Aerosols or mists, especially ultra low volume spray techniques, are used for outdoor control of adult mosquitoes in addition to treatment of breeding sources. Aerosols are considered desirable in preventing annoyance by mosquitoes in limited bivouac areas. Aerosol operations should be accomplished when wind speeds are less than 6 knots and when target species are active. Residual sprays have limited applicability for the protection of small camps. When used, the spray is applied to all vegetation surfaces for an area of 30 meters (32.8 yds) or more around the place to be protected. Additional protective measures include screening living quarters, personal protection with insect repellents, insect repellent jackets, bed nets, and locating camps away from standing water and native villages to avoid contact with potentially infected mosquitoes.
LICE. The infestation of the hairy parts of the body with lice is called pediculosis. Human lice are responsible for the transmission of louseborne typhus, trench fever, and louse-borne relapsing fever. Louse-borne typhus is one of the few insecttransmitted diseases for which man serves as the reservoir. Trench fever is thought to be related to typhus fever. It does not kill, but it can be a debilitating epidemic disease among louse-infested troops. Louse-borne relapsing fever is caused by a spirochete. It is most prevalent in parts of Europe, North Africa, and Asia. In addition to serving as a vector of these serious diseases, lice cause a great deal of misery for infested people. Human louse species do not normally infest animals.
Three types of lice infest man: the body louse, Pediculosis humanus corporis; the head louse P. humanus capitis; and the crab louse, Phthirus pubis. The body louse is found on the body and along the seams of undergarments. The head louse is found on the head and neck, clinging to hairs. The eggs (nits) of the head louse are firmly attached to the hair. Head and body lice are normally acquired by personal contact, by wearing infested clothing, or by using contaminated objects such as combs and brushes.
Crab lice usually infest the pubic and anal regions, but occasionally also the eyebrows, armpits, and other areas of the body. These insects feed intermittently for many hours at a time and are unable to survive more than a short time away from the host. Crab lice are spread mainly by physical contact during sexual intercourse.
Control of lice includes delousing of individuals, treatment of infested clothing, bedding, living areas, and toilet facilities, and the prevention of new infestations. Louse control measures should be coordinated with a medical officer. The following preventive measures should be taken, especially during crowded shipboard and tenting conditions:
1. Treat louse-infested individuals and materials immediately.
2. Encourage personal cleanliness, i.e., at least weekly showers with soap and water and clothing changes (particularly underclothing).
3. Avoid overcrowding of personnel.
4. Instruct personnel on the detection and prevention of louse infestation.
Individual louse treatment measures include dusting with louse insecticide powder issued in a 2-ounce (56.7 g) shaker can.
For prevention or treatment of body louse infestations, wash all clothing and bedding in hot water and repeat in 7 to 10 days. If washing clothes is not practical because of travel or combat, application of an insecticidal dust is recommended. Dust the entire surface of the underwear and any other clothing worn next to the skin, including the shirt, as well as along the seams of outer garments. Rub the treated clothing lightly to spread the powder. About 30 g (1 .07 oz) of insecticide per person is required. If clothing cannot be conveniently removed, unbutton the shirt and trousers and dust the powder liberally on the inside of the underwear or other garments next to the skin. Then pat the clothes by hand to ensure distribution of the powder. Toilet facilities, along with extra clothing and bedding, should also be dusted.
Insecticidal shampoos issued by physician prescriptions are the method of choice for the treatment of head and crab lice.
BEDBUGS. Bedbugs are occasional pest aboard ship. They are not known vectors of human diseases, but they are annoying and can seriously affect morale. Bedbugs are approximately 1/5-inch long (5.1 mm), flat, reddishbrown insects with piercing and sucking mouth parts. They have nocturnal movement and feed only on blood. Their bite usually produces small, hard, white swellings (wheals). Habitual hiding places of bedbugs, such as the seams of mattresses, will often be obvious by the presence of dried black or brown excrement stains on surfaces where they congregate and rest. Their presence may also be indicated by blood stains on bedding.