Scabies (Sarcoptes scabiei)- Common in children, crowded populations (jails, nursing homes)- Mites that burrow into the stratum corneum and cause pruritus (worse at night)- Serpiginous burrows (lines) in webspace of hands and feet- Transmission through skin-to-skin contact or via fomites- Treatment: permethrin cream, washing/drying all clothing/bedding, treat close contacts.

Lice (Pediculus humanus/Phthirus pubis)- Blood-sucking insects- Cause intense pruritus with associated excoriations- Commonly on scalp and neck (head lice) or waistband and axilla (body lice)- Can transmit Rickettsia prowazekii (epidemic typhus), Borrelia recurrentis (relapsing fever), Bartonella quintana (trench fever)- Treatment: pyrethroids, malathion, ivermectin lotion, nit combind.