Scabies Lorraine L

Home , Cheyletiella, Cheyletiella blakei, Demodex brevis, Demodex folliculorum, Demodicosis, Dermanyssus gallinae

Scabies Lorraine L. Rosamilia, MD

times subtle and divergent features. For instance, the eruption is n Abstract reported to resemble droves of dermatoses including atopic derma- Scabies infestation in humans is a complex interplay be- titis, seborrheic dermatitis, dermatitis herpetiformis, other arthro- tween mite, host, and host environment. New techniques pod assaults, guttate, plaque, palmoplantar and rupioid psoriasis, for diagnosis, treatment, and eradication are constantly in flux due to varying presentations of scabetic eruptions, secondary syphilis and other papulosquamous eruptions, hyper- a dearth of especially sensitive and specific measures sensitivity reactions, and exanthema. Some nodular lesions, partic- for diagnosis, resistances to pharmacologic therapy, and ularly in children, may mimic histiocytoses (both Langerhans and disparate regional resources. This review will provide an non-Langerhans cell types), lymphoma, diaper-based eruptions or update on the clinical variations, detection methods, and infections, or even urticaria pigmentosa, replete with Darier sign.2 management options. Annular pink plaques mimicking tinea and an adult bullous vari- Semin Cutan Med Surg 33:106-109 © 2014 Frontline Medi- ant resembling pemphigoid are reported, and cases of overlapping cal Communications dermatoses like granuloma annulare and elastosis perforans serpiginosa in the vicinity of a scabies mite have also recently been described.3-7 ome disease processes are so familiar that we might assume Evolving insight into the pathophysiology of the infestation that little light can be shed on their detection, management, also demonstrates that scabies is a gateway eruption for new in- Sand broader interface with human health. A trip through the fections, particularly Staphylococccus and Streptococcus species, 30- to 60-day life cycle of the Sarcoptes scabiei var. hominis mite, likely because the skin barrier is vulnerable. Also, scabies mites however, reveals a complex interface between parasite and host, can inhibit complement and promote bacterial growth; for exam- scybala and skin, hygiene and hoards, contagion and crowding, epi- ple, via a mite gut protein type called peritrophin, the mite can ex- demics and economics. Depending on the patient’s immune system press large amounts of the macrophage migration inhibitory factor and comorbidities, home environment and geography, and prior (MIF), which may aid in evasion of the host immune response.8-10 home therapies or treatments offered by other clinicians, diagnostic In addition, because some of the affected patient populations are in and management methods represent feast or famine. At a worldwide developing countries and because some patients, no matter the lo- incidence of 300 million cases each year, this infestation, although cale, may be immunosuppressed, the secondary infections can lead commonplace and familiar, is still a disease process that presents to rheumatic heart disease and other postinfectious complications to our practices, consult services, and communities as undetected (Figure 1).8 Recent reports also suggest that patients with a history or undertreated. This review will provide an update on the clinical of scabies may become vulnerable to chronic kidney disease and variations, diagnostic methods, and management options.1 even other skin eruptions, like pemphigoid variants.11,12

What’s new Diagnostics Protean clinical presentations Office-based direct diagnostic measures still prevail for scabies Classic clinical features and symptoms of human scabies infes- mite identification, as the patients’ extreme pruritus and anxiety tation include well-known descriptors: a particularly nocturnally surrounding their symptomatology mandate expeditious results. pruritic patient, often with a history of institutionalization, group Therefore, initial preferred diagnostic measures include mineral living, immunosuppression, or close contacts with these risk fac- oil slide preparation of a skin scraping using a 15-blade or ‘curette tors; presenting with polymorphic excoriated or crusted pink prep’ using a disposable curette, adhesive tape stripping, burrow papules, burrows, nodules, or plaques, particularly in skin folds. ink test (performed more often in Europe), and dermoscopy.13-15 The clinical variants including classical papular type, Norwegian/ In fact, dermoscopy-guided skin scraping, particularly to visual- crusted type in the immunosuppressed, and rarer nodular and ve- ize the burrowed trail of the mite, seems more accurate than skin siculobullous types, often include a broad differential with some- scraping alone.16 Dermoscopic patterns of triangles termed ‘hang glider’ or ‘delta-wing jet’ for the mite and ‘jet plane tail’ for the burrow have been recently described.17-19 Department of Dermatology, Geisinger Health System, State College, Another novel in-office modality for scabies identification is in Pennsylvania vivo reflectance confocal microscopy which displays: refractive Disclosures: The author has completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest and has nothing to disclose. mite body parts, eggs, scybala (Figure 2), visible mite movement, Correspondence: Lorraine L. Rosamilia, MD; Geisinger Scenery Park; 200 and gut pulsation, the presence or absence of which may deter- Scenery Dr, 56-02; State College, PA 16801. E-mail: llrosamilia@geisinger. mine mite viability after scabicide treatment.20,21 In addition, there edu is serologic testing in development for scabies infestation measur-

Sleep disturbance Itch and scratch Scabies Economic impact

Crusted scabies Impetigo — S. pyogenes and S. aureus

Complicated local Invasive Invasive Rheumatic Glomerulonephritis skin infections S. pyogenes S. aureus fever

Chronic renal Rheumatic disease heart disease

10% case 5% case 5% case fatality 2-5% case fatality fatality rate fatality rate rate per year rate per year n Figure 1. Complications of scabies infestation.Reprinted with permission from Dr. Andrew Steer.8 ing Immunoglobulin E (IgE) antibody response to recombinant used for typical presentations. One or two weekly dosages of iver- scabies apolipoprotein antigen (Sar s 14) using enzyme-linked im- mectin in some studies, however, is considered less effective than munosorbent assay (ELISA). 22-24 Further, an evolving molecular permethrin topical, but others conclude that although ivermectin’s test using polymerase chain reaction (PCR) amplification of mite response is delayed, its long-term cure rates are superior.30,31 Table DNA from skin scrapings may identify scabies presence but also 1 summarizes the use of these and other current therapies, and Ta- may be useful for determining if treatment has been effective after ble 2 provides levels of evidence.32,33 1 month.25,26 Of course, traditional skin biopsy may also display classic diagnostic features, such as scabies mites, eggs (or eggshell ‘pigtails’), or scybala in the stratum corneum and granulosum, spongiosis near a burrowed female mite, and an eosinophilic and lympho- cytic dermal infiltrate.27 In addition, there are instances where skin biopsy with direct immunofluorescence of perilesional skin for eruptions resembling autoimmune blistering disease may also be falsely positive in scabies infestations, perhaps relating to an overlapping immune response and the aforementioned risk of pemphigoid development in some patients.28 Polarized light microscopy may also be helpful for these biopsy specimens, in that the outer sheath of scabies spines, scybala, and at times the mite gut are all polarizable.29

Therapeutics There is no consensus regarding which topical, systemic, and environmental eradication modalities are most efficacious for scabies management. The range of treatment strategies reflect geographic, economic, and feasibility concerns as well as patient age, comorbidities, and medication resistance and toxicities. Most consider permethrin 5% as the most safe and effective first-line therapy, n Figure 2. Reflectance confocal microscopy image of scabies- with 2 topical applications one week apart as the most-utilized reg- Sarcoptes scabiei mites (asterisks), with their eggs (thin arrows) imen. Oral ivermectin 200 µg/kg is often employed in crusted sca- and droppings (thick arrows). This material is reproduced with 21 bies and in mass treatment efforts, but it is also being increasingly permission of John Wiley & Sons, Inc.

Vol. 33, September 2014, Seminars in Cutaneous Medicine and Surgery 107 n n n Scabies

n Table 1. Drugs commonly used to treat scabies

Treatment Dosage Treatment Contraindication Advantages Disadvantages Comments Regimen

Permethrin 5% cream Rinsed off Effective, well Itching and Second after 8-12 hrs tolerated, safe stinging on application application often routinely prescribed 1 week after the first application Lindane 1% lotion or Rinsed off Pregnant women, Effective, Cramps, dizziness, Withdrawn in cream after 6 hrs infants, seizure inexpensive seizures in the European disorders children Union because of neurotoxicity concerns Benzyl 25% Rinsed off after Pregnant women Effective, Can cause Not currently benzoate ointment 24 hrs (once or and infants (limit inexpensive severe skin available several times) duration of use to irritation in Canada, 12 hrs) approved in Europe Esdépallétrine 0.6% aerosol Rinsed off after People with (bioallethrin) 12 hrs asthma Crotamiton 10% Rinsed off Well tolerated, Questionable Not available in ointment after 24 hrs safe for infants efficacy Canada, often and then used on scabies reapplied for nodules in an additional children 24 hrs Precipitated 2%-10% Rinsed off after Safe for infants, Questionable sulfur precipitate 24 hrs and pregnant and efficacy, skin in petroleum then reapplied breastfeeding irritation base every 24 hrs women for the next 2 days (with a bath taken between each application) Ivermectin Pills 200 µg/kg Children <15 Good patient Expensive Not approved in repeated on kg; pregnant or compliance many countries day 14 breastfeeding women Reproduced with permission from Olivier Chosidow, MD, PhD32

Ivermectin may not be available or licensed for scabies in some definition and timeline for cure are not consistent across studies.38,39 countries, and it is not preferred in pregnant or lactating women (in Other evolving therapies include moxidectin, a veterinary oral which precipitated sulfur or permethrin topicals are now recommend- acaricide with a longer half-life than ivermectin (4 days vs 18 ed) or in patients under 15 kg, although recent evidence suggests that hours), which may provide more effective single-dosage therapy.40 it may be safe for smaller children.34,35 In recalcitrant crusted scabies Herbal newcomers for scabies managment include tea tree oil, patients, it has recently been shown that weekly dosage regimens (in clove oil, neem oil, and aloe vera, which all show some in vitro one case 7 doses) of ivermectin until clinical clearance is effective, as acaricidal activity but no convincing safety and efficacy data, de- is pretreatment of crusted plaques with surgical debridement.36,37 marcating their use as adjunctive.31 In recent reports, topical iver- Recently elucidated resistance mechanisms to these common mectin may be used as an alternative to permethrin. Also, topical therapies are likely mediated by sodium channel mutations for calcineurin inhibitors may be effective in nodular scabies, although permethrin, P-glycoprotein-mediated efflux for ivermectin, and in- these agents may perhaps promote local cutaneous immuosuppres- creased activity of metabolic enzymes like cytochrome P450 and sion that could incite crusted scabies in vulnerable patients.41-44 glutathione S-transferases for both of these medications. However, some studies suggest that combined topical and/or oral therapy The future regimens may synergistically surmount these pathways. Rates of The International Alliance for the Control of Scabies was founded in resistance vary, but this is likely because clinical and laboratory November 2012 and is committed to worldwide scabies eradication,

108 Seminars in Cutaneous Medicine and Surgery, Vol. 33, September 2014 L. L. Rosamilia

2013]. J Eur Acad Dermatol Venereol. doi: 10.1111/jdv.12099. n 12. Chung SD, Lin HC, Wang KH. Increased risk of pemphigoid following scabies: a Table 2. Scabies treatment population-based matched-cohort study [published online ahead of print March 18, 2013]. J Eur Acad Dermatol Venereol. doi: 10.1111/jdv.12132. 13. Jacks SK, Lewis EA, Witman PM. The curette prep: a modification of the traditional scabies preparation. Pediatr Dermatol. 2012;29(4):544-545. Medical treatment of scabies, level of evidence 14. Leung V, Miller M. Detection of scabies: a systematic review of diagnostic measures. Can J Infect Dis Med Microbiol. 2011;22(4):143-146. Topical 15. Dupuy A, Dehen L, Bourrat E, et al. Accuracy of standard dermoscopy for diagnosing n Permethrin 5%a scabies. J Am Acad Dermatol. 2007;56(1):53-62. 16. Park JH, Jim CW, Kim SS. The diagnostic accuracy of dermoscopy for scabies. Ann n Precipitated sulfur 2–10% in petrolatumb Dermatol. 2012;24(2):194-199. 17. Griffin JR, Newman CC. Clinical, dermatoscopic, and microscopic findings of infesta- n a Lindane (gamma benzene hexachloride 1%) tion with Sarcoptes Scabiei var hominis. Mayo Clin Proc. 2011;86(9):e47. n Benzyl benzoate 10–25%a 18. Fox G. Diagnosis of scabies by dermoscopy. BMJ Case Rep. 2009;2009. 19. Cinotti E, Perrot J, Labeille B, Cambazard F. Diagnosis of scabies by high-magnifica- n Monosulfiram 5–25%c tion dermoscopy: the “delta-wing jet” appearance of Sarcoptes scabiei. Ann Dermatol Venereol. 201;140(11):722-23 n a Crotamiton 10% 20. Turan E, Erdemir AT, Gurel MS, Basaran YK. The detection of Sarcoptes scabiei in n Malathion 0.5%c human skin by in vivo confocal microscopy. Eur J Dermatol. 2011;21(6):1004-1005. 21. Cinotti E, Perrot JL, Labeille B, et al. Reflectance confocal microscopy for quanti- n Esdepallethrin 0.63%c fication of Sarcoptes scabiei in Norwegian scabies. J Eur Acad Dermatol Venereol. 2013;27(2):e176-e178. c n Ivermectin 1% 22. Rampton M, Walton SF, Holt DC, et al. Antibody responses to Sarcoptes scabiei apoli- Oral poprotein in a porcine model: relevance to immunodiagnosis of recent infection. PLoS One. 2013;8(6):e65354. n Ivermectina 23. Jayaraj R, Hales B, Viberg L, et al. A diagnostic test for scabies: IgE specificity for a recombinant allergen of Sarcoptes scabiei. Diagn Microbiol Infect Dis. 2011;71(4):403- aGood quality patient-oriented evidence. 407. bLimited quality patient-oriented evidence. 24. Mounsey K, McCarthy J, Walton SF. Scratching the itch: new tools to advance under- cO ther evidence including: consensus guidelines, extrapolations from standing of scabies. Trends Parasitol. 2013;29(1):35-42. bench research, opinion, or case studies. 25. Fukuyama S, Nishimura T, Yotsumoto H, et al. Diagnostic usefulness of a nested poly- Reprinted with permission from Maria Hicks, MD33 merase chain reaction assay for detecting Sarcoptes scabiei DNA in skin scrapings from clinically suspected scabies. Br J Dermatol. 2010;163(4):892-894. 8 advocacy, and research. It is comprised of clinicians from high- 26. Naz S, Rizvi DA, Javaid A, Ismail M, Chaudhry FF. Validation of PCR assay for prevalence areas, including public health physicians, policy makers, identification of Sarcoptes Scabiei var. hominis.Iran J Parasitol. 2013;8(3):437-440. and researchers.8 In recent years, a group of 167 parasitologists from 27. Reinig EF, Albertson D, Sarma D. Pink pigtail on skin biopsy: what is your diagnosis? Dermatol Online J. 2011;17(1):12 88 countries called the Sarcoptes World Molecular Network was 28. Miller DD, Bhawan J. Bullous tinea pedis with direct immunofluorescence positiv- formed which aims to integrate and optimize molecular and clinical ity: when is a positive result not autoimmune bullous disease? Am J Dermatopathol. research, epidemiology, and control efforts for this disease in hu- 2013;35(5):587-594. 45 29. Foo CW, Florell SR, Bowen AR. Polarizable elements in scabies infestation: a clue to mans and animals. In the throes of a decade where many genomes, diagnosis. J Cutan Pathol. 2013;40(1):6-10. including that of Sarcoptes scabiei, are being sequenced, these col- 30. Mounsey KE, McCarthy JS. Treatment and control of scabies. Curr Opin Infect Dis. laborations and innovations help to mount a robust, molecularly 2013;26(2):133-139. 31. Strong M, Johnstone P. Interventions for treating scabies. Cochrane Database Syst specific, and geography-germane response to a global public health Rev. 2007;(3):CD000320 burden that enters any clinician’s office on any given week. 32. Monsel G, Chosidow O. Management of scabies. Skin Therapy Lett. 2012;17(3):1-4. 33. Hicks M, Elston DM. Scabies. Dermatol Ther. 2009;22(4):279-292. 34. Mytton OT, McGready R, Lee SJ, et al. Safety of benzyl benzoate and permethrin in References pregnancy: a retrospective matched cohort study. BJOG. 2007;114(5):582-587. 1. Fuller LC. Epidemiology of scabies. Curr Opin Infect Dis. 2013;26(2):123-126. 35. Bécourt C, Marguet C, Balguerie X, Joly P. Treatment of scabies with oral iver- 2. Cölgeçen Özel E, Ertaş R, Utaş S, Kontaş O. Scabies mimicking mastocytosis in two mectin in 15 infants: a retrospective study on tolerance and efficacy. Br J Dermatol. infants. Turk J Pediatr. 2013;55(5):533-535. 2013;169(4):931-933. 3. Hossain D. Atypical scabies presenting as annular patches. Pediatr Dermatol. 2012 36. Ortega-Loayza AG, McCall CO, Nunley JR. Crusted scabies and multiple dosages of Sep 12 (Epub ahead of print). ivermectin. J Drugs Dermatol. 2013;12(5):584-585. 4. Gutte RM. Bullous scabies in an adult. A case report with review of literature. Indian 37. Maghrabi MM, Lum S, Joba AT, Meier MJ, Holmbeck RJ, Kennedy K. Norwegian Dermatol Online J. 2013;4(4):311-313. crusted scabies: an unusual case presentation. J Foot Ankle Surg. 2014;53(1):62-66. 5. Roxana Stan T, Piaserico S, Bordignon M, Salmaso R, Zattra E, Alaibac M. Bullous 38. Mounsey KE, Pasay CJ, Arlian LG, et al. Increased transcription of glutathione S- scabies simulating pemphigoid. J Cutan Med Surg. 2011;15(1):55-57. transferases in acaricide exposed scabies mites. Parasit Vectors. 2010;3:43. 6. Al Aboud K, Al Aboud D. Multiple lesions of granuloma annulare on the hand in a 39. Pasay C, Arlian L, Morgan M, et al. High-resolution melt analysis for the detection of patient with scabies. Clin Cosmet Investig Dermatol. 2011;4:131-132. a mutation associated with permethrin resistance in a population of scabies mites. Met 7. Kassardjian M, Frederickson J, Griffith J, Shitabata P, Horowitz D. Elastosis perforans Vet Entomol. 2008;22(1):82-88. serpiginosa in association with scabies mite. J Clin Aesthet Dermatol. 2013;6(10):36- 40. Astiz S, Legaz-Huidobro E, Mottier L. Efficacy of long-acting moxidectin against 40. sarcoptic mange in naturally infested sheep. Vet Rec. 2011;169(24):637. 8. Engelman D, Kiang K, Chosidow O, et al; Members of the International Alliance for 41. Goldust M, Rezaee E, Raghifar R, Hemayat S. Treatment of scabies: topical ivermec- the Control of Scabies. Toward the global control of human scabies: introducing the In- tin 1% vs. permethrin 2.5% cream. Ann Parasitol. 2013;59(2):79-84. ternational Alliance for the Control of Scabies. PLoS Negl Trop Dis. 2013;7(8):e2167. 42. Mittal A, Garg A, Agarwal N, Gupta L, Khare A. Treatment of nodular scabies with 9. Fischer K, Holt D, Currie B, Kemp D. Scabies: important clinical consequences ex- topical tacrolimus. Indian Dermatol Online J. 2013;4(1):52-53. plained by new molecular studies. Adv Parasitol. 2012;79:339-373. 43. Almeida H. Treatment of steroid-resistant nodular scabies with topical pimecrolimus. 10. Cote NM, Jaworski DC, Wasala NB, Morgan MS, Arlian LG. Identification and ex- J Am Acad Dermatol. 2005;53(2):357-358. pression macrophage migration inhibitory factor in Sarcoptes scabiei. Exp Parasitol. 44. Ruiz-Maldonado R. Pimecrolimus-related crusted scabies in an infant. Pediatr Der- 2013;135(1):175-181. matol. 2006;23(3):299-300. 11. Chung SD, Wang KH, Huang CC, Lin HC. Scabies increased the risk of chronic kid- 45. Alasaad S, Walton S, Rossi L, et al; Sarcoptes-World Molecular Network (S-WMN): ney disease: a 5-year follow-up study [published online ahead of print February 1, integrating research on scabies. Int J Infect Dis. 2011;15(5):e294-e297.

Vol. 33, September 2014, Seminars in Cutaneous Medicine and Surgery 109 Dermatoses associated with mites other than Sarcoptes Kimberly M. Ken, BA; Solomon C. Shockman, MD; Melissa Sirichotiratana, MD; Megan P. Lent, MD; and Morgan L. Wilson, DVM, MD

n Abstract Mites are arthropods of the subclass Acari (Acarina). Al- though Sarcoptes is the mite most commonly recognized as a cause of human skin disease in the United States, numerous other mite-associated dermatoses have been described, and merit familiarity on the part of physicians treating skin disease. This review discusses several non- scabies mites and their associated diseases, including Demodex, chiggers, Cheyletiella, bird mites, grain itch, oak leaf itch, grocer’s itch, tropical rat mite, snake mite, and Psoroptes. Semin Cutan Med Surg 33:110-115 © 2014 Frontline Medi- cal Communications

ites are arthropods of the class Arachnida and subclass Acari (Acarina), with life cycles inclusive of eggs, lar- Mvae, nymphs, and adults. In general, adult mites and nymphs have eight legs, while larval forms have six. Although Sarcoptes scabiei (scabies) is the mite best recognized as a cause n Figure 1. Demodex mite (potassium hydroxide preparation of of cutaneous pathology in humans, numerous others have been a skin scraping) occasionally implicated, and warrant familiarity on the part of physicians. portion of the hair follicle.1,4,5 Demodex brevis is slightly shorter, has a pointed posterior segment, and is found in sebaceous and Demodicosis meibomian glands.4,6 There are over 100 species within the genus Demodex, with many Proposed mechanisms of Demodex pathogenesis include mite residing as commensals or ectoparasites in the skin and piloseba- blockage of hair follicles and sebaceous ducts leading to reactive ceous units of a variety of mammalian species.1 Demodicosis is the hyperkeratosis, stimulation of host immune reactions in response to name given to disease related to Demodex mites. The most well- the mites and their waste, foreign body granulomatous reaction to known example is demodectic mange, which occurs in dogs in as- the chitinous skeleton of the mite, and mites serving as a vector for sociation with increased numbers of Demodex canis, often in the bacteria.7 Since Demodex is part of the normal human skin fauna, setting of impaired immunity, and presents with alopecia, scale, it can be difficult to determine its significance when identified in and dermatitis.2 This and other forms of demodicosis in animals the setting of skin disease. Potassium hydroxide (KOH) preparations are not known to be transmissible to humans. Although well-estab- can be used to visualize mites (Figure 1), but the number expected lished in dogs, the role of Demodex in human skin disease has been in normal skin relative to diseased skin is unclear. Histopathologi- difficult to clearly define. cally, reported cases of demodicosis have shown perifollicular and Two species of Demodex mites, Demodex folliculorum and De- perivascular lymphohistiocytic infiltrates, neutrophils, and numer- modex brevis, are saprophytes found on normal human skin, and ous Demodex mites in follicular infundibula and within infundibular colonize nearly 100% of humans by adulthood.1,3 Demodex fol- pustules.7 Dermatoscopic findings of demodicosis include whitish liculorum is 0.3-0.4mm in length, and resides in the superficial Demodex tails projecting from follicular ostia and brown plugs sur- part of the follicular infundibulum, where its head faces the deeper rounded by erythematous halos in dilated follicular openings.8 A noninvasive standardized skin-surface biopsy (SSSB) tech- nique has been used to assess the density of mites in demodicosis Department of Internal Medicine, Division of Dermatology,Southern Illinois compared with normal skin.6 A density of greater than 5 mites/ University School of Medicine, Springfield. cm2 in SSSB is considered indicative of demodicosis. In clinical Disclosures: The authors have no conflicts of interest to declare. Correspondence: Morgan Wilson, DVM, MD; Department of Internal practice, the pathogenic role of Demodex is most convincingly Medicine, Division of Dermatology; Southern Illinois University School of supported when patients with disease in Demodex-colonized areas Medicine; PO Box 19644; Springfield, IL 62794-9644. E-mail: mwilson3@ and a high density of Demodex mites are cured with acaricidal siumed.edu treatments.3

110 Seminars in Cutaneous Medicine and Surgery, Vol. 33, September 2014 1085-5629/13$-see front matter © 2014 Frontline Medical Communications DOI: 10.12788/j.sder.0104 K. M. Ken, S. C. Shockman, M. Sirichotiratana, M. P. Lent, and M. L. Wilson

Demodex has been implicated in multiple dermatoses. It has prominent. Lesions have a characteristic distribution, following a been suggested that there is an increased risk in patients older than circumferential pattern in areas where clothing is constrictive, such 50 years, a history of topical steroid use, immunosuppression, or as sock bands and waistbands. Penile and scrotal lesions are also debilitation; however, most reported patients with demodicosis are common. Boys may experience “summer penile syndrome” with in good general health.3,4,9,10 seasonal penile swelling, pruritus, and dysuria.22 Pityriasis folliculorum presents with diffuse faint facial ery- In Asia and islands of the south Pacific and Indian Oceans, mem- thema, burning and itching sensations, and a dry “nutmeg grater” bers of the genus Leptotrombidium may act as vectors for scrub appearance resulting from follicular plugging by scales.11 Primarily typhus (Tsutsugamushi fever) when the causative bacterium Ori- affecting women, pityriasis folliculorum is often preceded by a his- entia tsutsugamushi is passed into the host via the mite’s salivary tory of infrequent use of soap for facial washing together with the secretions. At the site of the larval bite, an eschar forms in the use of heavy creams and make-up.9 majority of primary cases. Other manifestations may include fe- Rosacea-like demodicosis presents very similarly to conven- ver, chills, headache, lymphadenopathy, rash, pneumonitis, and en- tional rosacea, with erythematous papulopustular lesions.7,9 Other cephalitis.23,24 Laboratory data have raised questions as to whether findings include infundibular mite infestation and superficial scale, these mites may also serve as vectors for other viral and bacterial as well as resistance to usual rosacea therapies.9 Granulomatous pathogens; however, the clinical significance of these findings re- rosacea-like eruption, also known as demodicosis gravis, presents mains uncertain.25-27 with dome-shaped papules without observable pustules.7 Histo- Prevention is the optimal defense against chigger bites. Using logically, dermal caseating granulomas with phagocytized mite DEET (N, N diethyl-meta-toluamide) repellent and/or treating remnants are seen.9 clothing with permethrin is effective against various arthropods, Demodex-associated pustular folliculitis has been described as including chiggers.28,29 Wearing clothing treated with permethrin antibiotic-unresponsive folliculitis, with numerous mites in KOH reduces chigger attachments,29 and the repellent effect can last for skin scrapings.12 Perioral dermatitis associated with Demodex in- multiple days and through multiple washings. Products containing festation presents as papulopustular lesions limited to the perioral citronella oil, jojoba oil, tea tree oil, geranium oil, lemon grass oil, areas.4 Demodex abscess has been described as a protracted course and clove oil have also demonstrated efficacy as chigger repel- of confluent erythematous papules, pustules, and deep nodules lents.30,31 Treatment for cutaneous eruptions is aimed at symptom- on the face, with many Demodex mites seen on skin scrapings.13 atic relief with topical antipruritics or topical anesthetics. Potent Other skin diseases that have been described in association with topical corticosteroids may be helpful, but their benefits are de- Demodex are blepharitis, alopecia, and external otitis with chronic layed and may require occlusion. If topical therapy is unsuccessful, pruritus.14,15 intralesional corticosteroids may be effective. There is no standard therapy for human demodicosis. Medica- tions used successfully in case reports have included oral iver- Cheyletiellosis mectin and topical permethrin, selenium sulfide, crotamiton, and Cheyletiella yasguri, C. blakei, and C. parasitovorax are non- metronidazole.4,7,14 burrowing mites that parasitize dogs, cats, and rabbits, respective- ly,32,33 and may cause dermatitis in humans who have contact with Harvest mites (chiggers) Chigger (Figure 2) is an alternate name for larval mites of the family Trombiculidae. Globally, this family comprises many species, which are also known by common names, such as harvest mites, mower’s mites, red bugs, berry bugs, and scrub itch mites.16,17 In North Amer- ica, Trombicula is the primary genus of medical interest. Bites are often sustained during the summer or early autumn. Chiggers abound in moist, grassy or bushy terrain, and may be concentrated in short to long grass transition zones or at the edges of forests.18-20 Female mites lay clusters of eggs on low vegetation or damp ground. Subsequent to hatching, the tiny yellow to red 6-legged larval mite crawls onto vegetation, where it waits for a host to pass by. A variety of mammals, birds, and reptiles are the preferred hosts, however, humans are also readily infested.17,19 Measuring less than 1 millimeter, the larvae often go unnoticed by affected humans. The mite becomes engorged after 1-4 days of feeding19 and drops off to continue maturation into an 8-legged free-living nymph and then an adult. On biting, a chigger penetrates the host’s upper dermis with che- licerae before injecting saliva. The saliva solidifies into a stylostome, or feeding tube, attached to the mouthparts, through which salivary enzymes digest host tissues.21 Initial lesions appear as small papules or wheals which may progress into pustules, vesi- n cles, or bullae. The pruritus is severe, and excoriations are often Figure 2. Harvest mite (chigger). Photo courtesy of Dirk Elston, MD.

Vol. 33, September 2014, Seminars in Cutaneous Medicine and Surgery 111 n n n Dermatoses associated with mites other than Sarcoptes

pigeons, sparrows, starlings, finches, ducks, turkeys, wrens, para- keets, and canaries.36-38 When the preferred avian hosts are absent, humans and other mammals may be infested. D. gallinae mites are less than 1 mm in diameter, and are clinically barely visible as tiny brown to red dots.39 They hide in nests, cracks, and crevices during the day, and attach temporarily to the host bird at night to feed. O. sylviarum, in contrast, spends essen- tially its entire life on the host bird. It is likewise barely visible to the naked eye, and has been described by patients as tiny “black dots” when observed in the household environment.37 Disease in humans occurs in several situations. Commonly, agricultural workers handling infested poultry are affected. Secondly, wild birds often nest on or near window sills, balconies, eaves, rooftops, and attics. When young birds leave the nest, the mites re- maining in the nest will then seek a new host, and may enter homes through windows, air conditioners, or ventilation ducts.37,38 Hu- mans who collect or otherwise intentionally handle bird nests may be directly infested. Bird mites may also parasitize small mam- n Figure 3. Cheyletiella. Photo courtesy of Dirk Elston, MD mals, and gerbils have served as a source for human infestation.38 The dermatitis is non-specific, consisting of widespread pru- these animals. Cheyletiella live in the keratin layer of the epider- ritic papules, often on uncovered areas.40 In contrast to scabies, the mis and consume surface debris and tissue fluids.33 The ova attach eruption often spares the interdigital spaces and genitalia.37 Mites to the host animal’s hair, and are smaller than the average louse nit. have been identified directly on humans in rare cases;41 however, it The adult mites measure approximately 0.4 mm,33 and are barely is more typical that they take a blood meal and then leave the hu- visible to the naked eye as small white specks on the host animal’s man, such that mites are not found during skin examination. Inves- hair or skin, leading to their description as “walking dandruff”. tigation for an environmental reservoir, such as a bird, abandoned Microscopically, they are similar in size to scabies mites, but have nest, or pet rodent, is critical. It is noted that Ornithonyssus spp. a somewhat more elongated body and characteristic hook-shaped are typically found on the host animal, while examination of the accessory mouthparts (Figure 3). host animal’s environment (cages, bedding, nests) is necessary in A history of a recently introduced pet in the household may be a order to identify D. gallinae. Eradication of nests and treatment of clue to the diagnosis. Infested pets may be asymptomatic or have a the environment with an appropriate acaricide is recommended for mild dermatitis, often with dry, white scales on the dorsum of the control of Dermanyssus, whereas treatment of the affected birds back.34 Affected humans may develop a more prominent derma- and/or elimination of exposure to the source birds is necessary for titis, with grouped erythematous, pruritic papules. Occasionally, Ornithonyssus spp.37 When mites are found on humans, topical apical vesicles, bullae or urticarial wheals can be noted.34,35 The permethrin may be of benefit.41 Topical corticosteroids are of vari- rash is commonly found in areas which have been in direct con- able benefit for symptomatic relief. tact with the source animal, such as the chest, abdomen and upper extremities.35 Systemic hypersensitivity to Cheyletiella blakei has been reported, with associated peripheral blood eosinophilia and joint pain.32 Diagnosis involves examination of the source animal by a veterinarian, with identification of Cheyletiella in brushings, scrapings, or acetate tape preparations.34 Treatment of Cheyletiella dermatitis primarily involves acaricidal treatment of the source animal(s) by a veterinarian. As the mites do not establish a sustained infestation in humans, mites are not found on scrapings from affected humans, and acaricidal treatment is typically not necessary, with spontaneous resolution expected within a few weeks of cessation of exposure. Topical anti-pruritic or anti-inflammatory agents can be used symptomatically if needed.

Bird mites Gamasoidosis is the term used for human skin disease caused by bird mites. The avian mites most commonly affecting humans are the chicken mite or red mite (Dermanyssus gallinae), the northern fowl mite (Ornithonyssus sylviarum; Figure 4), and the tropical fowl mite (Ornithonyssus bursa). These mites parasitize chickens n Figure 4. Northern fowl mite (Ornithonyssus sylviarum). Photo and other domestic fowl, as well as wild and pet birds, including courtesy of Dirk Elston, MD.

112 Seminars in Cutaneous Medicine and Surgery, Vol. 33, September 2014 K. M. Ken, S. C. Shockman, M. Sirichotiratana, M. P. Lent, and M. L. Wilson

or felt a bite. An investigation revealed the likely cause to be the oak leaf itch mite (Pyemotes herfsi), which feeds on the larvae of midges found within galls on the leaves of pin oak trees.46 In a subsequent outbreak in Pennsylvania, patients developed pruritic, erythematous papules and plaques (Figure 5) with tiny central vesicles, predominantly on areas of skin not covered by clothing. Affected individuals again lived in proximity to pin oak trees with marginal leaf fold galls containing P. herfsi (Figure 6).47 The oak leaf itch mite, approximately 0.2 mm in length, is difficult to see with the naked eye. Due to its small size, the mites can be carried by the wind, and can pass through window screens. Although oak leaf itch mites may bite humans, they do not establish an ongoing infestation, and spontaneous resolution of lesions is expected. In areas where this mite is recognized as a problem, preventative strategies include use of light-colored, tight-fitting n Figure 5. Pruritic erythematous papules and plaques on the clothing, permethrin-treated clothing, and an application of DEET posterior neck in a patient exposed to Pyemotes herfsi. Photo (N,N-diethyl-meta-toluamide). courtesy of Jennifer Sceppa, MD. Grocer’s itch Mites of several genera are common contaminants of stored cere- Grain itch/ straw itch als, fruits, cheeses, and meat. Dermatitis occurring in individuals Pyemotes ventricosus is responsible for most cases of “grain itch” handling such items has been referred to as “grocer’s itch”. Spe- or “straw itch”. This mite is small (0.16-0.22 mm), and is barely cifically, Carpoglyphus passularum has been reported to cause an visible to the naked eye as a white speck. It is a primarily a parasite eruption of pruritic red papules in a dock worker exposed to in- of insects found on wheat and other grain-producing plants; how- fested figs.48 An irritant contact-like dermatitis has been observed ever, it will attack humans if its normal hosts are in short supply.42 in workers handling cheese contaminated with Tyroglyphus (Ty- It has been found in most of the United States, with most cases of rophagus) mites,49 which are likewise the cause of copra itch,50 and grain itch reported in midwestern or southern states. P. tritici has have resulted in dermatitis after contact with cured ham.51 been reported to cause similar outbreaks in the Middle East.43 Cases of human disease typically occur in agricultural workers Tropical rat mite or others in direct contact with wheat straw or a variety of grains. The tropical rat mite (TRM), Ornithonyssus bacoti, is a hematoph- Within hours of exposure, affected individuals develop pink to red agous external parasite of rodents. The term “tropical” is mislead- wheals surmounted by vesicles, which evolve to pustules.44 The le- ing, as it is found in both tropical and temperate climates, and has sions are intensely pruritic, and often excoriated. Some patients are been identified on all continents other than Antarctica52 as well as severely affected, with 200-300 bites. Associated symptoms can in the majority of the United States.53 The principle hosts are the include fever, headache, vomiting, and lymphadenopathy. Other wild brown rat and black rat, but other rodents will also suffice, arthropod bites, rickettsialpox, and varicella are among the clinical such as mice, hamsters, and gerbils.52,53 When the availability of differential diagnoses. In Europe, pruritic bite reactions have been these hosts decreases, as may occur during rodent extermination observed in the owners of wooden furniture infested with the fur- programs, humans can become an alternative host, leading to epi- niture beetle (Anobium punctatum), the larvae of which are parasit- demics of dermatitis.52 ized by P. ventricosus.45 The mite is difficult to identify on a human, but can often be identified on infested straw or grain. Although the mites donot establish a sustained infestation on human hosts, the eruption may persist if contact with the infested material continues; therefore, elimination of the source material may be necessary. Although infested straw has been successfully treated with pyrethrins and piperonyl butoxide,44 the application of pesticides to grains is limited, as the grain is typically intended for use as a food product. Any mites currently on a human’s skin can be eliminated via use of topical permethrin or other acaricides.

Oak leaf itch In August, 2004, an estimated 54% of the population in one Kansas county was afflicted with an eruption of pruritic papules, which occurred after outdoor activity and resolved spontaneously over several days. Although skin lesions had an appearance clinically n Figure 6. Pyemotes herfsi gravid females on the leaf of a pin consistent with arthropod bite reactions, most patients had not seen oak (Quercus palustris). Photo courtesy of Steve Jacobs, MS.

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The adult mite measures 0.6 mm to 1.1 mm.54 The mites feed 4. Weingartner JS, Allen PS. What is your diagnosis? Demodex folliculitis. Cutis. 2012;90(2):62, 65-66, 69. briefly at night, and hide in dark cracks and crevices during the 5. Sattler EC, Maier T, Hoffmann VS, Hegyi J, Ruzicka T, Berking C. Noninvasive day. The bite is not immediately recognized by the host, and can in vivo detection and quantification of Demodex mites by confocal laser scanning lead to dermatitis, presumably due to a reaction to the saliva and microscopy. Br J Dermatol. 2012;167(5):1042-1047. mouth parts. The rash typically consists of pruritic, erythematous 6. Forton F, Seys B. Density of Demodex folliculorum in rosacea: a case-control study using standardized skin-surface biopsy. Br J Dermatol. 1993;128(6):650-659. 52 papules or wheals, often on the back, extremities, and waistline. 7. Hsu CK, Hsu MM, Lee JY. Demodicosis: a clinicopathological study. J Am Acad Diagnosis of TRM dermatitis requires a thorough inspection of the Dermatol. 2009;60(3):453-462. environment for host rodents and mites. Since the mites spend the 8. Segal R, Mimouni D, Feuerman H, Pagovitz O, David M. Dermoscopy as a diagnostic tool in demodicidosis. Int J Dermatol. 2010;49(9):1018-1023. majority of their time in the environment, they will not necessar- 9. Baima B, Sticherling M. Demodicidosis revisited. Acta Derm Venereol. ily be found on the host animal, and are rarely found on affected 2002;82(1):3-6. humans. Treatment involves extermination of the mites, as well 10. Dolenc-Voljc M, Pohar M, Lunder T. Density of Demodex folliculorum in perioral as control of the associated rodent host population. Any small dermatitis. Acta Derm Venereol. 2005;85(3):211-215. 11. Ayres S Jr., Ayres S 3rd. Demodectic eruptions (demodicidosis) in the human. 30 mammalian pets should be examined by a veterinarian and treated years’ experience with 2 commonly unrecognized entities: pityriasis folliculorum appropriately.52 Since the mites do not establish a sustained infes- (Demodex) and acne rosacea (Demodex type). Arch Dermatol. 1961;83:816-827. tation in humans, acaricidal treatment of humans is typically not 12. Purcell SM, Hayes TJ, Dixon SL. Pustular folliculitis associated with Demodex folliculorum. J Am Acad Dermatol. 1986;15(5 Pt 2):1159-1162. necessary. Topical corticosteroids may be used for symptomatic 13. Schaller M, Sander CA, Plewig G. Demodex abscesses: clinical and therapeutic treatment of the dermatitis. challenges. J Am Acad Dermatol. 2003;49(5 Suppl):S272-S274. 14. Elston DM. Demodex mites as a cause of human disease. Cutis. 2005;76(5):294- Snake mite 296. 15. Post CF, Juhlin E. DEMODEX FOLLICULORUM AND BLEPHARITIS. Arch The snake mite (Ophionyssus natricis) is a 0.6-1.3 mm hematopha- Dermatol. 1963;88:298-302. gus parasite of snakes and lizards, and has been reported to cause 16. Millikan LE. Mite infestations other than scabies. Semin Dermatol. 1993;12(1):46- a papular and vesicular eruption in a family with an infested pet 52. python. Dusting of the snake and its immediate environment with 17. Elston DM. What’s eating you? Chiggers. Cutis. 2006;77(6):350-352. 18. Kuo CC, Huang JL, Shu PY, Lee PL, Kelt DA, Wang HC. Cascading effect of eco- 55 pyrethrum powder was effective in ending the infestation. nomic globalization on human risks of scrub typhus and tick-borne rickettsial diseases. Ecol Appl. 2012;22(6):1803-1816. Psoroptes 19. Yates VM. Harvest mites--a present from the Lake District. Clin Exp Dermatol. 1991;16(4):277-278. Psoroptes ovis is a non-burrowing ectoparasite of sheep, which 20. Clopton RE, Gold RE. Distribution and seasonal and diurnal activity patterns of Eu- causes psoroptic mange (sheep scab), characterized by crusts, alo- trombicula alfreddugesi (Acari: Trombiculidae) in a forest edge ecosystem. J Med pecia, and emaciation in affected animals.56 The disease is believed Entomol. 1993;30(1):47-53. to be eradicated in some nations, including the US, Canada, Aus- 21. Shatrov AB. Stylostome formation in trombiculid mites (Acariformes: Trombiculi- dae). Exp Appl Acarol. 2009;49(4):261-280. tralia, and New Zealand. There are rare reports of human infesta- 22. Smith GA, Sharma V, Knapp JF, Shields BJ. The summer penile syndrome: seasonal tion in individuals who have contact with sheep, often presenting acute hypersensitivity reaction caused by chigger bites on the penis. Pediatr Emer as dermatitis on the upper or lower extremities.57 Source animals Care. 1998;14(2):116-118. 23. Rapsang AG, Bhattacharyya P. Scrub typhus. Indian J Anaesth. 2013;57(2):127- should be treated by a veterinarian. The optimal therapy for hu- 134. mans is uncertain, although application of a topical acaricide such 24. Han DK, Baek HJ, Shin MG, Kim JW, Kook H, Hwang TJ. Scrub typhus-associated as 5% permethrin cream has been recommended.58 severe hemophagocytic lymphohistiocytosis with encephalomyelitis leading to per- manent sequelae: a case report and review of the literature. J Pediatr Hematol On- col. 2012;34(7):531-533. Conclusion 25. Wu G, Zhang Y, Guo H, Jiang K, Zhang J, Gan Y. The role of Leptotrombidium scu- Patients with papular urticaria are a common clinical challenge, tellare in the transmission of human diseases. Chin Med J (Engl). 1996;109(9):670- particularly when the history does not reveal a known source of 673. arthropod bites. In addition to common culprits such as fleas, 26. Literak I, Stekolnikov AA, Sychra O, Dubska L, Taragelova V. Larvae of chigger mites Neotrombicula spp. (Acari: Trombiculidae) exhibited Borrelia but no Ana- mosquitoes, and bed bugs, it is useful to consider infestation with plasma infections: a field study including birds from the Czech Carpathians as hosts non-scabies mites. Inquiry regarding occupational and environ- of chiggers. Exp App Acarol. 2008;44(4):307-314. mental factors is critical, and in many cases, the responsible mite 27. Kampen H, Schöler A, Metzen M, et al. Neotrombicula autumnalis (Acari, Trombi- culidae) as a vector for Borrelia burgdorferi sensu lato? Exp App Acarol. 2004;33(1- is found not on the human patient, but rather in the environment or 2):93-102. on domestic or wild animals in the patient’s surroundings. When 28. Frances SP. Response of a chigger, Eutrombicula hirsti (Acari: Trombiculidae) to re- a source of exposure can be identified, elimination or reduction pellent and toxicant compounds in the laboratory. J Med Entomol. 1994;31(4):628- of exposure is often the key step in management of the clinical 630. 29. Breeden GC, Schreck CE, Sorensen AL. Permethrin as a clothing treatment for per- disease. Finally, when patients present with papulopustular facial sonal protection against chigger mites (Acarina: Trombiculidae). Am J Trop Med eruptions unresponsive to conventional rosacea therapy, consider- Hyg. 1982;31(3 Pt 1):589-592. ation of demodicosis may be warranted. 30. Hanifah AL, Ismail SH, Ming HT. Laboratory evaluation of four commercial repellents against larval Leptotrombidium deliense (Acari: Trombiculidae). Southeast Asian J Trop Med Public Health. 2010;41(5):1082-1087. References 31. Eamsobhana P, Yoolek A, Kongkaew W, et al. Laboratory evaluation of aromatic 1. Lacey N, Kavanagh K, Tseng SC. Under the lash: Demodex mites in human dis- essential oils from thirteen plant species as candidate repellents against Leptotrom- eases. Biochem (London). 2009;31(4):2-6. bidium chiggers (Acari: Trombiculidae), the vector of scrub typhus. Exp App Ac- 2. Elston DM, Lawler KB, Iddins BO. What’s eating you? Demodex folliculorum. Cu- arol. 2009;47(3):257-262. tis. 2001;68:93-94. 32. Dobrosavljevic DD, Popovic ND, Radovanovic SS. Systemic manifestations of 3. Forton F, Germaux MA, Brasseur T, et al. Demodicosis and rosacea: epidemiol- Cheyletiella infestation in man. Int J Dermatol. 2007;46(4):397-399. ogy and significance in daily dermatologic practice. J Am Acad of Dermatol. 33. Angarano DW, Parish LC. Comparative dermatology: parasitic disorders. Clin Der- 2005;52(1):74-87. matol. 1994;12(4):543-550.

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34. Wagner R, Stallmeister N. Cheyletiella dermatitis in humans, dogs and cats. Br J Assoc. 1952;150(16):1575-1579. Dermatol. 2000;143(5):1110-1112. 45. Del Giudice P, Blanc-Amrane V, Bahadoran P, et al. Pyemotes ventricosus dermati- 35. Cvancara JL, Elston DM. Bullous eruption in a patient with systemic lupus ery- tis, southeastern France. Emerg Infect Dis. 2008;14(11):1759-1761. thematosus: mite dermatitis caused by Cheyletiella blakei. J Am Acad Dermatol. 46. Centers for Disease Control and Prevention (CDC). Outbreak of pruritic rashes asso- 1997;37(2 Pt 1):265-267. ciated with mites--Kansas, 2004. MMWR. Morb Mortal Wkly Rep. 2005;54(38):952- 36. Schulze KE, Cohen PR. Dove-associated gamasoidosis: a case of avian mite derma- 955. titis. J Am Acad Dermatol. 1994;30(2 Pt 1):278-280. 47. Sceppa JA, Lee YH, Jacobs SB, Adams DR. What’s eating you? Oak leaf itch mite 37. Orton DI, Warren LJ, Wilkinson JD. Avian mite dermatitis. Clin Exp Dermatol. (Pyemotes herfsi). Cutis. 2011;88(3):114-116. 2000;25(2):129-131. 48. O’Donovan WJ. Carpoglyphus Passularum causing Dermatitis. Proc R Soc Med. 38. Lucky AW, Sayers C, Argus JD, Lucky A. Avian mite bites acquired from a new 1920;13(Dermatol Sect):150-151. source--pet gerbils: report of 2 cases and review of the literature. Arch Dermatol. 49. Dowling GB, Thomas EW. Cheese Itch: Contact Dermatitis due to Mite-infested 2001;137(2):167-170. Cheese Dust. Br Med J. 1942;2(4270):543. 39. Collgros H, Iglesias-Sancho M, Aldunce MJ, et al. Dermanyssus gallinae (chick- 50. Castellani A. Note on Copra Itch. Proc R Soc Med. 1913;6(Dermatol Sect):28-29. en mite): an underdiagnosed environmental infestation. Clin Exp Dermatol. 51. Estévez MD. Occupational contact urticaria-dermatitis by Tyrophagus putrescen- 2013;38(4):374-377. tiae. Contact Dermatitis. 2006;55(5):308-309. 40. Baselga E, Drolet BA, Esterly NB. Avian mite dermatitis. Pediatrics. 52. Beck W. Occurrence of a house-infesting Tropical rat mite (Ornithonyssus bacoti) 1996;97(5):743-745. on murides and human beings. Travel Med Infect Dis. 2008;6(4):245-249. 41. Dogramaci AC, Culha G, Ozcelik S. Dermanyssus gallinae infestation: an un- 53. Fishman HC. Rat mite dermatitis. Cutis. 1988;42(5):414-416. usual cause of scalp pruritus treated with permethrin shampoo. J Dermatol Treat. 54. Beck W, Fölster-Holst R. Tropical rat mites (Ornithonyssus bacoti) - serious ecto- 2010;21(5):319-321. parasites [in English, German]. J Dtsch Dermatol Ges. 2009;7(8):667-670. 42. Centers for Disease Control (CDC). Occupational dermatitis associated with grain 55. Schultz H. Human infestation by Ophionyssus natricis snake mite. Br J Dermatol. itch mites - Texas. MMWR. Morb Mortal Wkly Rep. 1981;30(47):590-592. 1975;93(6):695-697. 43. Rosen S, Yeruham I, Braverman Y. Dermatitis in humans associated with the mites 56. Losson BJ. Sheep psoroptic mange: an update. Vet Parasitol. 2012;189(1):39-43. Pyemotes tritici, Dermanyssus gallinae, Ornithonyssus bacoti and Androlaelaps 57. Mazyad SA, Sanad EM, Morsy TA. Two types of scab mites infesting man and casalis in Israel. Med Vet Entomol. 2002;16(4):442-444. sheep in North Sinai. J Egypt Soc Parasitol. 2001;31(1):213-222. 44. Booth BH, Jones RW. Epidemiological and clinical study of grain itch. J Am Med 58. Elston DM. What’s eating you? Psoroptes mites. Cutis. 2006;77(5):283-284.

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