Reading 426

Solpugids are usually yellow or brownish in color and rather hairy. The body length varies from 1 to 7 cm, with the largest species having a leg span up to 12 cm. The prosoma and opisthosoma are broadly joined, with the latter being visibly segmented Fig. 21.1 . The most prominent structures are the greatly enlarged, powerful pair of chelicerae which are used to seize, crush, and tear apart food. With the exception of Rhagodes nigrocinctus in India, solpugids are generally believed to lack...

Mite Induced Dermatitis

Chicken Mite

From Strandtmann and Wharton, 1958. ventral view. From Strandtmann and Wharton, 1958. to their bat hosts, Chiroptonyssus robustipes has been known to cause the death of heavily infested, captive Brazilian free-tailed bats Tadarida brasiliensis . This mite attaches primarily to the wings, where its feeding can result in increased vascularity and edema at the bite sites, enlargement of lymphatic vessels, hyperkeratosis, and excoriation of the stratum corneum Sweatman, 1971 . A few...

Screwworm Eradication Program

It was not until 1954-1955, however, that the first successful field test was achieved with the eradication of the primary screwworm Cochliomyia hominivorax on the island of Curacao Netherlands Antilles . This entailed the mass production of sterile males from gamma-irradiated pupae which were then released to mate with wild females. Eggs resulting from these matings do not hatch, thereby reducing fly populations. Subsequent successes in eradicating C. hominivorax were achieved in the...

Gary R Mullen Lactrodectism

The term latrodectism, also known as neuromyopathic animism, is a syndrome caused by the bite of any of several Latrodectus species. The venom of these spiders contains potent neurotoxins which cause generalized pain, nausea, vomiting, faintness, dizziness, perspiration, and neuromuscular involvement in the form of muscle weakness, stiffness, cramps, tremors, incoordination, numbness or prickling sensations, paralysis, disturbed speech, and difficulty breathing. The main toxic fraction of the...

Intermediate Hosts of Parasites

Tapeworms cestodes , flukes trematodes , roundworms nematodes , and thorny-headed worms acanthocepha-lans of many species that infest domestic and wild animals use beetles as intermediate hosts. Animals become infested by ingesting parasitized beetles that contaminate feed or bedding tenebrionids, carabids or that are attracted to animal dung scarabaeids , or by ingesting water in which infecdve beetles have disintegrated. Two tapeworms that infest the small intestines of poultry are the...

H

Exflagellating O I microgametocyte O FIGURE 12.30 Life cycle of Plasmodium vivax in human and Anopheles hosts. Modified from Strickland, 1991. cells release saliva into the skin prior to ingesting blood. The period of time between ingestion of gametocytes and infection of the salivary glands with sporozoites is the extrinsic incubation period. In the human host, sporozoites migrate in the blood to the liver within minutes of entering subdermal capillaries. They invade liver parenchymal cells,...

V

FIGURE 11.8 Gametocytes of the protozoan Leucocytozoon simondi in blood cells of a mallard duck. A Round form B elongate form. Photo by E. C. Greiner. Other Parasites and Pathogens of Veterinary Importance Black flies transmit additional parasites to wild animals Table II . The protozoan Trypanosoma confusum is specific to birds in North America and is transmitted when infected fecal droplets from the black fly contaminate the bite. Birds of numerous families serve as hosts. Other species of...

B

A Adult B larva. From McCafferty, 1981. into the anterior thoracic segments Fig. 8.7B . They are found in a wide range of aquatic and semiaquatic habitats and are commonly collected at the margins of streams and ponds and in moist leaf litter, A few species occur in dry soil, where the larvae may be pests of grain and turf crops by feeding on the roots. Most species in temperate areas have one or two generations a year, with four larval instars and a brief pupal...

Description Of Dorsal View Of Fowl

Scapula Fowl

FIGURE 23.4 Chicken mite, Dermcmyssusgnllime Dermanyssidae , female, ventral view. Modified from Gorham, 1991 courtesy of the US Department of Agriculture. and Liponyssoides. They are ectoparasites primarily on wild and domestic rodents and birds. These mites feed on the blood of their hosts by piercing the skin with their long, slender, extrusible chelicerae with highly reduced chelae at their tips. Dermanyssids spend most of their time in the nests of their hosts, crawling onto the animals...

When Do Black Flies Hatch In Ontario Canada

FIGURE 23.10 Larval stage chigger of the harvest mite, Neotrom-bicula mtitmnalis Trombiculidae , of Europe. A Dorsal view B scutum dorsal plate , showing characteristic arrangement of setae. Modified from Baker etal., 1956. birds, and mammals, with humans serving only as accidental hosts. The life history of trombiculid mites includes the following sequence of stages egg, prelarva, larva, proto-nyrnph, deutonymph, tritonymph, and adult Fig. 23.2 . The eggs are typically laid in soil or ground...

Murine Typhus

Murine typhus, also known as endemic typhus or Mexican typhus, is caused by infection with the rickettsial organism Rickettsia typhi formerly R. mooseri . Although this zoonosis is typically maintained in commensal rats by flea transmission, humans occasionally are infected. Murine typhus is one of the most prevalent rickettsial diseases of humans, even though it is underdiagnosed and its importance is generally unappreciated. R. typhi is a small, obligate, intracellular bacterium that can...

Types Of Problems Caused By Arthropods

The invasion of host tissues by fly larvae, called myiasis, is the most widespread form of host invasion by arthropods. Larvae of many myiasis-causing flies move extensively through the host tissues. As they mature, they select characteristic host sites e.g., stomach, throat, nasal passages, or various subdermal sites in which to complete the parasitic phase of their development. Certain mites also invade the skin or associated hair follicles and dermal glands. Others infest nasal passages,...

Modes Of Transmission

The transmission of parasites by vectors may be vertical or horizontal. Vertical transmission is the passage of parasites direcdy to subsequent life stages or generations within vector populations. Horizontal transmission describes the passage of parasites between vector and vertebrate hosts. Three types of vertical transmission are possible within vector populations transstadial, transgenerational, and venereal transmission. Transstadial transmission is the sequential passage of parasites...

Lice Of Cattle

Lice are a major problem in cattle operations worldwide. Domestic cattle are parasitized by six species of lice three species of Haematopinus, one of Linognathus, one of Solenopotes, and one of Bovicola. Domestic Asiatic buffalo are typically parasitized by H. tuberculatus Tables I and II . Females of the cosmopolitan cattle biting louse Bovicola bovis lay an average of 0.7 eggs per day, which hatch 7 10 days later. Each nymphal instar lasts 5 6 days, and adult longevity can be as long as 10...

History Of Medicalveterinary Entomology

Problems caused by biting and annoying arthropods and the pathogens they transmit have been the subject of writers since antiquity Service 1978 . Homer mid-8th century BC , Aristophanes ca. 448-380 BC , Aristotle 384-322 BC , Plautus ca. 254-184 BC , Columella 5 BC to AD 65 , and Pliny AD 23-79 all wrote about the nuisance caused by flies, mosquitoes, lice, and or bedbugs. However, the study of modern medical-veterinary entomology is usually recognized as beginning in the late 19th century,...