Human Head Lice

Named for their propensity to inhabit the heads of humans, head lice are not indicative of uncleanliness or poverty; head lice can affect anyone. Although they are not transmitters of disease, they can cause extreme irritation and may prevent blood from clotting.

A human head lice infestation causes itching on the scalp and a black residue to appear on the back of the neck. This black powder is the excretion of the head lice.  Lice can be removed manually with nit combs and home remedies, including mayonnaise and baby oil, but their effectiveness has not been confirmed.

The entire life cycle of head lice takes place on the human body, and human head lice cannot survive more than two days away from their host. However, head lice move easily from host to host and can spread through close contact, as when an infected person shares clothing or combs with another person. To prevent an infestation from spreading to another host, all bedding and clothing should be washed thoroughly at high temperatures.