Fast Five Quiz: Are You Ready to Face Back-to-School Health Concerns?

Germaine L. Defendi, MD, MS


August 19, 2014

Head lice infestation, caused by Pediculus humanus capitis or the head louse, is most common in urban areas. Major infestations affect children of all socioeconomic groups and do not reflect poor hygiene habits. These infestations do not spread disease. Head lice infestations occur most often in children attending child-care and in those attending school, typically during the late summer and fall.

In North America, the reported incidence of head lice infestation is lower among African American persons than any other racial group. This is probably due to the use of pomades (waxy hair-styling products) and because the head louse claw is more adapted to attach to the round and oval-shaped hair shafts found in white and Asian persons than the flattened elliptical hair shaft of African American persons.

Transmission primarily occurs through direct head-to-head contact with the hair of infested persons. Girls are at higher risk for head lice infestation than boys because of social behavior (eg, social acceptance of close physical contact and sharing of hats, combs, or hair ties); hair length is not a factor.

Recently, resistant head lice have become a concern. Newer topical treatments have been developed, including 0.5% ivermectin lotion. These topical preparations are not recommended as first-line treatments but may be useful in combating resistant lice.

For more information on the epidemiology of pediculosis, read here.


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