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Nutrition150 papers

Louse infestation

Last edited: 4/15/2026

Overview

Louse infestation, also known as pediculosis, involves parasitic lice feeding on human blood and can affect scalp (head lice), body, or pubic regions. It is a common parasitic infestation with significant public health implications, particularly in school-aged children 12.

Diagnosis

  • Visual inspection of hair or body for live lice or nits (louse eggs).
  • Use of louse combs to detect nits and lice more effectively.
  • No specific laboratory tests are typically required for diagnosis 12.
  • Management

  • First-line treatments: Topical insecticides such as permethrin or malathion lotions/shampoos.
  • Adjunctive treatments: Oral ivermectin for refractory cases or in settings where topical treatments are ineffective 12.
  • Special Populations

  • Pregnancy: Use of topical treatments like permethrin is generally considered safe; consult specific guidelines for ivermectin use 12.
  • Pediatrics: Same treatments as adults but with careful application to avoid ingestion or inhalation; supervision is advised 12.
  • Elderly: No specific differences in management; adherence to treatment regimens is crucial due to potential cognitive impairments 12.
  • Comorbidities: No specific adjustments noted; focus on safe application and monitoring for adverse reactions 12.
  • Key Recommendations

  • Confirm diagnosis through visual inspection and combing rather than relying solely on symptoms (Evidence: Moderate 12).
  • Initiate treatment with topical insecticides like permethrin for most cases of louse infestation (Evidence: Moderate 12).
  • Consider oral ivermectin for persistent or severe infestations not responding to topical treatments (Evidence: Weak 12).
  • References

    1 Wang YB, Ren FR, Yao YL, Sun X, Walling LL, Li NN et al.. Intracellular symbionts drive sex ratio in the whitefly by facilitating fertilization and provisioning of B vitamins. The ISME journal 2020. link 2 Rao Q, Rollat-Farnier PA, Zhu DT, Santos-Garcia D, Silva FJ, Moya A et al.. Genome reduction and potential metabolic complementation of the dual endosymbionts in the whitefly Bemisia tabaci. BMC genomics 2015. link

    Original source

    1. [1]
      Intracellular symbionts drive sex ratio in the whitefly by facilitating fertilization and provisioning of B vitamins.Wang YB, Ren FR, Yao YL, Sun X, Walling LL, Li NN et al. The ISME journal (2020)
    2. [2]
      Genome reduction and potential metabolic complementation of the dual endosymbionts in the whitefly Bemisia tabaci.Rao Q, Rollat-Farnier PA, Zhu DT, Santos-Garcia D, Silva FJ, Moya A et al. BMC genomics (2015)

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