Developing effective alternative approaches for disinfesting bed bugs from residential spaces requires a balance between obtaining complete insect mortality, while minimizing costs and energy consumption. One method of disinfestation is the application of lethal high temperatures directly to rooms and contents within a structure (termed whole-room heat treatments). However, temperature and time parameters for efficacy in whole-room heat treatments are unknown given the slower rate of temperature increase and the probable variability of end-point temperatures within a treated room. The objective of these experiments was to explore requirements to produce maximum mortality from heat exposure using conditions that are more characteristic of whole-room heat treatments. Bed bugs were exposed in an acute lethal temperature (LTemp) trial, or time trials at sub-acute lethal temperatures (LTime). The lethal temperature (LTemp₉₉) for adults was 48.3 °C, while LTemp₉₉ for eggs was 54.8 °C. Adult bed bugs exposed to 45 °C had a LTime₉₉ of 94.8 min, while eggs survived 7 h at 45 °C and only 71.5 min at 48 °C. We discuss differences in exposure methodologies, potential reasons why bed bugs can withstand higher temperatures and future directions for research.

Bed bugs, Cimex lectularius L., are a major pest in the urban environment. Their presence often results in physical, psychological, and financial distress of homeowners and apartment dwellers. Although many insecticide bioassays have been performed on this pest, little attention has been paid to bed bug feeding status, which is closely linked to metabolism, molting, and mass. Therefore, we evaluated the toxicity of topically applied deltamethrin on insecticide susceptible adult male bed bugs fed 2 d, 9 d, and 21 d prior to testing. When toxicity was evaluated on a “per-bug” basis, there was no difference between 2 d [LD₅₀ = 0.498 (0.316 − 0.692) ng·bug⁻¹] and 9 d [LD₅₀ = 0.572 (0.436 − 0.724) ng·bug⁻¹] starved bugs, while 21 d starved bugs had a significantly lower LD₅₀ [0.221 (0.075 − 0.386) ng·bug⁻¹]. When toxicity was evaluated in terms of body mass, 9 d starved bugs had the highest LD₅₀ values [0.138 (0.102 − 0.176) ng·mg⁻¹], followed by 2 d starved bugs [0.095 (0.060 − 0.134) ng·mg⁻¹], and then 21 d starved bugs [0.058 (0.019–0.102) ng·mg⁻¹]; the LD₅₀ values of 2 d and 9 d starved bugs were significantly different from 21 d starved bugs. These results indicate that feeding status plays an important role in the toxicity of deltamethrin. In addition, the lack of differences between 2 d and 9 d starved bugs indicate that the blood meal itself has little impact on tolerance, but rather it is some physiological change following feeding that confers increased tolerance to bed bugs.