How long after treatment with cold fog do bedbugs die? - briefly
Bedbugs usually succumb within 24–48 hours after a cold‑fog application, provided the fog reaches all infestation sites. Mortality may extend to several days if the fog’s concentration is low or the insects are shielded in deep crevices.
How long after treatment with cold fog do bedbugs die? - in detail
Cold‑fog (cryogenic fog) works by rapidly lowering ambient temperature to a level that is lethal for Cimex lectularius. Contact with the fog causes immediate chilling of the insect’s exoskeleton, leading to ice crystal formation inside cells and rapid loss of physiological function.
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Immediate effects: Within seconds of exposure, adult and nymphal bed bugs become immobilised. Neuromuscular activity ceases, but visible death may not be apparent until the insects rewarm.
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Time to observable mortality: Most individuals show irreversible damage within 5–10 minutes after the fog dissipates. Laboratory tests report 90 % mortality at 7 minutes post‑exposure when the fog temperature reaches –30 °C.
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Factors influencing duration:
- Temperature reached: Lower fog temperatures increase speed of lethal action. A fog that only reaches –15 °C may require up to 20 minutes for comparable mortality.
- Exposure time: Longer fog exposure (30 seconds to 2 minutes) enhances penetration into hiding places, reducing the time needed for complete kill.
- Life stage: Eggs are more tolerant; they often survive initial chill but fail to hatch if the fog remains below –20 °C for at least 15 minutes.
- Resistance level: Populations with documented heat‑resistance do not show increased tolerance to cold, so the timeline remains consistent across strains.
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Post‑treatment monitoring: After the fog clears, inspect treated areas after 24 hours. Survivors, if any, are usually weak and die within the next 48 hours. Repeat application is recommended if live insects are observed after this period.
In practice, a single cold‑fog application eliminates the majority of the adult and nymph population within 10 minutes, while eggs require a secondary exposure or a follow‑up treatment within 24–48 hours to ensure full eradication.