title: Head Lice.
abstract: BACKGROUND
  Conflicting information about the proper treatment of head lice has given rise to uncertainty among patients and treating personnel. For example, the reported efficacy of permethrin fell from 97% in the 1990s to 30% in 2010.
  
  
  METHODS
  Review of the literature based on a selective search of PubMed.
  
  
  RESULTS
  In Germany, outbreaks of head lice mainly occur among 5- to 13-year-olds returning to school after the summer vacation. Nymphs hatch from eggs after an average of 8 days and become sexually mature lice over the ensuing 9 days. The main route of transmission is direct head-to-head contact; transmission via inanimate objects is of no relevance. Symptoms arise 4-6 weeks after an initial infestation; many affected persons have no symptoms at all. Wet combing is the most sensitive method of establishing the diagnosis and monitoring treatment. Resistance to neurotoxic pediculocidal drugs is increasing around the world. Dimethicones are the treatment of choice, with 97% efficacy. Outbreaks must be managed with the synchronous treatment of all infested persons to break the chain of infestation. If the agent used is not ovicidal, the treatment must be repeated in 8-10 days and sometimes in a further 7 days as well.
  
  
  CONCLUSIONS
  Outbreaks of head lice can be successfully terminated by synchronous treatment with ovicidal dimethicones.
authors.affiliation: Department of Dermatology, Venereology and Allergology, University Hospital Frankfurt/Main.
authors.forename: Laura
authors.initials: L
authors.lastname: Meister
authors.forename: Falk
authors.initials: F
authors.lastname: Ochsendorf
mesh_terms: D000818:Animals; D004196:Disease Outbreaks; D005858:Germany; D006801:Humans; D007306:Insecticides / Q000627:therapeutic use; D010373:Lice Infestations / Q000188:drug therapy* / Q000453:epidemiology; D010374:Pediculus; D026023:Permethrin / Q000627:therapeutic use*
chemical_list: D007306:Insecticides; D026023:Permethrin