Pubic lice are most often spread by sexual contact with an infested person. Body lice can be found on clothing and they are not known to burrow into the skin. Diagnosis
The condition is diagnosed by finding live lice and unhatched eggs in the hair. Finding empty eggs is not enough. Dandruff, lint, sand,  hair casts, and dried hairspray, can be mistaken for eggs and nits. This is made easier by using a magnifying glass or running a comb through the childs wet hair, the latter of which is the most assured method of diagnosis and can be used to monitor treatment. In questionable cases, a child can be referred to a health professional. However, head lice infestation is commonly overdiagnosed, with extinct infestations being mistaken for active ones. Infestations are only considered extinct if nits are more than 0.25 inches away from the scalp and nymphs and adult lice are absent. As a result, lice-killing treatments are more often used on non-infested than infested children. The use of a louse comb is the most effective way to detect living lice. With both methods, special attention should be paid to the area near the ears and the nape of the neck. The use of a magnifying glass to examine the material collected between the teeth of the comb could prevent misdiagnosis.The presence of nits alone, however, is not an accurate indicator of an active head louse infestation. Generally, white nits are empty egg casings, while brown nits may still contain viable louse larva.
Dimethicone is between 70 and 97% effective with a low rate of side effects, and thus is seen as the preferred treatment. It works by physical means and there is no evidence of pesticide resistance. Ivermectin is around 80% effective, but can cause local skin irritation. Malathion has an effectiveness around 90%, but theres the possibility of toxicity. Pyrethroids such as permethrin, while commonly used, have lower rates of effectiveness due to the resistance among lice. Effectiveness varies from 10 to 80%, depending on the population studied. Medications within a lotion appear to work better than those within a shampoo. Benzyl alcohol appears effective but it is unclear if it is better than standard treatments. Abametapir was approved for medical use in the United States in July 2020.Resistance to several commonly used treatments is increasing worldwide, with patterns of resistance varying by region. Head lice have demonstrated resistance to permethrin, malathion, phenothrin, and carbaryl in several countries around the world. A previous method used to delay resistance included utilizing a rotating list of recommended insecticides by health authorities. The mosaic model is the current recommendation, in which it is advised to use one product for a treatment course, followed by a different insecticide from another substance class if the first treatment fails. Home Remedies
Tea tree oil has been promoted as a treatment for head lice; however, there is no clear evidence of its effectiveness.