Special Operations Forces Medical Handbook

4-62

secondary focus of pruritus. Often the pruritus persists despite normal hygienic routines if the patient has a
hypersensitivity to the mite or its products.

Follow-up Actions
Reevaluation: Repeat examination for those with continued nocturnal exacerbation of their pruritus. This
is the feeding time of the scabies mite and will help differentiate between a hypersensitivity reaction and
persistent infestation. Consult dermatology.
Evacuation/Consultation Criteria: No need to evacuate. Consult dermatology as needed.

Zoonotic Disease Considerations
Principal Animal Hosts: Cattle, dogs, and cats
Clinical Disease in Animals: Intense pruritus, lesions start on head, neck and shoulders and can spread
to the rest of the body.
Probable Mode of Transmission: Contact with infected animals.

Skin: Pediculosis (Lice)

(crab lice, head lice, body lice)

MAJ Daniel Schissel, MC, USA

Introduction: A parasitic infestation of the skin—scalp, trunk, or pubic areas—that usually occurs in
overcrowded dwellings. Head and pubic lice are found on the head and in the pubic area. Body lice are
seldom found on the body (only getting on the skin to feed), but can be found in the seams of clothing.

Subjective: Symptoms
Pediculus humanus capitus (head louse): pruritus of the sides and back of the scalp. Pediculus humanus
corporis (body louse): localized or generalized pruritus on the torso. Pthirus pubis (crab louse): asymptomatic
or mild to moderate pruritus in the pubic area for months.

Objective: Signs
Using Basic Tools: Head Lice: <10 organisms usually identied with naked eye or hand lens. The nit
(1 mm oval, gray, rm capsule) cemented to the hair is the egg remnant of a hatched louse. New, viable
eggs have a creamy yellow color. The infestation can be dated from the location of the nit, since they are
deposited at the base of the hair follicle and the hair grows 0.5 mm daily. Also: excoriation, secondary
infection and adenopathy.
Body Lice: Excoriated, small erythematous papules localized to the torso area. Nits and lice are found in
the in the seams of clothes.
Crab Lice: 1-2 mm brown to gray specks in the hair-bearing areas of the genital region. Nits appear as tiny
white adhesions to the hair. Small erythematous papules at the sites of feeding, especially in the periumbilical
area. Secondary excoriation and lichenication may be present. Maculae caeruleae are non-blanchable blue
to gray macules, 5-10 mm in diameter, at the site of a bite that result from the breakdown of heme by the
louse saliva. These lesions may be found from the groin to the eyelash. Adenopathy may be observed with
secondary infections.

Assessment: Diagnose based on clinical ndings and conrm with identication of lice or nits.
Differential Diagnosis - irritant or allergic dermatitis, arthropod reaction, seborrheic dermatitis, scabies,
eczematous dermatitis, folliculitis. Differentiate by nding lice or nit.

Plan:
Treatment
Primary:

1. Wash bedding in hot water. Clothing items that cannot be washed should be sealed in an airtight bag
   for 2 weeks or dry-cleaned.


2. Apply permethrin 1% rinse to the scalp and wash off after 10 min.