| Head lice infestation | |
|---|---|
| Other names | Pediculosis capitis,[1] nits,[2] cooties[3] |
 | |
| Head lice bites on the back of the neck | |
| Specialty | Pediatrics, infectious disease |
| Symptoms | Itching that can result in trouble sleeping[4][5] |
| Usual onset | Up to six weeks from infestation[5] |
| Causes | Head louse spread by direct contact[4][6] |
| Diagnostic method | Finding live lice[5] |
| Treatment | Combing the hair with a fine tooth comb, shaving the head, medications[7] |
| Medication | Malathion, ivermectin, dimethicone[7] |
| Prognosis | Not serious[7] |
| Frequency | Common[5] |
Head lice infestation, also known as pediculosis capitis and nits, is the infection of the head hair and scalp by the head louse (Pediculus humanus capitis).[1] Itching from lice bites is common.[5] During a person's first infection, the itch may not develop for up to six weeks.[5] If a person is infected again, symptoms may begin much more quickly.[5] The itch may cause problems with sleeping.[4] Generally, however, it is not a serious condition.[7] While head lice appear to spread some other diseases in Africa, they do not appear to do so in Europe or North America.[4][6]
Head lice are spread by direct contact with the hair of someone who is infected.[4] The cause of head lice infestations are not related to cleanliness.[5] Other animals, such as cats and dogs, do not play a role in transmission.[4] Head lice feed only on human blood and are only able to survive on human head hair.[6][5] When adults, they are about 2 to 3 mm long.[8] When not attached to a human, they are unable to live beyond three days.[5] Humans can also become infected with two other lice – the body louse and the crab louse. To make the diagnosis, live lice must be found.[5] Using a comb can help with detection.[5] Empty eggshells (known as nits) are not sufficient for the diagnosis.[5]
Possible treatments include: combing the hair frequently with a fine tooth comb or shaving the head completely.[7] A number of topical medications are also effective, including malathion, ivermectin, and dimethicone.[7] Dimethicone, which is a silicone oil, is often preferred due to the low risk of side effects.[7] Pyrethroids such as permethrin have been commonly used; however, they have become less effective due to increasing pesticide resistance.[7] There is little evidence for alternative medicines.[9]
Head-lice infestations are common, especially in children.[5] In Europe, they infect between 1 and 20% of different groups of people.[6] In the United States, between 6 and 12 million children are infected a year.[4] They occur more often in girls than boys.[5] It has been suggested that historically, head lice infection were beneficial, as they protected against the more dangerous body louse.[10] Infestations may cause stigmatization of the infected individual.[5]
References
edit- ^ a b Bolognia, Jean L.; Schaffer, Julie V.; Duncan, Karynne O.; Ko, Christine (2022). "71. Infestations: head lice". Dermatology Essentials (2nd ed.). Elsevier. pp. 735–737. ISBN 978-0-323-70971-2. Archived from the original on 12 February 2024. Retrieved 12 February 2024.
- ^ "How to treat nits". nhs.uk. 2012-09-14. Archived from the original on 17 October 2014. Retrieved 23 October 2014.
- ^ "cootie". dictionary.reference.com. Archived from the original on 7 November 2014. Retrieved 23 October 2014.
- ^ a b c d e f g "Parasites - Lice - Head Lice Frequently Asked Questions (FAQs)". cdc.gov. 24 September 2013. Archived from the original on 15 October 2014. Retrieved 23 October 2014.
- ^ a b c d e f g h i j k l m n o p Smith CH, Goldman RD (August 2012). "An incurable itch: head lice". Canadian Family Physician. 58 (8): 839–41. PMC 3418981. PMID 22893334.
- ^ a b c d Feldmeier H (September 2012). "Pediculosis capitis: new insights into epidemiology, diagnosis and treatment". European Journal of Clinical Microbiology & Infectious Diseases. 31 (9): 2105–10. doi:10.1007/s10096-012-1575-0. PMID 22382818.
- ^ a b c d e f g h "Head lice. Dimeticone is the pediculicide of choice". Prescrire International. 23 (151): 187–90. July 2014. PMID 25162097.
- ^ "Parasites - Lice - Head Lice". cdc.gov. 24 September 2013. Archived from the original on 23 November 2014. Retrieved 23 October 2014.
- ^ Takano-Lee M, Edman JD, Mullens BA, Clark JM (December 2004). "Home remedies to control head lice: assessment of home remedies to control the human head louse, Pediculus humanus capitis (Anoplura: Pediculidae)". Journal of Pediatric Nursing. 19 (6): 393–8. doi:10.1016/j.pedn.2004.11.002. PMID 15637580.
- ^ Rózsa L, Apari P (May 2012). "Why infest the loved ones--inherent human behaviour indicates former mutualism with head lice". Parasitology. 139 (6): 696–700. doi:10.1017/S0031182012000017. PMID 22309598.