As children have returned to in-person learning and sports, cases of head lice become even more common. Head lice are tiny parasitic insects that feed on human blood and cling to the scalp and neck. Each louse is only about the size of a sesame seed and is tan, grey, or brown. Lice lay light, pale eggs (nits) on hairs near the scalp that are held together with a glue-like substance. Although lice cannot fly,