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7 Bug Bites You Need to Know
Bo Burns, DO, FACEP, FAAEM | June 13, 2022
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Image courtesy of Wikimedia Commons | Correogsk.
7 Bug Bites You Need to Know
Bo Burns, DO, FACEP, FAAEM | June 13, 2022 | Contributor Information
Lesions from bedbug (Cimex lectularius) feeding sites are seen above.
Insect bites can give rise to signs and symptoms ranging from skin irritation to life-threatening disease. The World Health Organization (WHO) states that globally, vector-borne diseases, including those transmitted by insects, result in 700,000 deaths per year,[1] while according to the US Centers for Disease Control and Prevention (CDC), infections caused by mosquitoes, ticks, and fleas increased by 300% between 2004 and 2016.[2]
Image from the CDC | James Gathany.
7 Bug Bites You Need to Know
Bo Burns, DO, FACEP, FAAEM | June 13, 2022 | Contributor Information
Lice
Pictured above, a female body louse (Pediculus humanus corporis) feeds on a human host.
Lice are parasitic insects from the suborder Phthiraptera. The three types of louse that feed on humans are Pediculus humanus capitis (head louse), Pediculus humanus corporis, and Pthirus pubis (pubic louse; also called the "crab" louse).[3] Only body lice are known to spread disease,[3] being vectors for three major bacterial disorders: typhus, trench fever, and relapsing fever. Additionally, irritation from bites can lead to excoriation and secondary bacterial infections.[4]
Body louse infestation correlates with poor hygiene, overcrowding, and cold or damp conditions. People who are homeless, incarcerated, or refugees are at higher risk for hosting lice and contracting louse-borne diseases.[4]
Image from Wikimedia Commons | ZeWrestler | (inset) Mike Quinn, TexasEnto.net.
7 Bug Bites You Need to Know
Bo Burns, DO, FACEP, FAAEM | June 13, 2022 | Contributor Information
Fire Ants
The above-pictured pustules and blisters developed after red imported fire ant (Solenopsis invicta) envenomation of the leg. S invicta's venom contains alkaloids, proteins, and enzymes; the proteinaceous components may account for the anaphylactic reaction that can occur.[5] Many patients have venom-specific immunoglobulin E–mediated wheal-and-flare reactions, which develop into pruritic, edematous, indurated, erythematous lesions that persist for up to 72 hours.[6]
When anaphylactic reactions arise, epinephrine is administered and repeated every 10-15 minutes to reverse the symptoms. Local reactions can be treated with antihistamines and cool compresses. Topical steroids may be useful, and in severe cases, oral prednisone may be employed. Venom immunotherapy can be used to decrease the risk of systemic reactions.[7]
Image from Wikimedia Commons | Slturis.
7 Bug Bites You Need to Know
Bo Burns, DO, FACEP, FAAEM | June 13, 2022 | Contributor Information
Mites
Trombiculosis is a rash caused by the larvae of trombiculid mites (chiggers) as they feed on skin cells. (The above image shows a chigger rash 36 hours post exposure.) Mite saliva gives rise to intense irritation, with severe itching and dermatitis, and often produces hard, raised bumps. There is a risk of secondary infection if the bites are scratched open.
Chiggers have not been shown to carry diseases in the United States, but in East Asia and Austronesia they can transmit Orientia tsutsugamushi, an obligate intracellular pathogen responsible for scrub typhus (Japanese river disease). New developments in the field of videodermatoscopy allow for rapid, noninvasive diagnosis of trombiculosis and other skin lesion disorders.[8]
Image from the CDC.
7 Bug Bites You Need to Know
Bo Burns, DO, FACEP, FAAEM | June 13, 2022 | Contributor Information
Ticks
The above-pictured rash is associated with Rocky Mountain spotted fever (RMSF), a tick-borne disease. Ticks collectively transmit more varieties of disease than any other group of blood-feeding arthropods.[9]
Rocky Mountain spotted fever
RMSF is caused by the bacterium Rickettsia rickettsii, which is transmitted to humans by the bite of infected ticks. The development of a rash in the setting of recent outdoor activity, usually by day 6, is a major diagnostic sign of RMSF. However, about 10-15% of patients with RMSF never develop a rash. Doxycycline is the first-line treatment for RMSF in adults and children.
The American dog tick (Dermacentor variabilis), found east of the Rocky Mountains and in California,[10] is the most commonly identified source of RMSF transmission.
Image from Medscape.
7 Bug Bites You Need to Know
Bo Burns, DO, FACEP, FAAEM | June 13, 2022 | Contributor Information
Lyme disease
Erythema migrans, a rash caused by Lyme disease, is shown above.
Ixodes scapularis (commonly known as the deer tick or black-legged tick) can transmit the spirochete bacterium Borrelia burgdorferi, which causes Lyme disease.[11]
Patients with Lyme disease often present with a characteristic red, expanding rash (the above-mentioned erythema migrans), typically on the torso. Multiple lesions of erythema migrans occur in about 20% of patients; other typical symptoms include fever, headache, and fatigue.[12] A number of antibiotics may be used to treat early Lyme disease.[13] If the disorder is left untreated, infection can spread to the joints, heart, and nervous system.[12] Some post-Lyme patients also exhibit cognitive impairment.[14] However, individuals who are infected with B burgdorferi can be asymptomatic.[15]
Image from the CDC.
7 Bug Bites You Need to Know
Bo Burns, DO, FACEP, FAAEM | June 13, 2022 | Contributor Information
Ticks attach themselves to their host by means of a cement secreted from their salivary glands. Female ticks are the primary blood feeders, but males can often be found in the vicinity of attached females. In most cases, I scapularis (shown) must be attached for at least 36-48 hours before B burgdorferi can be transmitted. In May 2016, researchers reported the discovery of a new bacterial pathogen in the northern Midwest that can cause Lyme disease, B mayonii.[16]
Image courtesy of Arlo Pelegrin.
7 Bug Bites You Need to Know
Bo Burns, DO, FACEP, FAAEM | June 13, 2022 | Contributor Information
Monocytic ehrlichiosis
The mouthparts of the lone star tick (Amblyomma americanum, shown) include a pair of hooked appendages (pedipalps) that arrange the host's skin into a puncturable mound, along with a hypostome, a blood-absorbing tube covered with overlapping, bladelike scales.
The lone star tick is the principal vector for monocytic ehrlichiosis, which occurs in the south-central and southeastern United States.[17] Although the bacteria Ehrlichia chaffeensis and E ewingii both cause disease in humans, most documented cases of ehrlichiosis have been attributed to E chaffeensis. Doxycycline is the treatment drug of choice for all age groups, and administration should be initiated immediately whenever ehrlichiosis is suspected.[18] Ehrlichiosis can also be transmitted via organ donation.[19]
Image from the CDC | James Gathany.
7 Bug Bites You Need to Know
Bo Burns, DO, FACEP, FAAEM | June 13, 2022 | Contributor Information
Mosquitoes
Dengue fever
Dengue fever is transmitted by mosquitoes of the genus Aedes (above), which are widely distributed in subtropical and tropical areas of the world.[20] Dengue fever (also called breakbone fever, because of the associated joint and muscle pain) often presents in a nonspecific manner, although a number of individuals develop a characteristic rash. Other signs and symptoms may include severe headache, eye pain, mild bleeding, and leukopenia.[21] Many patients experience a prodrome of chills, erythematous mottling of the skin, and facial flushing. About 5% of dengue patients develop severe signs, including plasma leakage, shock, hemorrhage, and acute cholecystitis.[22]
Patients with a history of Zika virus infection have a higher risk of developing serious symptoms from a novel dengue infection.[23]
Froeschl G, Huber K, von Sonnenburg F, et al. BMC Infect Dis. 2017 Jan 10;17(1):55. [PMID: 28068904]
7 Bug Bites You Need to Know
Bo Burns, DO, FACEP, FAAEM | June 13, 2022 | Contributor Information
Zika
The above image demonstrates a diffuse, macular rash in a 41-year-old male patient infected with the Zika virus.
According to the CDC, Zika transmission in the United States has dropped to zero since 2018.[24] In 2021, there was one case acquired abroad and detected in the country.[25]
Like dengue fever, Zika is transmitted by mosquitoes of the genus Aedes. It can also be passed on through sexual contact.
Early indicators of Zika infection include conjunctivitis, as well as fever, maculopapular rash, and joint pain. Zika has been linked to Guillain-Barré syndrome, an autoimmune disorder,[26] while antenatal Zika infections are known to be capable of causing devastating birth defects (eg, microcephaly).[27] As of mid-2022, no specific treatment for Zika virus existed.[28]
Image from Feldmeier H. Trop Med Health. 2014 Jun;42(2 Suppl):15-20. [PMID: 25425946]
7 Bug Bites You Need to Know
Bo Burns, DO, FACEP, FAAEM | June 13, 2022 | Contributor Information
Burrowing Fleas
The scanning electron micrograph above shows the last abdominal segments of a female chigoe flea (Tunga penetrans) protruding from its host's skin.
Tungiasis is an infection caused by the burrowing fleas T penetrans and T trimamillata.[29,30] Adult females embed themselves in the host's skin and cause itching or irritation as they become engorged on host blood. These insects can also infect pets and other domestic animals.[31]
Treatment of tungiasis is usually highly successful if proper sterile methods are followed for flea extraction. Additionally, occlusive agents such as dimeticones and coconut oil have shown promise in addressing the disease.[32,33]
Image from the CDC | Piotr Naskrecki.
7 Bug Bites You Need to Know
Bo Burns, DO, FACEP, FAAEM | June 13, 2022 | Contributor Information
Bedbugs
Common bedbugs (C lectularius; shown) conceal themselves in cracks, margins, and folds around areas used by humans for sleeping. They are attracted to the smell of their own species' urine and thus tend to aggregate in spots where feeding has been successful.[34] Using a stylet-tipped feeding tube, they inject their host with a self-dispersing saliva that digests cells; C lectularius then sucks up the liquefied slurry.
The most commonly reported host response is the development of 2- to 5-mm pruritic, maculopapular, erythematous lesions at bedbug feeding sites.[35]
While their bites are a nuisance, bedbugs have not yet been shown to transmit disease to humans.[36] In laboratory tests, however, C lectularius was identified as a competent vector for Borrelia recurrentis, which causes louse-borne relapsing fever.[37]
Like C lectularius, another Cimex species, C hemipterus, the tropical bedbug, also strongly prefers human hosts.[38]
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Contributor Information
Author
Bo Burns, DO, FACEP, FAAEM
George Kaiser Family Foundation Chair in Emergency Medicine
Associate Professor & Program Director
Department of Emergency Medicine
University of Oklahoma School of Community Medicine
Tulsa, OK
Disclosure: Bo Burns, DO, FACEP, FAAEM, has disclosed no relevant
financial relationships.
Editor
Mark P Brady, PA-C
Adjunct Faculty and Preceptor
Physician Assistant Program
University of New England
Physician Assistant
Department of Emergency Medicine
Cambridge Hospital, Cambridge Health Alliance
Cambridge, MA
Disclosure: Mark P Brady, PA-C, has disclosed no relevant financial
relationships.
Reviewer
Arlo Pelegrin, MSc
Professor of Biology
Community College of Aurora
Aurora, CO
Disclosure: Arlo Pelegrin, MSc, has disclosed no relevant financial
relationships.
Centers for Disease Control and Prevention. Illnesses on the rise: from mosquito, tick, and flea bites. Reviewed May 1, 2018. Available at: https://www.cdc.gov/vitalsigns/vector-borne/index.html. Accessed June 8, 2022.
Centers for Disease Control and Prevention. Parasites - lice. Available at: https://www.cdc.gov/parasites/lice/. September 11, 2019. Accessed June 8, 2022.
Amanzougaghene N, Fenollar F, Raoult D, Mediannikov O. Where Are We With Human Lice? A Review of the Current State of Knowledge. Front Cell Infect Microbiol. 2020 Jan 21;9:474. PMID: 32039050 [Full text].
Baer H, Liu TY, Anderson MC, Blum M, Schmid WH, James FJ. Protein components of fire ant venom (Solenopsis invicta.) Toxicon. 1979;17(4):397-405. PMID: 494321.
Park HJ, Watson NL, Wauters RH. Multisite evaluation of fire ant venom immunotherapy safety and efficacy. Journal of Allergy and Clinical Immunology: Global. 2022 Apr 15. [Full text].
Chen X, Lu Q, Chen C, Jiang G. Recent developments in dermoscopy for dermatology. J Cosmet Dermatol. 2021 Jun;20(6):1611-7. Epub 2020 Nov 28. PMID: 33197276
Estrada-Peña A, Jongejan F. Ticks feeding on humans: a review of records on human-biting Ixodoidea with special reference to pathogen transmission. Exp Appl Acarol. 1999 Sep;23(9):685-715. PMID: 10581710
Wormser GP, Dattwyler RJ, Shapiro ED, et al. The clinical assessment, treatment, and prevention of Lyme disease, human granulocytic anaplasmosis, and babesiosis: clinical practice guidelines by the Infectious Diseases Society of America. Clin Infect Dis. 2006 Nov 1;43(9):1089-134. PMID: 17029130.
Touradji P, Aucott J, Yang T, Rebman AW, Bechtold KT. Cognitive Decline in Post-treatment Lyme Disease Syndrome. Arch Clin Neuropsychol. 2019 Jun 1;34(4):455-65. PMID: 29945190.
Radolf JD, Strle K, Lemieux JE, Strle F. Lyme Disease in Humans. Curr Issues Mol Biol. 2021;42:333-84. Epub 2020 Dec 11. PMID: 33303701 [Full text].
Pritt BS, Mead PS, Johnson DK, et al. Identification of a novel pathogenic Borrelia species causing Lyme borreliosis with unusually high spirochaetaemia: a descriptive study. Lancet Infect Dis. 2016 May;16(5):556-64. PMID: 26856777
Centers for Disease Control and Prevention. Ehrlichiosis: epidemiology and statistics. Reviewed August 4, 2021. Available at: https://www.cdc.gov/ehrlichiosis/stats/index.html. Accessed June 8, 2022.
Saha A, Browning C, Dandamudi R, et al. Donor-derived Ehrlichiosis: 2 Clusters Following Solid Organ Transplantation. Clin Infect Dis. 2022 Mar 9;74(5):918-23. PMID: 34329411
Centers for Disease Control and Prevention. Dengue: symptoms and treatment. Reviewed September 20, 2021. Available at: https://www.cdc.gov/dengue/Symptoms/index.html. Accessed June 8, 2022.
Sharp TM, Morris S, Morrison A, et al. Fatal Dengue Acquired in Florida. N Engl J Med. 2021 Jun 10;384(23):2257-9. PMID: 34107186
Katzelnick LC, Narvaez C, Arguello S, et al. Zika virus infection enhances future risk of severe dengue disease. Science. 2020 Aug 28;369(6507):1123-8. PMID: 32855339 [Full text].
Centers for Disease Control and Prevention. Zika Virus: Zika cases in the United States. Reviewed December 22, 2021. Available at: https://www.cdc.gov/zika/reporting/index.html. Accessed June 8, 2022.
Feldmeier H, Heukelbach J, Ugbomoika US, et al. Tungiasis--a neglected disease with many challenges for global public health. PLoS Negl Trop Dis. 2014 Oct 30;8(10):e3133. PMID: 25356978 [Full text].
Mutebi F, Krucken J, Feldmeier H, von Samsom-Himmelstjerna G. Clinical implications and treatment options of tungiasis in domestic animals. Parasitol Res. 2021 Apr 5. PMID: 33818640
Abrha S, Heukelbach J, Peterson GM, et al. Clinical interventions for tungiasis (sand flea disease): a systematic review. Lancet Infect Dis. 2021 Aug;21(8):e234-45. Epub 2021 Jul 5. PMID: 34237261.
Tardin Martins AC, de Brito AR, Kurizky PS, et al. The efficacy of topical, oral and surgical interventions for the treatment of tungiasis: a systematic review of the literature. PLoS Negl Trop Dis. 2021 Aug 20;15(8):e0009722. PMID: 34415904 [Full text].
Olson JF, Moon RD, Kells SA. Off-host aggregation behavior and sensory basis of arrestment by Cimex lectularius (Heteroptera: Cimicidae). J Insect Physiol. 2009 Jun;55(6):580-7. PMID: 19418598.
Goddard J, deShazo R. Bed bugs (Cimex lectularius) and clinical consequences of their bites. JAMA.2009 Apr 1;301(13):1358-66. PMID: 19336711.
Delaunay P, Blanc V, Del Guidice P, et al. Bedbugs and infectious diseases. Clin Infect Dis. 2011 Jan 15;52(2):200-10. PMID: 21288844 [Full text].
Potts R, Scholl JL, Baugh LA, Pietri JE. A Comparative Study of Body Lice and Bed Bugs Reveals Factors Potentially Involved in Differential Vector Competence for the Relapsing Fever Spirochete Borrelia recurrentis. Infect Immun. 2022 May 19;90(5):e0068321. Epub 2022 Apr 6. PMID: 35384689 [Full text].
Samiei A, Tavassoli M, Mardani K. The Phylogenetic Analysis of Cimex hemipterus (Hemiptera: Cimicidae) Isolated from Different Regions of Iran Using Cytochrome Oxidase Subunit I Gene. J Arthropod Borne Dis. 2020 Sep 30;14(3):239-49. PMID: 33644237 [Full text].
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