How long do scabies mites live? - briefly
Adult scabies mites survive approximately 30–45 days, after which they die. Females lay eggs throughout this period, sustaining the infestation.
How long do scabies mites live? - in detail
Scabies mites survive on a human host for roughly one month. An adult female lives about 30–40 days, during which she deposits 10–15 eggs each day. Eggs hatch within 3–4 days, releasing larvae that migrate to the skin surface. After another 4–5 days, larvae molt into nymphs, which mature into reproductive adults in roughly a week. Consequently, the complete life cycle—from egg to egg‑laying adult—takes about 10–14 days.
Outside a host, the organisms endure only briefly. In dry, cool environments they die within 24–48 hours; in warm, humid conditions they may persist up to 5–7 days. Survival beyond a week is rare, even with optimal temperature (25–30 °C) and humidity (>70 %). Consequently, indirect transmission via bedding or clothing is limited to a few days after removal from an infested person.
Key factors influencing longevity:
- Temperature: 25–30 °C extends survival; below 15 °C accelerates mortality.
- Humidity: High relative humidity (>70 %) slows desiccation; low humidity (<40 %) shortens life.
- Host availability: Continuous access to skin supplies nutrients and protection, allowing the full month‑long lifespan.
Treatment efficacy aligns with the mite’s life span. Topical scabicides eradicate existing adults and nymphs within 24 hours, but eggs remain resistant. A second application after 7–10 days targets newly hatched larvae, ensuring complete eradication before the next generation can reproduce. Oral ivermectin follows a similar schedule, with doses spaced 7 days apart to cover the entire developmental period.
In summary, the organism remains viable on a person for about 30–40 days, completes a life cycle in 10–14 days, and survives off‑host for no more than a week under favorable conditions. Treatment protocols exploit these timelines to interrupt reproduction and achieve cure.