Head lice are an obligate ectoparasite of humans. These wingless insects live their entire lives on the human scalp and feed on the blood of their host. Humans are the only known host for this species, though close relatives can also be found in chimpanzees. They are difficult to detect and treat.
Checking the hair for live lice is a good first step in diagnosing an infestation. Head lice are small, and their eggs are usually laid close to the scalp. The eggs are usually whitish or white, and they are attached to hair shafts with a glue-like substance. If you find any eggs or nits, you will need a fine-tooth comb to remove them.
If you suspect your child has head lice, go to the doctor. He or she can give you stronger medicine or prescribe you a treatment. It is also important to remember that swimming can reduce the effectiveness of many head lice medicines. If your child is swimming in public pools, you might need to consult with a health care provider to ensure that your child is actually free of lice.
When looking for lice, it is important to remember that they live in the hair, so they are attracted to warm areas of the scalp. Consequently, they will often bite your scalp, leaving behind small red bumps that may be crusted with blood. Scratching too hard may result in infection, so it is crucial to be gentle while searching.