Are scabies and public lice the same thing?
No, though they have several things in common. Both are parasites that infect the skin and are spread through close physical contact, though not exclusively sexual contact. An example would be the sharing of bed clothes or towels. Both parasites cause itching, and both are treated with topical drugs that essentially poison them.
Scabies is an infection caused by the itch mite, a sort of microscopic tick that burrows into the skin and lays eggs, which then hatch and develop into adults within 10 days. Symptoms include itchy burrows on the hands and wrists in a majority of cases. These burrows also can be found on the chest, buttocks, thighs and penis. Scabies is seldom found on the neck or face.
Lice, on the other hand, come in three species that infect humans–head, body and pubic lice. All three are visible to the naked eye and lay eggs (nits) that are visible, usually at the base of hair follicles. As you might guess, pubic lice (also called crabs) are the species most likely to be sexually transmitted.
How is scabies diagnosed and treated?
For diagnosis, a health care provider will take a sample of the burrows and examine it under a microscope for the characteristic wavy shape of the burrow. Treatment consists of applying a topical ointment or cream over the entire body from the neck down. The treatment is washed off after 8 to 12 hours. Antihistamines may be used to quell the itching that sometimes continues after treatment. Frequently, the infected person’s family members, who are at high risk for exposure, are also treated, even if they have no symptoms.
How are lice diagnosed and treated?
Pubic lice usually are identified based on a medical history and physical examination for either the lice or nits. They can be treated with a variety of topical drugs and shampoo preparations that are applied to the skin and then washed off after a specified number of hours. It’s important to remove the medication, because it can cause a rash or skin problems. Some of the medications used for scabies are also used for lice, including permethrin (Elimite®, Nix ®) and lindane (Kildane®, Scabene®). Be careful to follow your health care provider’s instructions about which type of formulation to use and how to apply it.
What about infestation in the household? How do you get rid of the lice and scabies that may not be killed by medication?
The house does not have to be fumigated, but bedding and clothing should be decontaminated. Wash them in hot water or send them to be dry cleaned. Lice and crabs will generally die if deprived of a human host for three days.