What else can infest hair besides lice? - briefly
Hair can harbor Demodex mites, fungal spores causing tinea capitis, bacterial colonies that produce folliculitis, and occasional arthropods such as fleas, ticks, or bedbugs. These organisms may cause itching, scaling, or visible debris similar to lice.
What else can infest hair besides lice? - in detail
Hair can host a variety of organisms besides the common head louse. These include arthropods, microscopic mites, fungal pathogens, bacterial agents, and larval insects that may temporarily occupy the scalp or body hair.
Arthropod parasites
- Head and body mites such as Demodex folliculorum and Demodex brevis live in hair follicles and sebaceous glands. Overpopulation causes itching, erythema, and a gritty texture. Diagnosis relies on microscopic examination of plucked hairs or skin scrapings. Topical acaricides (e.g., tea‑tree oil, ivermectin cream) reduce mite numbers.
- Sarcoptes scabiei (scabies) can colonize the scalp, especially in infants. Burrows appear as fine, linear tracks amidst intense pruritus. Permethrin 5 % cream applied overnight eradicates the mite.
- Fleas (Ctenocephalides spp.) occasionally embed in dense hair, producing localized irritation and secondary bacterial infection. Effective control uses insecticidal shampoos and environmental treatment.
Larval infestations (myiasis)
- Dermatobia hominis (human botfly) deposits eggs on hair shafts; larvae develop under the skin, forming a painful, inflamed nodule. Surgical extraction or occlusive methods (e.g., petroleum jelly) force the larva to emerge.
- Cutaneous myiasis caused by blowfly larvae may involve hair as a site of oviposition, leading to rapid tissue breakdown. Prompt debridement and systemic antibiotics prevent complications.
Fungal pathogens
- Tinea capitis (ringworm of the scalp) presents with patchy alopecia, scaling, and sometimes black dots where hairs break at the surface. Diagnosis uses Wood’s lamp fluorescence or culture. Oral terbinafine or griseofulvin for 6–8 weeks clears the infection; adjunctive antifungal shampoos reduce transmission.
- Malassezia spp. (dandruff, seborrheic dermatitis) proliferate on scalp hair, causing flaking and mild itching. Ketoconazole or selenium sulfide shampoos suppress overgrowth.
Bacterial conditions
- Folliculitis involves colonization of hair follicles by Staphylococcus aureus or Pseudomonas aeruginosa. Symptoms include pustules, tenderness, and occasional crusting. Topical mupirocin or systemic antibiotics treat the infection; hygiene measures prevent recurrence.
- Impetigo may spread to hair‑covered areas, producing honey‑colored crusts. Mupirocin ointment applied three times daily resolves lesions within a week.
Other non‑parasitic agents
- Pediculosis corporis (body lice) can cling to coarse body hair, especially in crowded conditions. Removal involves thorough washing of clothing and skin with insecticidal soaps.
- Dust mites reside in bedding and hair may pick up allergenic particles, provoking contact dermatitis. Regular laundering at ≥ 60 °C diminishes allergen load.
Effective management requires accurate identification, appropriate pharmacologic therapy, and environmental control to prevent reinfestation. Regular scalp examination, especially in children, travelers, and immunocompromised patients, facilitates early detection of these diverse hair‑dwelling organisms.