How are clothing lice transmitted? - briefly
Clothing lice spread through direct contact with infested garments, bedding, or towels that contain the insects or their eggs. Sharing or reusing unlaundered items allows the parasites to move to clean clothing, thereby facilitating transmission.
How are clothing lice transmitted? - in detail
Clothing lice (Pediculus humanus corporeus) spread primarily through contact with contaminated garments, linens, or personal items. When an infested person wears clothing, the lice lay eggs (nits) on seams and folds. Eggs hatch within 7–10 days, and newly emerged nymphs feed on the host’s blood while remaining attached to the same article of clothing. If the garment is transferred to another individual—by sharing coats, uniforms, blankets, or towels—the lice move to the new host, establishing a fresh infestation.
Transmission occurs in three main ways:
- Direct person‑to‑person transfer of infested clothing or accessories.
- Indirect transfer via fomites such as bedding, laundry baskets, or storage containers that have not been laundered.
- Environmental exposure in overcrowded settings where clothing is exchanged frequently and hygiene facilities are limited.
Key factors that increase risk include:
- Poor laundering practices (cold water, insufficient drying time).
- Crowded living conditions (shelters, refugee camps, prisons).
- Lack of access to clean clothing and personal hygiene supplies.
- Use of infrequently washed or shared garments, especially outerwear with multiple pockets.
The life cycle reinforces transmission. After hatching, nymphs mature in 5–7 days, during which they remain on the same garment. Adult lice survive up to 30 days without a blood meal, allowing them to persist on clothing left unattended for weeks. Eggs attached to fabric are resistant to desiccation and can remain viable for months, reactivating when the garment is worn again.
Control measures target each transmission route:
- Wash all potentially contaminated textiles at ≥ 60 °C, followed by a hot‑dry cycle.
- Iron clothing and bedding to destroy nymphs and eggs.
- Isolate infested garments from clean items during treatment.
- Provide disposable or regularly laundered clothing in high‑risk environments.
- Apply insecticidal powders or sprays to clothing when washing facilities are unavailable.
Understanding these mechanisms enables effective interruption of the spread, reducing the prevalence of clothing‑borne lice infestations.