Visual Exam for Lice

Exam Overview

During a visual exam for head lice, the hair on the head is parted with the fingers so that the scalp can be seen. You or the doctor uses a louse comb and looks for tiny live lice[about 3 mm (0.12 in.) to 4 mm (0.16 in.) long, or the size of a sesame seed]. If you are checking your child or someone else for lice, it may be helpful to use a handheld magnifying glass or have another person help you. The doctor may use a special light called a Woods lamp in a darkened room to see the lice better.

• Lice move quickly to avoid light, so they may be difficult to see.
• Eggs (nits) are small and white or light brown. They are usually found on the hair shaft close to the scalp. They do not slide up and down the hair shaft.
• If eggs are found farther from the scalp, the person may have been infested with lice for some time. If the eggs have already hatched, the empty egg cases may appear white.

Pubic lice may look like yellowish brown or gray specks or small scabs. They are smaller than head lice [about 1 mm (0.04 in.) to 2 mm (0.08 in.) long] and are wider than they are long.

Body lice and their eggs may be seen in the seams of clothing. They are usually not found on the body, although there may be small, red bumps on the skin where the lice have bitten. The lice look like large head lice and may be up to 4 mm (0.16 in.) long.