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Section 3. Summaries of Infectious Diseases
Pediculosis Capitis
1
(Head Lice)
Clinical Manifestations
Etiology
Epidemiology
Diagnostic Tests
Treatment
Isolation of the Hospitalized Patient
Control Measures
CLINICAL MANIFESTATIONS: Itching is the most common symptom
of head lice infestation, but many children are asymptomatic.
Adult lice or eggs (nits) are found in the hair, usually behind
the ears and near the nape of the neck. Excoriations and crusting
caused by secondary bacterial infection may occur and often
are associated with regional lymphadenopathy. In temperate climates,
head lice deposit their eggs on a hair shaft 3 to 4 mm from
the scalp. Because hair grows at a rate of approximately 1 cm
per month, the duration of infestation can be estimated by the
distance of the nit from the scalp.
ETIOLOGY: Pediculus humanus capitis is the head louse. Both
nymphs and adult lice feed on human blood.
EPIDEMIOLOGY: Head lice infestation in children attending child
care and school is common in the United States. Head lice are
not a sign of poor hygiene, and all socioeconomic groups are
affected. Infestations are less common in African-American children
than in children of other races in the United States. Head lice
infestation is not influenced by hair length or frequency of
shampooing or brushing. Head lice are not a health hazard, because
they are not responsible for spread of any disease. Transmission
occurs by direct contact with hair of infested people and uncommonly,
by contact with personal belongings, such as combs, hair brushes,
and hats. Head lice may survive up to 2 days away from the scalp,
and their eggs cannot hatch at a lower ambient temperature than
that close to the scalp.
The incubation period from the laying of eggs to the hatching of the first nymph is 10 to 14 days but may be . . . [Go to Full Text]
Related text in Red Book:
- Pediculosis Pubis (Pubic Lice)
Red Book
2006: 492-493.
[Extract]
[Full Version]
- Drugs for Parasitic Infections
Red Book
2006: 790-820.
[Extract]
[Full Version]
This topic has been referenced by these articles:
- Pearlman, D. L.
(2005). Nuvo Lotion and the Future of Head-Lice Treatment. Pediatrics
115: 1452-1453
[Full Version]
- Williams, L. K., Reichert, A., MacKenzie, W. R., Hightower, A. W., Blake, P. A.
(2001). Lice, Nits, and School Policy. Pediatrics
107: 1011-1015
[Abstract]
[Full Version]
- Hipolito, R. B., Mallorca, F. G., Zuniga-Macaraig, Z. O., Apolinario, P. C., Wheeler-Sherman, J.
(2001). Head Lice Infestation: Single Drug Versus Combination Therapy With One Percent Permethrin and Trimethoprim/Sulfamethoxazole. Pediatrics
107: 30e-30
[Abstract]
[Full Version]
- Pollack, R. J.
(2001). Head Lice Infestation: Single Drug Versus Combination Therapy. Pediatrics
108: 1393-1393
[Full Version]
- Frankowski, B. L., Weiner, L. B., Committee on School Health, , Committee on Infectious Diseases,
(2002). Head Lice. Pediatrics
110: 638-643
[Abstract]
[Full Version]
-
(2002). ERRATUM. Pediatrics
110: 1300-1300
[Full Version]
- Pearlman, D.
(2005). Cetaphil Cleanser (Nuvo Lotion) Cures Head Lice. Pediatrics
116: 1612-1612
[Full Version]
- Pearlman, D. L.
(2004). A Simple Treatment for Head Lice: Dry-On, Suffocation-Based Pediculicide. Pediatrics
114: e275-e279
[Abstract]
[Full Version]