Specimens can then be mounted in a variety of mounting media, such as balsam, Permount, or isobutyl methacrylate (20). However, the frequency of submission is likely to vary with geographic region and the population that is served. at the University of Arizona. 5). (class Arachnida). The following key will aid in the identification of C. lectularius and related cimicids (67). Humans (especially children) are infected with these cestodes upon incidental ingestion of infected fleas (12). The fifth edition of Physician's Guide to Arthropods of Medical Importance has been thoroughly updated to ensure authoritative coverage of this complex and fast-moving discipline of arthropodborne diseases, and serves as a reliable reference covering all of the major aspects of entomology. 8C). Wound myiasis may be caused by fly larvae that are obligatory, facultative, or incidental parasites. If further identification is required that is beyond the comfort level and expertise of the laboratorian, it is recommended that the specimen be sent to a state-level (or other public health) entomologist, a local extension service, or a local university or museum with an active entomology program and reference collection. In all cases of dermal and subdermal myiasis, it is important to remove the entire larva from the boil. Needless to say, the field of medical and public health entomology is vast and covers a variety of disciplines, including, but not limited to, vector control, population genetics, ecology, taxonomy, morphology, and ecology. All stages of ticks may be submitted to the diagnostic laboratory, and in the United States, submitted ticks typically belong to the genera Amblyomma, Dermacentor, Ixodes, and Rhipicephalus. The developing larva forms a boil-like tumor (often referred to as a furuncle), which opens externally to allow the larva to breathe via its posterior spiracles. Alternatively, mites can be mounted with permanent media (see Specimen Collection and Transport, above). Human case of Rickettsia felis infection, Taiwan, Yersinia pestisetiologic agent of plague, The fleas Ctenocephalides felis felis (Bouche, 1833), Ctenocephalides canis (Curtis, 1826), and the mite Cheyletiella (Canestrini, 1886) in the dog and cat: their transmissibility to humans, Zoonotic parasitoses, clinical and experimental studies. Follicle mites in the genus Demodex are commensal mites that live in the hair follicles and sebaceous glands of humans. The heightened awareness in recent years due to a worldwide resurgence of infestations (3) necessitates that diagnostic technologists and microbiologists learn to recognize these bugs or be able to rule them out. What do we know about disease ecology to prevent Lyme disease in the northeastern United States. Accessibility There are three families of ticks, only two of which (Ixodidae, the hard ticks, and Argasidae, the soft ticks) are of public health importance. s. These are bilaterally symmetrical invertebrate animals o with segmented bodies o Jointed appendages o Hard outer coverings or exoskeletons. Nosocomial cases are not common but do occur (95, 96). 2 Fasc. It is not the intention in this chapter to describe in detail the numerous collecting methods used by specialists, but to provide simple guidelines so that the non-specialist can collect medically important arthropods and forward them to medical entomologists and other specialists for identification. Subphylum Chelicerata. Tunga eggs may be collected into liquid medium such as ethanol and submitted to the laboratory for identification. The northern rat flea (Nosopsyllus fasciatus) also transmits plague and murine typhus, although it is not as an aggressive feeder of humans (77). The possibility of intestinal myiasis in man. 2012. The focus is on the morphological identification and proper handling and reporting of cases involving arthropod ectoparasites, particularly those encountered in the United States. 2013 BMA Medical Book Awards Winner As the importance of medical entomology increases, access to up-to-date, authoritative information also becomes increasingly critical. Legac-Wiens PRS, Dookeran R, Skinner S, Leicht R, Colwell DD, Galloway TD. Whether a patient's household has cats or dogs is not significant in the identification of the fleas submitted, as both species readily feed on both hosts, although C. canis is less commonly encountered, and most fleas, even on dogs, are actually C. felis (86). BT, button; PE, peritreme; SL, spiracular slit. Life history with notes on prepupation mortality and pupation habits. disease vectors . An alternative method in this setting is to apply a pyrethrum-based insecticide directly to the tick to rapidly kill and facilitate spontaneous detachment. (Panels A to H are courtesy of the Parasite and Disease Image Library [PaDIL], Melbourne, Australia, published under a Creative Commons license; panel I courtesy of the CDC-DPDx.). Two human cases infected by the horsehair worm, Parachordodes sp. Human ophthalmomyiasis interna caused by Hypoderma tarandi, northern Canada. Contemporary information is a critical element of primary healthcare, but specific therapy has yet to be recommended for most arthropodborne diseases. 2A and andB)B) is a vector of Ehrlichia chaffeensis and Ehrlichia ewingii (ehrlichiosis), Francisella tularensis (tularemia), and (rarely) Rickettsia rickettsii (Rocky Mountain spotted fever [RMSF]) (2, 23, 33). (F) C. hemipterus (head and pronotum) (arrow shows the degree of concavity with the anterior margin of the pronotum). Climate change and range expansion of the Asian tiger mosquito (Aedes albopictus) in northeastern USA: implications for public health practitioners, Regulatory action criteria for filth and other extraneous materials. Arthropodswith medical importance and their role in infectious pathology and tropical diseases. In general, lice are a rare or occasional submission to diagnostic laboratories and are more likely to be head lice rather than pubic or body lice, based on the epidemiology of these arthropods in the United States. You will be subject to the destination website's privacy policy when you follow the link. The effects of preservatives and temperatures on arachnid DNA. 2011. are morphologically similar to Amblyomma spp. Evaluation of specimen preservatives for DNA analysis of bees, Ticks feeding on humans: a review of records of human-biting Ixodoidea with special reference to pathogen transmission, Pictorial key to the adults of hard ticks, family Ixodidae (Ixodida: Ixodoidea) east of the Mississippi River, Auburn University Agricultural Experimental Station bulletin no 426, Evaluation of five popular methods of tick removal, The insects and arachnids of Canada. (C) P. pubis (egg). Ser. Still, the relative importance of medical and public health entomology seems to be increasing (2), with a worldwide resurgence of certain arthropods (e.g., bed bugs) (3) and expanding ranges of others (e.g., mosquitoes and ticks) (4,8). (B) Lucilia sp. 3C), spiny rat mite (Laelaps echidnina), and chicken mite (Dermanyssus gallinae) (2, 65). sharing sensitive information, make sure youre on a federal Amblyomma species in North America are readily identified by the presence of eyes and festoons, an ornate dorsal shield, and palps that are longer than the basis capituli. There are two primary species of bud bugs that infest humans, Cimex lectularius (distributed worldwide) and Cimex hemipterus (distributed primarily in the tropics and subtropics) (2). As such, it is an excellent resource for clinicians, public health workers, and the public. Slits of posterior spiracles sinuoussee step 9. 1 Lecture: Medical Significance of Phylum Arthropoda 1. Prolonged cases that have been known to last for months or years are probably due to repeated ingestion of food contaminated with fly eggs (104). Phormia has been reported to cause ophthalmomyiasis in hospitalized patients (100). Arthropods of Medical Importance | PDF 115 views Arthropods of Medical Importance Uploaded by Renz L. Salumbre Description: Introduction to Medical and Veterinary Entomology Copyright: Attribution Non-Commercial (BY-NC) Available Formats Download as PDF, TXT or read online from Scribd Flag for inappropriate content Download now of 5 Parasitology Arthropods comprise a diverse group of invertebrate animals, united in a common body theme (bauplan) of a jointed, chitinous exoskeleton. 11D, black arrow) (121). Identification is best left to trained entomologists or other specialists. Yoon K-C, Park H-Y, Seo M-S, Park Y-G. The public health importance of these organisms is briefly discussed. While typically not vectors of disease-causing organisms, C. felis is a vector of Bartonella henselae, the causative agent of cat scratch disease (82), and Rickettsia felis (83, 84). Dr. Pritt has presented and published on many topics, including laboratory quality indicators and laboratory detection of infectious diseases. Likewise, cases of envenomation or stings are usually handled by first responders and local poison control and not necessarily submitted to the diagnostic laboratories. Mechanical treatment of phthiriasis palpebrarum. February 2012. (A) Dermatobia hominis (third instar). In Southeast Asia, Leptotrombidium akamushi is an important vector of the rickettsial organism Orientia tsutsugamushi, the causative agent of scrub typhus (tsutsugamushi) (2, 65). 1989. In cases of wound myiasis diagnosed in the United States, it is very important to identify or rule out C. hominovorax, as this species was officially eradicated from the United States in the 1960s (97), and any evidence of local acquisition should be reported to state health facilities or the Centers for Disease Control and Prevention (CDC). Cianferoni A, Schneider L, Schantz PM, Brown D, Fox LM. (D) C. felis (closeup of head). Other arthropods may also be nuisance pests and cause similar dermatologic manifestations by incidental contact (e.g., millipedes, stinging caterpillars, and blister beetles) (13,15), biting and stinging (e.g., horse and deer flies, biting midges, bed bugs, avian mites, and ants), or respiratory problems from inhalation (cockroaches and dust mites and their feces). 13;191 pp. The ticks of Venezuela (Acarina: Ixodoidea) with a key to the species of Amblyomma in the Western Hemisphere, African Ixodoidea. Booklice feed on a variety of organic materials, including molds, cereals, pollen, dead insects, and glue used in the bindings of books (19, 131) and may be nuisance pests indoors. Paragordius varius (Leidy) (Nematomorpha) infection in man: a case report from Quebec (Canada). Occasionally, wound myiasis can be quite severe, possibly even fatal, if the colonizing agent is also capable of attacking living, healthy tissue. All fleas lack wings and have modified hind legs for jumping (77) (Fig. Formalin should not be used if the specimens will be permanently mounted later, as the formaldehyde fixes the tissue in ways that can make clearing more difficult (19). Pseudoparasites. Throughout the book, the authors vast experience and dedication are evident. Centers for Disease Control and Prevention 2007;13(9):1442. https://doi.org/10.3201/eid1309.070706. Mites. (E) Bat bug (Cimex sp.) This can be seen in cases involving the sarcophagid Wohlfahrtia and the calliphorids Chrysomya bezziana (the Old World screw-worm fly) and Cochliomyia hominovorax (the primary, or New World, screw-worm fly) (Fig. In southern Africa, Rhipicephalus appendiculatus is also a vector of Rickettsia conorii. Also, ixodid ticks have mouthparts (capitulum) visible when viewed from above, while argasid ticks have their mouthparts hidden from above (24, 25). 2009. Ixodid ticks are characterized by the presence of a dorsal shield (scutum) and by having their mouthparts visible from above. They are scavengers on dried protein material, including dead insects, dry animal feeds, smoked fish and meat, feathers, silk, and fur, and may be pests in granaries (135). 1978. Arthropods collected from patients should be promptly placed into a liquid preservative for transportation to the laboratory in order to avoid desiccation or decomposition, which will alter morphological features, potentially rendering the specimens unidentifiable. (Courtesy of the CDC-DPDx.). Goddard, J., & Zhou, L. (2007). In these cases of zoonotic myiasis, the larvae usually do not develop past the second instar. but can be separated based on characteristics of the dorsal shield, forecoxae, and anal plates in the males. Therefore, it is important that extracted larvae are placed into a liquid preservative as quickly as possible after collection for transportation to the laboratory. Several argasid ticks in the genera Argas and Carios that normally feed on bats and birds may come into homes and feed on humans in the absence of their normal host (23, 57, 58); however, these species are not efficient vectors of agents of disease. View the article/chapter PDF and any associated supplements and figures for a period of 48 hours. (Courtesy of the CDC-DPDx.). The mites do not burrow into the skin like scabies mites but rather insert their mouthparts into the skin and inject an irritating secretion that dissolves the surrounding tissue (2). INTRODUCTION. In North America, the two most important species are I. scapularis (Fig. In Europe, D. marginatus is a vector of tick-borne encephalitis viruses (23), and in Europe and Asia, D. silvarum and D. nuttalli are vectors of Rickettsia sibirica (Siberian tick typhus) (49). Wormser GP, Dattwyler RJ, Shapiro ED, Halperin JJ, Steere AC, Klempner MS, Krause PJ, Bakken JS, Strle F, Stanek G, Bockenstedt L, Fish D, Dumler S, Nadelman RB. Their spread. He received his B.S. Also, arthropod identification can play an essential role in the control of some public health arthropod pests or vectors. Of the arachnids, only. can be recognized by having relatively short mouthparts in relation to the basis capituli, the presence of eyes and festoons, and an ornate dorsal shield. When it is known that the larvae submitted are not of public health concern, they should be reported as no parasites found, arthropod, not of public health concern, or similar. Subphylum Crustacea and its medical significance 3. (ed.) In some cases (especially zoonotic cases), second-instar larvae may be received by the laboratory. (D) Phormia sp. 3B). Posterior spiracle with peritreme absent (or very weak and ill defined) or, if present and obvious, without three distinct slitssee step 10. Patients will often present larvae collected from their toilets and bath tubs with the concern that they were shed in their stool or urine. Urinary myiasis associated with urethral stent placements. The fifth edition of Physicians Guide to Arthropods of Medical Importance has been thoroughly updated to ensure authoritative coverage of this complex and fast-moving discipline of arthropodborne diseases, and serves as a reliable reference covering all of the major aspects of entomology. Nymphs (Fig. 2I). Federal government websites often end in .gov or .mil. Rickettsia felis as emergent global threat for humans. Body lice are readily recognized by their morphological features. These specimens are usually anthropophilic species (preferring to reside near or with humans rather than with other animals) and are not parasitic in nature. US Department of Health, Education, and Welfare She obtained her medical degree from the University of Vermont and also holds a master's degree in Medical Parasitology from the London School of Hygiene and Tropical Medicine and a diploma in Tropical Medicine from the Royal College of Physicians in London. Final media for permanent mounts include chloral-gum media, balsam, Permount (Fisher Scientific, Pittsburgh, PA), and isobutyl methacrylate (20). Very frequently, insects and other arthropods submitted to clinical diagnostic and reference laboratories represent incidental findings and are not of public health importance. PDF download. For nonparasitic arthropods or arthropods not of public health importance, a report of no arthropods of medical importance found, no parasites found, or similar is usually sufficient, unless identification is relevant for pest control or public health purposes. Posterior spiracle with three distinct slitssee step 11. Many different methods have been devised for collecting medically important insects, some of which are very simple while others are more complicated and make use of ingenious traps. Linking to a non-federal website does not constitute an endorsement by CDC or any of its employees of the sponsors or the information and products presented on the website. Physiol. Only gravid females are cutaneous parasites. 8600 Rockville Pike For example, with Ixodes (several species of which are vectors of Lyme disease spirochetes), males do not attach for long periods of time and are unlikely to have sufficient contact time to transmit borreliae (30). 1989. A Mol. The concept of symptomatic treatment at the local level may no longer be sufficient to treat certain major types of arthropod-transmitted diseases, such as West Nile virus encephalitis. Posterior spiracles of the third-instar larvae of myiasis-causing flies. Outbreaks of louse-borne diseases usually occur in poorly developed areas where people live in filthy, crowded conditions as well as in institutionalized settings and prisons; otherwise, cases of body lice are relatively rare today. Fauna Saudi Arabia, A review of Asian Amblyomma species (Acari, Ixodida, Ixodidae), Insects of Micronesia. Both species are vectors of the bacteria causing RMSF and tularemia and have been implicated in tick paralysis (2, 23). Scabies is a highly contagious condition that results in the formation of open sores and linear tracks as the mites burrow in the skin. Previous Figure Next Figure. Earthworms can be of public health concern but as intermediate or paratenic hosts for parasites following ingestion (123) rather than as parasitic agents themselves. In Europe, I. ricinus is a vector of organisms causing Lyme disease, babesiosis, and European tick-borne encephalitis (23). (H) Dermatobia hominis. (Panel B courtesy of the CDC-DPDx.). Temporary wet mounts include placing the organism in a drop of 50% ethanol or chloral-gum medium under a glass coverslip (20, 28). Ultimately, it is the responsibility of the medical director to determine the extent of identification required to best serve the clinical needs of their patients. Pchelkin AP, Korenberg EI, Vakhrusheva ZP, Pchelkina AA. are cutaneous parasites that are usually discovered upon microscopic examination of biopsy specimens or skin curettings of lesions on the feet and toes (79). 2004. Arthropods commonly encountered by tourists in countries outside the United States, such as Tunga spp. In Africa, O. moubata transmits African TBRF spirochetes (23). Slits of posterior spiracles straightsee step 3. However, it can be differentiated from X. cheopis by not having the mesopleuron divided by internal scleritization (67). Rochlin I, Ninivaggi DV, Hutchinson ML, Farajollahi A. and P. severini Tonn. (C) Oeciacus vicarius (antenna). 2E and andF)F) in the East and Gulf Coast states and I. pacificus on the West Coast. One of the most common is conjunctivitis caused by the first-instar larvae of the nasal bot fly of sheep, Oestrus ovis (Fig. The most common agents of dermal and subdermal myiasis are Dermatobia hominis (Oestridae) and Cordylobia anthropophaga (Calliphoridae). For nearly 20 years, the award-winning, bestselling Physician's Guide to Arthropods of Medical Importance has established itself as a standard reference in doctors' offices and emergency rooms. Mumcuoglu I, Akarsu GA, Balabam N, Keles I. They have been implicated as a source of household allergies (132, 133). (1978) Surveillance and Collection of Arthropods of Veterinary Importance, U.S. Dept. Colonization of wounds with fly larvae may occur anywhere on the body, including in the ears, nose, and mouth (18). References for regional keys for species-level identification are given below for each genus under their individual sections (see Fig. Members of the genus Dermestes can serve as intermediate hosts for the cestodes Hymenolepis diminuta and H. nana, and thus, human infection may result following ingestion of the beetles (138). Most notably, they can be biological vectors of disease-causing organisms, including those organisms that cause malaria, filariasis, yellow fever, dengue fever, plague, babesiosis, typhus, Lyme disease, Chagas disease, and many others. The Centers for Disease Control and Prevention (CDC) cannot attest to the accuracy of a non-federal website. If a tick is to be mounted, it may first require clearing in KOH and dehydration in alcohol. Hyalomma spp. The https:// ensures that you are connecting to the Human myiasis-causing flies that are found nearly worldwide include Calliphora, Lucilia, Sarcophaga, Phormia, Musca, and Gasterophilus species, while the human myiasis-causing flies with restricted geographic locations include Wohlfahrtia spp. 3A). Cutaneous myiasis: is Lucilia cuprina safe and acceptable for maggot debridement therapy? 2005. Cookies used to enable you to share pages and content that you find interesting on CDC.gov through third party social networking and other websites. If you do not allow these cookies we will not know when you have visited our site, and will not be able to monitor its performance. Yamaguti N, Tipton VJ, Keegan HL, Toshioka S. We have also included information below for Hyalomma, an Old World genus of medical importance that has been seen in returning travelers. Medically, the most important species are in the genus Ornithodoros. Identification is usually made by the examination of mites, their eggs, or their feces in skin scrapings. Tropical diseases. 4B and andC),C), is a cosmopolitan parasite of humans. The lice reside primarily on the clothing and fomites of infested individuals and migrate to the human body periodically to feed (2). 8B). Cogan, B. H. and Smith, K. G. V. (1974) Insects. (A) Pediculus humanus capitis. Pulex irritans is a nearly cosmopolitan parasite, primarily of humans. Head lice are primarily nuisance pests in otherwise healthy children, but secondary bacterial infection can rarely occur. Arthropods of medical importance include vespids, ticks, mosquitoes, mites, flies, and fleas. Otobius megnini is the spinose ear tick of cattle found in the Americas, Africa, India, and Australia. Occasionally, additional damage to the host can occur due to secondary bacterial infections or colonization by secondary invaders (18). The following key will aid in the identification of the more common myiasis-causing flies and saprophagous genera likely to be submitted to clinical and reference diagnostic laboratories (67). There are relatively few species of public health importance, however (2). (I) Hypoderma sp. Comp. Eggs (nits) are glued to the fibers of clothing, unlike other human lice (head and pubic lice), in which eggs are glued to hairs (72). In the continental United States, Ixodes spp. Address correspondence to Blaine A. Mathison, Inverted, U-shaped anal groove extending anteriorly around the anus (, Basis capituli hexagonal, posteriorly directed inwards (, Palps about as long as basis capituli; second palpal segment about as long as it is wide (, Dorsal shield ornate; coxa I with large paired spurs of unequal length; festoons regular. 6A and andD),D), the head is slightly convex (67). Material IV Sympozjum Akaroentomologii Medycznej I Wterynaryjnej. Results For the systematic review and meta-analysis, 1,513 studies were found, and 72 met the inclusion criteria; for the genetic analysis, we found 16 GWASs, 1 nonhuman primate study, and 16 imaging reviews. Loading . The species most frequently involved in such cases are the house fly, Musca domestica, and the lesser house fly, Fannia canicularis. 1996. Arthropods of medical importance include. doi: 10.1128/9781683670438.MCM13.0012.2021.ch151. Earthworms are easily recognized by being segmented and having setae on each body segment and the presence of a clitellum (Fig. 9A). Storage of specimens at 20C or 70C may facilitate DNA recovery (21, 22). CDC twenty four seven. As the importance of medical entomology increases, access to up-to-date, authoritative information also becomes increasingly critical. Urogenital myiasis due to Chrysomyia bezziana, Morphology and biology of the bed bug, Cimex hemipterus (Hemiptera: Cimicidae) in the laboratory, Aspects of the biology of Psychoda alternata (Say.) These usually represent cases of incidental myiasis caused by the colonization of catheters, syringes used for douching, or other instruments that may be contaminated with bodily fluids desirable for saprophagous fly species (18, 105). Four major extant groups of arthropods have members of medical importance 2620 Arthropods as Vectors He also teaches diagnostic morphology workshops for Parasitology and Medical Entomology. Many of the free-living aquatic fly larvae can be readily separated from myiasis-causing calliphorids and oesterids by the presence of a distinct head capsule (Fig. All stages (including eggs) are found on human hair, most commonly in the pubic and perianal regions but also on eyelashes, eyebrows, facial hair, and other coarse body hairs (2, 73,75). Adult fleas are on average 2.0 to 6.0 mm in length and have laterally compressed bodies. Control of arthropods of medical importance Physical control Biological control Chemical control . Skin scrapings are occasionally submitted to a clinical parasitology laboratory for diagnosis of scabies. Integr. Distribution and prevalence of spotted fever group rickettsiae in ticks from South Carolina, with an epidemiological survey of persons bitten by infected ticks, Ecology of Crimean-Congo haemorrhagic fever, Ecological dynamic of tick-borne zoonoses. It covers identification of arthropods and common signs and symptoms of vector-borne disease. They are also much more common and tend to be seen in school-aged children (71). This is a preview of subscription content, access via your institution. An outbreak on a medical mission boat in the Amazon, Bites and stings of medically important venomous arthropods. Several arthropods may require clearing and mounting on microscope slides for identification and may be permanently mounted for archival and teaching purposes (20). ); the infection is highly contagious and requires barrier precautions, including gloves and gowns, for individuals coming into contact with the patients. Inflammatory responses, however, can sometimes be severe, resulting from allergic reactions to the bugs' salivary proteins (2). Hanelt B, Thomas F, Schmidt-Rhaesa A. Brussels Mus. In fact, fly maggots such as Lucilia sericata and L. cuprina are not uncommonly used for debridement therapy (90, 91). no. Regional keys for Amblyomma identification are available for North America (24, 25, 32, 36, 139), Central and South America (36, 37), Africa (38, 39), Asia (40,45), and Australia and Oceania (46, 47). However, when in doubt, the presence of eyes should rule out Ixodes. Educational awareness of signs and symptoms of arthropodborne diseases will reduce unnecessary panic in the event of outbreaks and assist clinicians in differential diagnosis and treatment. Lesions can be extremely painful, and secondary bacterial and myiasis infections can occur (79). The larval mites feed on the liquefied tissue. Formalin is also acceptable, but its use has decreased in recent years due to concerns of its toxicity. Occasionally, humans may also be fed upon by bird and bat cimicids, but this usually occurs only in the absence of the natural host (i.e., following removal of birds or bats from a dwelling or the natural migration of birds) (107). Class Crustacea (copepods, crabs, crayfish, etc.) I. Ticks of the Sudan (with special reference to Equatoria province and with preliminary reviews of the genera Boophilus, Magaropus, and Hyalomma), US Naval Medical Research Report NM 005 050.29.07, The scutate ticks, or Ixodidae, of Indonesia, Ticks (Ixodoidea) of Borneo and Malaya. Eventually, she will die and may be sloughed by the host's skin. 1986. Sabrosky, C. W. (1971) Packing and shipping pinned insects, Bull. Larvae usually live in the vicinity of the host and feed on feces and other organic material. Her chief academic interests lie in trainee education, parasitology, molecular diagnosis of infectious diseases, and infectious disease pathology. While a notorious pest of cattle, there are a few cases in people that have been documented (2, 23, 56). Provided by the Springer Nature SharedIt content-sharing initiative, https://doi.org/10.1007/978-1-349-16334-2_27. Myiasis is colonization or infestation of human or animal tissue with fly larvae (maggots) (1, 18, 88). Cookies used to track the effectiveness of CDC public health campaigns through clickthrough data. We emphasize that the keys presented are for guidance in the identification of arthropods frequently submitted to the clinical laboratory. Key characteristics in identifying ixodid ticks to the genus level include the length of the mouthparts (palps, in relation to the basis capituli), presence or absence of eyes, presence or absence of festoons, color or markings on the dorsal shield, and shape and orientation of the anal groove (Fig. Several mites of birds and mammals will sometimes bite humans and are occasionally sent to diagnostic laboratories for identification. Centers for Disease Control and Prevention. Eggs of Tunga spp. World Health Organization (1975) Manual on Practical Entomology in Malaria. The most common agents of facultative myiasis in wounds are members of the family Calliphoridae (Lucilia and Phormia). (F) Musca sp. If a tick is observed on a person, it should be removed as quickly and safely as possible. Humans may also occasionally become temporary hosts for livestock or avian lice, but these parasites cannot survive on human blood and eventually die and fall off (66). (A) Amblyomma americanum (female). The major anatomic sites of myiasis are discussed below, with the most commonly implicated species being noted. Lice and their nits should be collected in 70 to 80% ethanol and may be mounted on a microscopy slide for more detailed study (19, 72). Adults mate in the environment, and the newly mated females penetrate the stratum corneum and burrow into the stratum granulosum, with only the posterior end of the abdomen being exposed to the environment (12). 2008. Dermacentor spp. Collaborative Activity to Learn Arthropod & Microbial Microbes receive even less recognition than arthropods; despite their immense ecological and medical importance in nutrient ARTHROPODS. Argasidae, Ixodidae. Other arthropods and other organisms not of public health concern, but routinely submitted to laboratories for identification, are also briefly discussed. There are scattered reports in the literature of infection in humans (127, 128), but these are most certainly due to incidental findings and not true infection. It is less desirable to subject an arthropod to histological sectioning and staining, since such processes make interpretation of morphological features challenging. In Africa, A. variegatum is a vector of Crimean-Congo hemorrhagic fever (CCHF) virus (35), and A. hebraeum is a vector of Rickettsia conorii (boutonneuse fever) (2). Arthropods of Medical Importance. (56). Adult mites are 0.2 to 0.4 mm long and broadly oval, with rudimentary legs (Fig. and myiasis-causing flies, are also discussed. They typically have a very rough, granulate texture to their dorsal tegument. Dermacentor ticks (Acari: Ixodoidea: Ixodidae) of the New World: a scanning electron microscope atlas, Ixodid ticks (Ixodidae). Frampton M, Droege S, Conrad T, Prager S, Richards MH. These cookies may also be used for advertising purposes by these third parties. Mites are typically only occasionally submitted to diagnostic laboratories. Jones EK, Clifford CM, Keirans JE, Kolhs GM. They possess well-developed eyes and antennae and have piercing-sucking mouthparts (Fig. Included are data on ticks, mites, lice, fleas, myiasis-causing flies, and bed bugs. Fly larvae are soft bodied and prone to desiccation. Second and third instars of D. hominis can be recognized by the lack of cuticular spines on the last three body segments (Fig. (12). Identification to the genus or species level can be difficult and is best done by a trained specialist (i.e., acarologist or entomologist), as they are separated by microscopic examination of the mouthparts, respiratory tract, and various plates on the body. The collection, handling, identification, and reporting of ectoparasitic arthropods in clinical and reference diagnostic laboratories are discussed in this review. They are ubiquitous and occur in most homes. Instead, only the more commonly encountered groups seen in diagnostic laboratories are discussed here. Talari S-A, Sadr F, Doroodgar A, Talari M-R, Gharabagh A-S. Nymphs are similar to the adults but smaller. Written in a clear and readable style, the text presents complex, academic information on the biodiversity of arthropod pests that even a lay person can understand. (H) R. sanguineus (ventral). (D) Psychodid fly larva (red arrow, head capsule; black arrow, respiratory siphon). (C) C. lectularius (early-instar nymph). Arthropods of Medical Importance March 2015 Conference: Environmental Health Australia, Environmental Health School At: Sydney Olympic Park Authors: Stephen L. Doggett Westmead Hospital Download. Lice. The Altmetric Attention Score for a research output provides an indicator of the amount of attention that it has received. Unfortunately, after an identification is made, it is not uncommon for case reports to be published (116,120), perpetuating the belief that these flies cause clinical disease in humans. However, molecular data suggest that the two groups are actually two ecotypes of the same species and that evolution between the two populations takes place continually (71). (B) Cochliomyia hominovorax (third instar). The following key will help facilitate identification of medically important ixodid ticks to the genus level (adapted from reference 24). There are over 700 species worldwide, only about 20 of which cause dermatitis in humans, including in the United States (2). The most common larvae submitted are free-living species (usually drain flies in the family Psychodidae and rat-tailed maggots in the family Syrphidae) that breed in standing water, including toilets (see Pseudoparasites, below). and chiggers (trombiculid mites, also known as common harvest mites) may also be of medical importance in certain settings. Download preview PDF. Three of the more common genera of such infestations are Gasterophilus, Cuterebra, and Hypoderma. The larvae may also be forwarded to a professional entomologist or reference laboratory for further identification. While most arthropods discussed in this review are insects, we also discuss the arachnids in the Acari taxon, namely, ticks and mites. I. Bionomics with reference to epidemiology in the United States, Mites of public health importance and their control, Common lice and mites of poultry: identification and treatment. Adults are characterized by lacking both pronotal and genal combs and having the mesopleuron divided by internal scleritization (hardening) (Fig. (Courtesy of the CDC-DPDx.). Also, if the specimen was not manipulated too badly, the location in the tissue could be helpful; Sarcoptes usually resides in cutaneous burrows, whereas Demodex is found in sebaceous glands and hair follicles (63). McNutt, D. M. (1976) Insect Collecting in the Tropics, ( Centre for Overseas Pest Research, H.M.S.O., London ), 68 pp. Chiggers are mites in the family Trombiculidae. Pest Bull., no. Emerg Infect Dis. (D) Cimex sp. Physiol. (C) Sarcophaga sp. In these cases, the arrangement of the legs may prove to be the most helpful morphological feature. They may be confused with bed bug nymphs but have chewing mouthparts and more than five antennal segments (134). Morphologically, they are similar to body lice albeit generally slightly smaller. develops and multiplies in the vector,andis transmitted to humans via arthropod's. bite or excreta (mosquitoes, tsetse-flies, body lice, fleas). (I) Tunga penetrans excised from a lesion (arrow, egg). Posterior spiracle without three distinct slitssee step 13. Between feedings, they are usually hidden away under mattresses or under floor boards, etc. Cases of wound myiasis are often seen in patients presenting with malignant tumors containing necrotic tissue (92, 93) and in intravenous drug users (94). https://doi.org/10.1007/978-1-349-16334-2_27, DOI: https://doi.org/10.1007/978-1-349-16334-2_27, eBook Packages: Biomedical and Life SciencesBiomedical and Life Sciences (R0). Hamer SA, Tsao JI, Walker ED, Hickling GJ. His chief academic areas lie in diagnostic Parasitology and Medical Entomology (but he also has an extensive background in Bacteriology and Mycology) and serves as the Webmaster for the DPDx website. Sarcoptes mites reside in the epidermis, generally in the stratum corneum. The most common are the tropical rat mite (Ornithonyssus bacoti), tropical fowl mite (O. bursa), northern fowl mite (O. sylviarum) (Fig. Dermatobia hominis is neotropical in distribution and, despite the species epithet, can inhabit many mammal species (98). Prez-Osorio CE, Zavala-Velzquez JE, Lon JJA, Zavala-Castro JE. Skin scrapings should be screened at a 40 or a 100 magnification and then evaluated at a magnification of 200 to 400 for confirmation (20, 61). These include hard ticks, soft ticks, scabies mites, chiggers, Demodex mites, zoonotic biting mites, lice, bed bugs, and fleas. 1). Kingu HJ, Kuria SK, Villet MH, Mkhize JN, Dhaffala A, Iisa JM. Careers, Unable to load your collection due to an error. Malaya, Ixodid ticks (Acarina, Ixodidae) of West Pakistan. Classification of Arthropods. (arrows show the relative length of pronotal setae to the width of the eye, head, and pronotum). In severe cases, patients may present with thick layers of crust on the skin, a condition referred to as Norwegian, or crusted, scabies. Rhipicephalus sanguineus (brown dog tick) (Fig. ), Bed bugs. Eristalis tenax as a cause of urinary myiasis. Yamada M, Tegoshi T, Abe N, Urabe M. III. (D) D. variabilis (male). Mites, as delineated here, are the nontick Acari. Jerome Goddard recently appeared on The Colbert Report. The main checklist covers Arthropods (pp. As mentioned above, the fact that the parasitic females are embedded in human skin means that individual Tunga fleas are not typically submitted to diagnostic laboratories for identification. Fleas submitted to diagnostic laboratories should be placed into 70 to 80% ethanol. They possess antennae, sucking mouthparts, and (usually) eyes. Hoogstraal H, Wassef HY, Bttiker W. Sanders ML, Scott AL, Glass GE, Schwartz BE. (Adapted from reference 67.). 2005. The most common and aggressive species in North America is A. americanum, whose females are readily recognized by the single white macula (spot) on the posterior region of the dorsal shield (hence the common name lone star tick). sp., and a revised key to the species (Acari: Mesostigmata: Dermanyssidae). Fleas are only occasionally submitted to diagnostic laboratories and typically only in the adult form. Fire and petroleum jelly should never be used, since they can cause the tick to regurgitate and enhance the spread of infectious agents. Key features of bed bugs and related cimicids. There are many ways in which arthropods can be of public health or medical importance. 9C) resemble the adults but are smaller, lack the rudimentary wing buds, and tend to be paler in color (109, 110). Unlike Ornithodoros spp., O. megnini is parasitic only in the larval and nymphal stages. Therefore, they may be submitted to the laboratory only rarely. Data is collected weekly and does not include downloads and attachments. Posterior spiracle with peritreme present, with three distinct slitssee step 2. Adults and nymphs have the typical raptorial (grasping) tarsal claws seen in the other parasitic lice. (agent of babesiosis) (23). (E) Earthworms (arrow, clitellum). His main research interests are the ecology and epidemiology of tick-borne diseases, the health and medical impacts of bed bugs, and mosquitoes and mosquito-borne diseases. They help us to know which pages are the most and least popular and see how visitors move around the site. This book is intended to provide a single, reliable source for checking the scientific names and taxonomic position of arthropods of medical and veterinary importance (i.e. They are vectors of several very important diseases (Table 1) and may be implicated in tick paralysis (2, 23). In general, we recommend that ticks (hard and soft), scabies and Demodex mites, lice, and fleas be reported to the genus level or even the species level when possible. Overview of vector-borne diseases and the arthropods that transmit them. Finally, it is important to note that arthropod identification is best accomplished through microscopic and macroscopic identification of an intact specimen. The posterior spiracles reside in a deep cavity, and it may be difficult to discern them grossly. While histological workup is often required for tissue biopsy specimens, individual arthropods (or parts) are best left intact. Bethesda, MD 20894, Web Policies After removal, the tick may be sent to the laboratory in a dry container or can be placed into collection medium as quickly as possible. Collecting, Preparing, and Preserving Insects, Mites and Spiders (Biosystematics Research Institute, Ottawa, Ministry of Supply and Services, Hull, Quebec, Canada), Publ. A related species, Amblyomma maculatum, is a nuisance pest in the southeastern United States but has been incriminated in the transmission of RMSF in South Carolina (34) and is a known vector of Rickettsia parkeri, the causative agent of Tidewater spotted fever. There are two species found on the human host, D. folliculorum and D. brevis, and both are thought to be acquired from household contacts (62). Ticks are one of the most medically important groups of arthropods. (E) C. canis (closeup of head). Adult fleas successfully removed from lesions possess well-developed eyes and legs but lack pronotal and genal combs (Fig. Loving SM, Smith AB, Disalvo AF, Burgdorfer W. Ticks of public health importance and their control. (J) Cuterebra sp. 11D, red arrow), long and fine setae, and respiratory siphons (Fig. Pinckney J, II, Cole P, Vadapalli SP, Rosen T. Mem. You can also search for this author in Like the argasid ticks, bed bugs are intermittent feeders and do not reside on the host for prolonged lengths of time. First-instar larvae remain under the sand until coming into contact with an appropriate host. Insects, spiders, crabs, and lobsters are all arthropods, so there are a lot of arthropods on Earth. Scratching may result in secondary bacterial infections. Posterior spiracle incomplete, not enclosing a sometimes poorly defined buttonsee step 5. If the larvae are of an early instar that complicates identification or are damaged beyond reliable identification, and the clinical picture and collection methods are not helpful in determining the validity of the case, they may be reported simply as fly larvae (or similar). Hist. Am., 17; 68. As such, it is important for the clinical diagnostic laboratory to identify ticks to at least the genus level and preferably to the species level in many clinical settings. In skin scrapings, adults are readily recognized by their slender, elongated bodies measuring 0.1 to 0.4 mm in length (63) (Fig. Pubic lice are primarily a nuisance pest, and often, the social stigma of the disease can be more detrimental than the physical effects of the infestation. The most common fly larvae seen in these scenarios are drain flies (Psychodidae) and rat-tailed maggots (Syrphidae). are much larger, however, measuring 600 m in length on average (12) (Fig. No species are effective vectors of disease-causing organisms in humans, although they have been found to be naturally infected with many blood-borne pathogens (2, 108). Bram, R. A. The author concludes with personal protection methods against arthropods.Now with color pictures throughout, the Sixth Editions chapters have been updated with the latest information and current references. Expanding geographical distribution of the mosquito Culex pipiens, in Canada under climate change. AG, anal groove; BC, basis capituli; DS, dorsal shield; EY, eye; FS, festoons. Wiad. (Nematocera: Psychodidae). It can also transmit R. typhi, the causative agent of murine typhus. Table of Contents Volume 13, Number 9September 2007. Unlike body lice, head lice reside on the human host at all times, and all stages (including eggs) are found on human hair (72). The text also covers all harmful effects on human health and highlights current management recommendations. In biopsy specimens, where the mites may be sectioned at odd angles, it may be more difficult to identify them. Fam. More often than not, these cases are usually initiated with the patient bringing in larvae reportedly found in their feces or urine or that of a friend or family member. Jiang J, Soeatmadji DW, Henry KM, Ratiwayanto S, Bangs MJ, Richards AL. Reporting of results for arthropods submitted to clinical and reference laboratories can often be challenging due to the large variety of specimens received (including both human and nonhuman parasites) and the wide variation in arthropod identification skills among laboratories. Adults are oval in shape and dorsoventrally flattened. Xenopsylla cheopis has been found to be naturally infected with R. felis, but its potential as a true vector of this organism is undetermined (87). Part 1, Collecting, preparing, and preserving insects, mites, and spiders. The reaction of the host on the parasite invasion. Anatomy of the flea. (North, Central, and South America), Hypoderma spp. Medically important arthropods have long been considered to m. (A) Ctenocephalides felis. (Adapted from reference 67. Arthropods of Medical Importance Authors: Blaine A. Mathison Last Updated: 2021 Tools Introduction Arthropods comprise a diverse group of invertebrate animals, united by a common body plan of a jointed, chitinous exoskeleton. It is important not to twist or jerk the tick, to allow for removal of as much of the mouthparts as possible. Pupation takes place in a silken cocoon covered with sand grains or dust (76). They are characterized by long mouthparts and a shortened body. In male ixodid ticks, the dorsal shield covers most of the dorsum, whereas in the females, it is usually restricted to the anterior third to half of the dorsum. Unfortunately, there is significant size overlap between head and body lice, and therefore, size is not a reliable differentiating feature. The score is derived from an automated algorithm, and represents a weighted count of the amount of attention Altmetric picked up for a research output. (C) Dermacentor variabilis (female). (G) C. lectularius (head and pronotum) (the arrow shows the degree of concavity of the anterior margin of the pronotum). Lane, J. Anyone you share the following link with will be able to read this content: Sorry, a shareable link is not currently available for this article. Ethanol-based preservatives should be used if the specimen will eventually be permanently mounted on a microscope slide. ) can not attest to the laboratory only rarely with three distinct slitssee step 2 a lot of and... 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