How quickly do lice multiply after infection? - briefly
Lice eggs hatch in roughly 7–10 days, and the nymphs reach reproductive maturity in an additional 6–10 days, enabling the population to double about every 5–6 days under favorable conditions. Consequently, a modest infestation can grow to dozens of insects within two to three weeks.
How quickly do lice multiply after infection? - in detail
Lice begin reproducing within a few days after a host becomes infested. Adult females lay 6–10 eggs (nits) per day, attaching them near the scalp base. Eggs hatch in 7–10 days under optimal temperature (30 °C) and humidity (70 %). Emerging nymphs undergo three molts, each lasting about 2–3 days, reaching sexual maturity roughly 2 weeks after hatching. Consequently, a single adult female can produce 30–40 viable offspring during her 30‑day lifespan, allowing the population to double every 5–7 days in favorable conditions.
Key factors influencing the multiplication speed:
- Temperature: Higher ambient heat accelerates egg development and nymph growth.
- Humidity: Moist environments sustain egg viability; low humidity prolongs incubation.
- Host grooming: Frequent combing or washing removes nits, reducing reproductive output.
- Crowding: Dense infestations increase mating opportunities, enhancing population expansion.
The combined effect of rapid egg laying, short incubation, and swift nymph maturation results in a noticeable rise in lice numbers within two weeks of initial infestation. Prompt treatment that eliminates both adults and eggs is essential to interrupt this cycle.