Nits are firmly attached to the hair shaft close to the scalp behind the ears and on the back of the neck. Adult lice are spread mainly by direct contact with infested persons or by using infested articles such as hats, wigs, hairbrushes, combs, towels, scarves and hair rollers. Even using the same bed or sitting on upholstered furniture that an infested person used can spread lice. Head lice are usually not found below the neck of an individual but have been recorded in armpits and even the chest. Usually children under 12 years of age are more sensitive to lice feeding than any other age group.
Head lice can survive off the host two to three days.
Crab lice are found primarily in the pubic region but can occur in the armpits, beards and eyebrows. These lice are spread during sexual intercourse and only rarely are spread by loose hairs left on bedding and toilets by infested persons. Crab lice die after 12 to 48 hours if not attached to a human. Control Measures Control of human lice is a medical problem that must be left to a physician, pharmacist or health department personnel. Treating the premises is seldom necessary since lice cannot live off the host for indefinite periods of time.