Bed bugs are resilient household pests. Cold temperatures impact their activity and survival. Understanding how bed bugs react to temperature is important for managing infestations.
Bed Bug Temperature Preferences
Bed bugs thrive in environments with moderate temperatures, between 70 and 80 degrees Fahrenheit (21-27°C). This range supports their rapid development, reproduction, and activity. When temperatures drop below this optimal range, bed bug activity slows considerably.
At temperatures below 61 degrees Fahrenheit (16°C), bed bugs may enter a state of dormancy known as diapause. While they can remain active at temperatures as low as 46 degrees Fahrenheit (7°C), their life cycle and feeding frequency are reduced in cooler conditions. This slowed metabolism allows them to survive for extended periods without a blood meal, but it does not immediately kill them.
Lethal Cold Temperatures for Bed Bugs
To eliminate bed bugs, temperatures must be colder than their preferred living conditions and sustained for a specific duration. Temperatures below 0 degrees Fahrenheit (-18°C) are required to kill all life stages, including eggs, nymphs, and adults. The exposure time needed depends on how cold the environment is.
For instance, exposing them to -16 degrees Celsius (3.2°F) for at least 80 hours can achieve complete mortality of all bed bug life stages. If the temperature is lowered to -20 degrees Celsius (-4°F), the required exposure time decreases to approximately 48 hours. Colder temperatures, below -22 degrees Fahrenheit (-30°C), can achieve mortality within three to four days.
Bed bug eggs, which can tolerate short exposures to temperatures as low as -25 degrees Celsius (-13°F), also succumb to sustained freezing. While bed bugs attempt to lower the freezing point of their body fluids, they are susceptible to prolonged cold. Ensuring the core of infested items reaches and maintains these lethal temperatures is necessary for successful eradication.
Practical Cold Treatment Considerations
Cold temperatures are a method for treating bed bug infestations on certain items. For small, infested belongings like clothing, bedding, or books, placing them in a sealed plastic bag and then into a freezer is a common method. Sealing the items helps prevent bed bugs from escaping and protects them from frost damage.
For this method to be effective, items should remain in a freezer set at 0 degrees Fahrenheit (-18°C) or colder for at least four days. Confirm that the internal temperature of the frozen items, especially denser ones, reaches the lethal threshold, which can be monitored with a remote thermometer.
Relying on outdoor winter temperatures for bed bug control is challenging because consistent lethal cold cannot always be guaranteed. Temperatures can fluctuate, and items placed outdoors may not reach or maintain internal temperatures. Cold treatment is most suitable for isolated items and smaller infestations, rather than widespread problems or large pieces of furniture. For severe infestations, consulting with pest control professionals is recommended.