Cold tolerance of bed bugs and practical recommendations for control

Bed bugs were exposed to freezing temperatures for various exposure times to determine cold tolerance and mortality estimates for multiple life stages. The mean supercooling point for all bed bug life stages ranged from -21.3°C to -30.3°C, with the egg stage reporting the lowest value. A probit analysis provided a lower lethal temperature (LLT99) of -31.2°C when estimates from all life stages were combined, demonstrating that all stages of bed bugs are not capable of surviving temperatures below body freezing and are therefore freeze intolerant. At conditions above the LLT99, bed bug mortality depended on temperature and exposure time at temperatures above LLT99. Based on our model estimates, survival was estimated for temperatures above -12°C even after 1 wk of continuous exposure. However, exposure to temperatures below -13°C will result in 100% mortality in d to ensure mortality of all life stages. Unfortunately, sublethal exposure to lower temperatures did not prevent subsequent feeding behavior in surviving stages. Practical recommendations for management of potentially infested items are discussed.