Histamine Excretion by the Common Bed Bug (Hemiptera: Cimicidae)

Effects of aging and cleaning on bed bug (Hemiptera: Cimicidae)-derived histamine

Bed bugs (Cimex lectularius L.) are common indoor pests found in close association with humans. Bed bug feces have been identified as the primary source of indoor environmental histamine, an emerging contaminant that could pose a potential threat to human health. Therefore, it is critical that we understand the stability of histamine in homes, along with mitigation strategies so that we can reduce exposure and potential health risks. In this study we characterized histamine stability over time on 2 surfaces (unfinished wood, fabric), discovering that aging histamine at room temperature, over the course of 9 mo, showed no significant changes in the level of this biogenic amine. As histamine appears slow to degrade on its own, we evaluated the efficacy of various cleaning methods for reducing or removing histamine from these surfaces. The most effective histamine cleaning methods on fabric were bleach, hydrogen peroxide, and a laundry cycle, while multi-purpose cleaner, bleach, and hydrogen peroxide were the most effective on unfinished wood. Overall, histamine reduction was most influenced by more aggressive cleaning methods (hard scrubbing) or cleaners known for removing stains (hydrogen peroxide, bleach). The results of this study will enhance our ability to reduce exposure to this emerging contaminant.

Effects of surface type and distance traveled on the efficacy of a Beauveria bassiana (Hypocreales:Cordycipitaceae)-based biopesticide (Aprehend) for bed bug (Hemiptera: Cimicidae) control

The cryptic behavior that characterizes bed bugs (Cimex lectularius L.) makes them one of the most difficult indoor pests to control. Thus, the use of products with long residual efficacy is a key component of successful bed bug management. Aprehend is a biopesticide for bed bug control, whose active ingredient is the entomopathogenic fungus, Beauveria bassiana. This product shows promise for extended bed bug control against pyrethroid-resistant bed bugs, causing mortality days after contact with the treated surface. However, it is unclear how surface type and distance traveled by bed bugs over a treated surface impact efficacy. Therefore, we evaluated the efficacy of different Aprehend band widths applied to different substrates commonly encountered by bed bugs, looking specifically at average time to mortality and overall mortality. Our findings indicate that exposure to fresh applications of Aprehend resulted in high mortality when bed bugs traveled very short distances (1 cm) over some Aprehend-treated surfaces (vinyl tile and cotton jersey fabric), while exposure to other treated surfaces (unfinished pinewood and painted drywall) resulted in comparatively lower mortality even over longer distances (5 cm). Furthermore, we found that bed bugs crawling on cotton jersey fabric picked up a significantly higher number of spores compared to unfinished pinewood. These results indicate that applications of Aprehend as 5 cm (2 inches) bands according to label recommendations can be effective, although surface type is an important determinator of efficacy. This information will help guide pest management professionals in their use of B. bassiana for bed bug control.

Shifting the paradigm: highlights from 2022 demonstrate broad public health impacts of applied urban entomology

In 2022, the dramatic reduction of applied and extension urban entomology positions was highlighted and widely discussed by seasoned and nascent urban entomologists alike. In fact, many urban entomologists are calling for a "paradigm shift" within the discipline given the reduction in niche urban entomology-specific positions. Specifically, many individuals are insisting that movement toward a framework where urban entomologists address complex, cross-disciplinary issues and advocate for research funding through science policy is critical for the endurance of the discipline. In this new model, the purpose of urban entomology does not necessarily change, but rather expands to attack questions that may be of interest to the broader scientific community. In addition, this paradigm shift would necessitate increased engagement of urban entomologists with bureaucratic and administrative agencies to communicate the importance of urban pest management, especially in a landscape where funding opportunities and endowments have been reduced, reallocated, or eliminated. To reflect the ongoing transformation within the field of urban entomology, the objectives of this review were to highlight papers published in 2022 that exemplify the broader impacts of urban entomological studies and urban pest management. Studies with ties to global public health and Entomological Society of America science policy initiatives are highlighted to encourage urban entomologists to consider the far-reaching influence of their research.

Spatial distribution of histamine in bed bug-infested homes

Histamine is a component of the bed bug aggregation pheromone. It was recently identified as an environmental contaminant in homes with active bed bug infestations, posing a potential health risk to humans via skin contact or inhalation. It remains unclear how histamine is distributed in homes and if histamine can become airborne. In the present study, histamine levels in household dust were quantified from multiple locations within bed bug infested and uninfested apartments. Bed bug population levels were quantified using both traps and visual counts. The amount of histamine detected varied significantly with respect to sampling location, with the highest concentration of histamine quantified from bedding material. Infestation severity did not have a significant effect on histamine quantified at any location. Our results indicate that the bedroom should be the primary focus of histamine mitigation efforts, although histamine can be found throughout the home. Histamine quantified from homes without active bed bug infestations suggests that histamine from previous infestations can persist following pest eradication. These findings highlight the importance of histamine as a potential insect allergen and will be important for the development of targeted mitigation strategies of bed bug histamine.

Volatile Organic Compounds: A Promising Tool for Bed Bug Detection

The recent decades' resurgence of bed bugs as a public health concern in industrialized countries has driven an increased interest on new sustainable insecticide-free methods to monitor and control these ectoparasites. Current methods of detection rely mainly on visual inspection or canine scent detection, which are methods that are time-consuming, require experience, are non-specific or require costly mission repetitions. Volatile organic compounds (VOCs) are considered an environmentally friendly alternative and a promising approach for bed bug detection. An overview of the released literature on VOCs, their chemical characteristics and their role in bed bugs' intra- and inter-species communications allowed us to highlight the identification of 49 VOCs in Cimex lectularius (23 molecules) and C. hemipterus (26), which are emitted by both sexes during diverse compartments including aggregation (46), mating (11), defense (4), etc., and all life stages including exuviae or dead bed bugs as a principal indicator of infestation. The latter has a great importance for application of these semiochemicals in successful detection and control management of bed bugs and to prevent their further dispersion. This approach has the advantage of more reliability compared to conventional detection methods with no need for repeated inspections, household furniture moving or resident rehousing for bed bugs' VOC detection, which are commonly performed by active or passive sampling with absorbing tubes and analyzed by gas chromatography-based analytical platforms.