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Lily Kim
HUMBIO 153
Dr. D. Scott Smith
March 9, 2012
Background Document for Scabies Final Project
<Scabies>
- Source: "Scabies." PubMed Health. 4 Oct. 2010. Web.
<http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001833/>.
The caveat to the direct transmission is that the disease can be transmitted between people who
sleep in same bed (From the personal interaction with Dr. To Shwayder, Director Pediatric
Dermatology, Henry Ford Hospital)
<Scabies Life Cycle>
-Source: Currie, Bart J., and James S. McCarthy. "Permethrin and Ivermectin for Scabies." The
New England Journal of Medicine 362 (2010). Print.
Scabies life cycle begins with mating. The male and female adult mites burrow under the
epidermis of the human host and once they mate, the female adult lays eggs (2-3 per day). The
egg hatches, releasing larvae (2-3 days). The larvae go through lymph stages and ultimately
mature into adults (10-17 days). The cycle then repeats.
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When the scabies burrow into the skin, skin lesions result. Because people can be hypersensitive
against the excretions of mites, leading to a more serious, widespread inflammatory responses in
skin.
<Vector Biology>
-Source: Andersen, B. "Outbreak of Scabies in Norwegian Nursing Homes and Home Care
Patients: Control and Prevention." Journal of Hospital Infection 45.2 (2000): 160-64. Print.
<Diagnosis>
-Source: Goldstein, Adam O., and Beth G. Goldstein. "Scabies." UpToDate. Web. 08 Mar. 2012.
<http://www.uptodate.com/contents/scabies?source=search_result>.
<Symptoms>
-Source: Dr. Tor Shwayder, Director Pediatric Dermatology, Henry Ford Hospital
Because itching might not start one month after infection, asking whether people itch or not does
not always help for diagnosis. This is possibly because there have to be a lot of scabies in order
to cause immune response in humans.
-Source: Hay R, Steer AC, Engelman D, Walton S. Scabies in the developing world. Clin
Microbiol Infect 2012; 18 (in press).
Secondary bacterial infection can be caused by group A streptococci and/or Staphylococcus
aureus. This can lead to nephritis, rheumatic fever, and sepsis.
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<Crusted Scabies>
- Source: Towersey, Loan. "Dermoscopy of Norwegian Scabies in a Patient with Acquired
Immunodeficiency Syndrome." An. Bras. Dermatol. 85.2 (2010). Print.
<History>
- Source: Roncalli, R.a. "The History of Scabies in Veterinary and Human Medicine from
Biblical to Modern times." Veterinary Parasitology 25.2 (1987): 193-98. Print.
- Source: GREEN, MANFRED S. "EPIDEMIOLOGY OF SCABIES." Epidemiologic Reviews
11 (1989). Print.
Historically, scabies posed as a major threat during military campaigns such as during the
Napoleonic Wars when the disease was named as “seven year itch.” It is now an obsolete term.
Cropley, T. "The “army Itch:” A Dermatological Mystery of the American Civil War." Journal of
the American Academy of Dermatology 55.2 (2006): 302-08. Print.
During the American Civil War, the Northern soldiers coined the term “camp itch” to refer to the
debilitating itchiness caused by scabies. The itchiness was one of the difficulties that the soldiers
faced during the war, which is argued to have decreased morale of the army as well. After the
war, the so-called army itch problem went away rapidly thanks to the use of scabicides and
public sanitation.
<Epidemiology>
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- Source: Board, A.D.A.M. Editorial. "Causes, Incidence, and Risk Factors." Scabies. U.S.
National Library of Medicine, 18 Nov. 0000. Web.
<http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001833/.>.
<Risk Factors>
- Source:
1. Clin Microbiol Rev. 2007 Apr;20(2):268-79.
Problems in diagnosing scabies, a global disease in human and animal populations.
Walton SF, Currie BJ.
2. "Scabies Management." Canadian Paediatric Society: Promoting Child Health & Safety.
Web. <http://www.cps.ca/english/statements/ii/ii01-01.htm>.
3. Alexander JO’D. Arthropods and Human Skin. Springer-Verlag, Berlin, Germany 227-292;
1984.
Here, poverty and overcrowding are identified as the two main factors responsible for the
spread of the disease.
<Scabies as a Humanitarian Crisis>
-Source: Tor Shwayder MD, FAAP, FAAD, Director Pediatric Dermatology, Henry Ford
Hospital
Dr. Shwayder says that poverty increases incidence and that in some areas, the entire
population is infected.
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<Scabies During Ugadan Civil War>
-Source: Akello, Grace. "Wartime Children’s Suffering and Quests for Therapy in Northern
Uganda." African Studies Centre African Studies Collection 25 (2010). Print.
The military conflict began in 1986. The study was conducted between 2004-2005. In 2004,
northern Uganda has been a conflict zone for about 20 years. According to the World Food
Programme in 2003, it was estimated that around 800,000 people were internally displaced to
avoid the armed conflict in Gulu, Kitgum, and Pader in northen Uganda. The majority of them
were women and children. Children in this study slept at night commuters’ shelters and some
attended displaced primary schools.
<Treatment and Interventions>
-Source: Akello, Grace. "Wartime Children’s Suffering and Quests for Therapy in Northern
Uganda." African Studies Centre African Studies Collection 25 (2010). Print.
Medecins Sans Frontiers implemented a cure-based approach in which the health workers
guided the patients to take a bath with the medicated soap, which was provided to them. After
that, the patients were smeared with Benzyl Benzoate ointment. This method proved to be
extremely effective in decreasing prevalence of scabies among children. But the method also has
limitations because it is based on a one-time only cure and does not address the root cause or
other more upstream, environmental factors of the epidemic.
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<Diagnosis>
-Source: Tor Shwayder MD, FAAP, FAAD, Director Pediatric Dermatology, Henry Ford
Hospital
According to Dr. Shwayder, lesions can also appear in faces unlike what the old literature
says.
<Burrows for Diagnosis>
-Source: Tor Shwayder MD, FAAP, FAAD, Director Pediatric Dermatology, Henry Ford
Hospital
It is not always easy to possible to spot burrows, but they do increase the likelihood of a
person having the disease. Instead of the diagnosis based on clinical presentation, a physician can
use diagnostic tests such as skin scraping, dermoscopy, and the adhesive tape test to obtain more
accurate results. but negative results do not exclude scabies. Thus, a therapeutic trial with an
anti-scabietic medication may be helpful in difficult cases.
<Diagnostic Tests>
-Source: Tor Shwayder MD, FAAP, FAAD, Director Pediatric Dermatology, Henry Ford
Hospital
<Treatment>
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-Source: "Evaluation of the Commonest Site, Demographic Profile and Most Effective Therapy
in Scabies Das S, Chatterjee T, Banerji G, Biswas I - Indian J Dermatol." Indian Journal of
Dermatology: Free Full Text Articles from Indian J Dermatol. Web. 2006. <http://www.eijd.org/article.asp?issn=00195154;year=2006;volume=51;issue=3;spage=186;epage=188;aulast=Das>.
In this study, 200 Indian scabies patients were divided into four groups, and each group
received a different type of treatment. Pregnant women and children less than 2 years old were
not allowed to participate in the study. Each person was randomly assigned to one of the four
groups. Each group consisted of 50 people. People assigned to Group 1 was treated with GBHC
for 2 consecutive overnight along with all of their family members. For Groups 2 participants,
5% permethrin was used for treatment, again along with all of their family members. Group 3
received one dose of oral ivermectin 200mg/kg body weight and then another dose after two
weeks later. White soft paraffin was used to treat Group 4. Group 3 showed the best result—after
4 weeks, the group saw 96% clinical improvement and 100% reduced itching. The second best
result came from Group 2 which received permethrin 5%. The treatment led to 90% itching
reduction and clinical improvement. However, children less than 2 months old and pregnant or
nursing women cannot take the oral ivermectin and should take 6-10% precipitated sulfur for the
best result. For these people, ivermectin can cause mild burning, stinging, and recurrence of
pruritus.
Points 3, 4, 5 are from my personal interaction with Dr, Shwayder, dermatologist at Henry Ford
Hospital.
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- Source: Sullivan, John R., Geoffrey Watt, and Brent Barker. "Successful Use of Ivermectin in
the Treatment of Endemic Scabies in a Nursing Home." Australasian Journal of Dermatology
38.3 (1997): 137-40. Print.
In this study, ivermectin was used to treat endemic scabies found in a 33-bed rural
nursing home. According to the study, only oral ivermectin treatment was successful when other
treatment options, such as permethrin, gamma-benzene hexachloride, benzyl benzoate, etc. were
used but failed to produce any improvement. 6 weeks after the ivermectin treatment, all scabies
and rashes were eradicated at the home.
<Successful Intervention in Aboriginal Communities>
-source: Carapetis JR, Connors C, Yarmirr D, Krause V, Currie BJ. Success of a scabies control
program in an Australian Aboriginal community. Pediatr. Infect. Dis. J. 1997; 16: 494 9.
Dowden M. Scabies eradication day: Galiwinku community. Chronicle 1999; 2: 12
-source: Clin Microbiol Rev. 2007 Apr;20(2):268-79.
Problems in diagnosing scabies, a global disease in human and animal populations.
Walton SF, Currie BJ.
Med J Aust. 2001 Oct 1;175(7):367-70)
About 201 to 242 children aged 5 years and under were screened initially and at the three
follow-up screenings. The prevalences of scabies, infected scabies and non-scabies pyoderma
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before intervention were 35%, 12% and 11%, respectively. At 6 weeks after the intervention,
these numbers went down to 3%, 1% and 4%, respectively.
<Other Examples>
Taplin, P. "Community Control of Scabies: A Model Based on Use of Permethrin Cream." The
Lancet 337.8748 (1991): 1016-018. Print.
<Prevention>
- Source: Currie, Bart. "Skin Infections and Infestations in Aboriginal Communities in Northern
Australia." Wiley Online Library. Web. 02 Mar. 2012.
<http://onlinelibrary.wiley.com/doi/10.1046/j.1440-0960.2000.00417.x/full>.
-Source: Munoz E, Powers J, Nienhuys T, Mathews J. Social and environmental factors in 10
Aboriginal communities in the Northern Territory: Relationship to hospital admissions of
children. Med. J. Aust. 1992; 156: 529 33.
Gracey M, Williams P, Houston S. Environmental health conditions in remote and rural
Aboriginal communities in Western Australia. Aust. N.Z. J. Public Health 1997; 21: 511 18.
<Recent Outbreaks>
1. "Asheville School Reports Scabies Outbreak." Burlington Times News. Web.
<http://www.thetimesnews.com/articles/asheville-49107-school-outbreak.html>.
2. "Saint John Hit by Scabies Outbreak." Yahoo! News Canada. Web.
<http://ca.news.yahoo.com/saint-john-hit-scabies-outbreak-113053942.html>.
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- 4 students at Harbour View High School, 2 at St. Malachy’s Memorial High School, 1
at Simonds High School
<The Challenge Remains>
-Source: Walton, SF. "Scabies: New Future for a Neglected Disease." Adv Parasitol. 57 (2004):
309-76. Print.