How many days after cold fog treatment do bedbugs die? - briefly
Bed bugs exposed to a cold‑fog application usually die within 2–4 days, with the majority of mortality occurring by the third day. Mortality rates reach near‑complete levels after four days of continuous exposure.
How many days after cold fog treatment do bedbugs die? - in detail
Cold‑fog (cryogenic aerosol) treatments target bed‑bug populations by exposing insects to sub‑freezing temperatures combined with a carrier gas. Mortality does not occur instantly; the lethal process unfolds over several days.
The typical timeline is:
- Immediate effects (0‑24 hours). Exposure to temperatures below –20 °C can cause rapid chill‑injury in adult insects, resulting in observable paralysis and death within the first day for a portion of the population.
- Short‑term effects (24‑72 hours). Surviving adults and late‑stage nymphs experience physiological stress that leads to delayed mortality. Laboratory data show 70‑90 % mortality by the end of the third day.
- Extended effects (3‑7 days). Early‑stage nymphs, which are more tolerant to cold, often succumb during this period as metabolic functions deteriorate. Overall mortality rates approach 95‑100 % by the seventh day.
- Residual impact (7‑14 days). Any eggs or newly hatched nymphs that escaped initial exposure may be eliminated by secondary cold‑shock cycles that occur as the fog settles and dissipates. Complete eradication is typically confirmed after two weeks.
Factors influencing the exact duration include:
- Ambient temperature and humidity. Higher ambient temperatures reduce the cold‑fog’s penetration, extending the time needed for full mortality.
- Concentration of the cryogenic agent. Greater concentrations produce deeper cooling, accelerating death.
- Life‑stage distribution. Eggs and early‑instar nymphs exhibit higher cold tolerance, requiring longer exposure periods.
- Clutter and hiding places. Dense furnishings limit fog diffusion, potentially leaving refuges that prolong the eradication timeline.
Field studies frequently cite a “seven‑day window” as the point at which most populations are eliminated, with a follow‑up inspection scheduled around day 10 to confirm the absence of survivors. «The efficacy of cold‑fog treatment is maximized when the application is repeated after the initial 72‑hour period, targeting any residual life stages that survived the first exposure.»