People usually do not have symptoms of having head lice for several weeks after becoming infested. A common symptom is itching which is also common with dandruff and dry skin.
People get head lice from other infested people mostly when they have head to head contact as head lice to not fly, swim, or jump.
It is easier to treat head lice when found "early" so checking hair for head lice at home is important for any symptoms or even periodically.
