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Background: Cimex lectularius L. (bed bug) (Hemiptera: Cimicidae) is a serious indoor pest worldwide, and this nuisance needs to be controlled using different methods in integrated pest management (IPM). Beauveria bassiana (Bals.‐Criv.) Vuill. (Hypocreales: Cordycipitaceae) kills bed bugs, and insect pathogenic fungi may be utilized to control bed bugs in IPM. To increase knowledge of this methodology, forced exposure experiments were conducted with different formulations, doses, and substrates, using bed bugs in variable physiological states. Results: Both oil‐ and water‐formulated fungal products showed significant improvement when conidial concentrations were raised in five steps from 0.02 to 2.0%. At low concentrations (0.02% in water) effects from substrate and application strategy were observed. Application on soft substrates (cotton and polyester) yielded significantly higher bed bug mortality rates than on harder substrates (paper, wood, and linoleum) with a final mortality of 35–63% against 8–10%. Multiple applications over time also improved B. bassiana's ability to kill bed bugs, and at low concentrations only a triple application on cotton showed 100% final mortality. Bed bug age and reproductive status significantly affected survival. Older and reproducing individuals showed higher mortality compared to newly emerged adults. Differences in feeding status also yielded differences in mortality timing, but only minor differences in final mortality rates. Egg production and hatching success were significantly reduced by some treatments. Conclusion: B. bassiana appears to be an asset in the fight against bed bugs. Substrate, dosage, application strategy, and bed bug physiology are important factors to consider for optimal efficacy and safe indoor control with insect pathogenic fungi. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In the last few years, the bed bug Cimex lectularius has been an increasing problem worldwide, mainly due to the development of insecticide resistance to pyrethroids. The characterization of resistance alleles is a prerequisite to improve surveillance and resistance management. To identify genomic variants associated with pyrethroid resistance in Cimex lectularius, we compared the genetic composition of two recent and resistant populations with that of two ancient‐susceptible strains using a genome‐wide pool‐seq design. We identified a large 6 Mb "superlocus" showing particularly high genetic differentiation and association with the resistance phenotype. This superlocus contained several clustered resistance genes and was also characterized by a high density of structural variants (inversions, duplications). The possibility that this superlocus constitutes a resistance "supergene" that evolved after the clustering of alleles adapted to insecticide and after reduction in recombination is discussed. [ABSTRACT FROM AUTHOR]

Bed bugs, Cimex lectularius L. and C. hemipterus (F.) (Hemiptera: Cimicidae) are hematophagous ectoparasites of humans. Since the resurgence of bed bugs in the late 1990s there has been a corresponding emphasis on development and implementation of integrated pest management (IPM) programs to manage infestations. One critical requirement of IPM is the ability to detect and monitor the target pest. We outline and describe the majority of all known existing devices and technologies developed for bed bug detection and monitoring as well as much of the underlying science. Almost 40 detection and monitoring products have flooded the marketplace, but for various reasons, including price, size, complexity and lack of independent scientific evaluation, they have not been widely adopted for IPM in structures. One product, the ClimbUp® Insect Interceptor, has nine competitors that utilize a similar design. This review also discloses many other technologies and products that are either too expensive or too impractical for use as either consumer or industrial products. We conclude that there is a critical need for inexpensive and effective detection and monitoring traps and lures suitable for widespread adoption by the urban pest control industry. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The bacterium Burkholderia multivorans is an opportunistic nosocomial pathogen of humans. A previous study reported molecular detection of this bacterium in several specimens of the common bed bug (Cimex lectularius L.) collected from an elderly care facility in the U.S.A., raising questions about the possibility of vector‐borne transmission. However, the ability of B. multivorans to colonize bed bugs and the ability of bed bugs to transmit the bacteria both remained untested. To resolve this knowledge gap, here we performed a set of experiments to examine the persistence and shedding of B. multivorans following ingestion by bed bugs in a blood meal. We isolated viable B. multivorans from the bodies of bed bugs for up to 13 days post‐ingestion, but bacterial load substantially diminished over time. By 16 days post‐ingestion, the bacteria could not be isolated. Further, B. multivorans was not shed in the saliva of infected bugs during feeding nor was it transmitted vertically from infected insects to their progeny. Based on these results, significant biological or mechanical transmission of B. multivorans to humans by bed bugs appears unlikely. Nonetheless, some viable bacteria were passively shed into the environment through defecation, a process which could potentially contribute to transmission through indirect contamination under rare circumstances. [ABSTRACT FROM AUTHOR]

Aims: To evaluate whether bed bugs are associated with allergic reactions in patients seen in the emergency department (ED). Methods and Results: This retrospective study included data from 9 EDs in Ohio between February 2011 and February 2017. The study comprised 332 patients with bed bug infestation matched 1:15 with 4952 control patients without bed bugs on the basis of age, sex and the presenting ED. Compared with uninfested patients, patients infested with bed bugs were more likely to have an ED or inpatient diagnosis of pruritus, hives or urticaria (odds ratio [OR], 9.12 [95% CI, 3.41‐24.42]) and to be treated in the ED with an antihistamine (OR, 3.20 [95% CI, 1.87‐5.50]) or albuterol (OR, 1.59 [95% CI, 1.07‐2.36]) (P ≤.02 for all). There were no significant differences in the rates of anaphylaxis and angioedema diagnosed in patients with and without bed bugs, which occurred in <1% in both groups. Conclusion: Bed bug–infested patients are more likely to be diagnosed and treated for itchy cutaneous rashes, but are not clearly associated with more severe allergic reactions. [ABSTRACT FROM AUTHOR]

Arthropods are the cause of considerable human morbidity. In spite of numerous text books and reviews published on arthropods of medical importance, this is the first paper in the world to present a comprehensive review of specimens sent to a medical entomology laboratory over an extended period. The Department of Medical Entomology at Westmead Hospital is the New South Wales reference laboratory for arthropods of medical importance. In the years 1988–2017, there were 5655 samples submitted for identification. Some 25 orders, 188 families and 177 different genera were recorded, with 170 unique species. The most common specimens included the Australian paralysis tick Ixodes holocyclus (708 specimens submitted), the bird mite Ornithonyssus bursa (506), bed bugs Cimex spp. (149), moth flies Clogmia spp. (135), head lice Pediculus capitis (105), pubic lice Pthirus pubis (91) and scabies Sarcoptes scabiei (57). In 1211 samples submitted, there was no evidence for any life stages of arthropods. For these common samples, data analysed included yearly and seasonal trends, female vs. male patient submissions and the age classes of the patients. Some species such as I. holocyclus, O. bursa, Cimex spp., Clogmia spp. and P. capitis demonstrated strong seasonal trends. In the case of the female vs. male patients, there were significant differences in submissions with O. bursa, P. capitis, P. pubis and with the samples containing no arthropod evidence. Of these, only with P. pubis did more males submit than females. Younger ages classes (<10 years) were more associated with I. holocyclus and P. capitis, older patients >70 years) with scabies, mature females (50–69 years) with samples containing no evidence of arthropods and middle‐aged adults (40–69) with the remainder of the common samples. Key diagnostic features are included for some of the more challenging arthropod species to distinguish and as well as case studies provided of situations involving unique or unusual infestations. The data provides useful information on the risks that arthropods of medical importance pose to the community and will refine educational programs. [ABSTRACT FROM AUTHOR]

Aims: To investigate the immunoglobulin (Ig) G response after being fed upon by Cimex lectularius L. Methods and Results: Participants were fed upon by three male C lectularius insects weekly for a month. Blood was obtained before the feeding and at the last feeding, which was used for immunoblots against bed bug salivary gland extract, with antihuman Immunoglobulin G (IgG) secondary antibodies. No consistent IgG changes developed in 11 humans serially fed upon by C lectularius. Two participants had new IgG responses to proteins at molecular weights of approximately 12‐13 kDa, and one had an IgG response to a protein at approximately 40 kDa. At the last study visit, more intense IgG bands to proteins at molecular weights of 12‐13 kDa had developed in 55% of participants (6/11) and at molecular weights of ≈30, ≈40 and ≈70 kDa in 45% (5/11) compared with the first study visit. Nitrophorin and apyrase were the most common C lectularius proteins identified with liquid chromatography‐tandem mass spectrometry in both crushed bed bug salivary gland extract and post–bed bug feeding extract. Conclusions: Human participants did not have consistent IgG responses to crushed C lectularius salivary gland extract. [ABSTRACT FROM AUTHOR]

Bedbugs, Cimex lectularius, have re‐gained their status as economically important insects in many parts of the world and, consequently, re‐attracted research into their biology. Standardizing age, feeding and mating status of experimental animals requires easy and reliable identification of the nymphal sex. Here, we show the angle of the pointedness of the abdomen to be a reliable sex marker in nymphal stage 5, as well as the shape of the 9th sternite, allowing rapid nymph sorting by sex. The sexual dimorphism was driven by males, not females, departing from the larval growth trajectory. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Bed bugs, Cimex lectularius L., have become one of the most difficult urban pests to control. Steam treatment is reported to be an effective method to kill bed bugs and is considered to be an important component of bed bug integrated pest management (IPM). We evaluated and compared the efficacies of two affordable consumer‐grade commercial steamers and a commonly used professional‐grade steamer for killing bed bugs. RESULTS: In laboratory experiments, the consumer‐grade steamers at affordable prices achieved the same high control efficacy as the professional‐grade steamer for treating bed bugs exposed on mattresses (100% bed bug mortality for all steamers), located beneath a fabric cover (>89% bed bug mortality for all steamers), or hiding in cracks (100% bed bug mortality for all steamers). Bed bugs located behind a leather cover did not suffer significant mortality from steam treatment regardless of the type of steamers used and the treatment duration. CONCLUSION: Proper use of steamers can kill all life stages of bed bugs. Affordable consumer‐grade steamers are as effective as professional‐grade steam machines for eliminating bed bugs resting on mattresses and hiding behind fabric materials or in cracks. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Bed bugs ( Cimex lectularius L.) have returned as a nuisance pest worldwide. Their ability to withstand different types of environmental stress should be explored in order potentially to increase the efficiency of control methods. RESULTS Immediate and long-term effects of exposure to temperatures from 0 to −10 °C for 1, 2 and 3 weeks are reported. Fifth-instar nymphs and adults were exposed to constant or fluctuating temperatures. Increased cold and extended time yielded higher mortality; nymphs were more resilient than adults at the shorter durations of exposure. At intermediate temperatures, mortality was higher at constant compared with fluctuating temperatures, whereas all individuals died after 3 weeks of exposure to −7 °C. The success among survivors after cold treatment was also affected in terms of reduced egg production, hatching success and the ability of fifth-instar nymphs to advance into the adult stage; however, nymphs produced after cold treatment developed normally. CONCLUSIONS Detrimental effects of prolonged exposure to low temperatures were seen in bed bugs both during and after cold treatment. The results suggest that temperatures below −7 °C can be applied by laymen to control this pest in small items if available treatment time is of less concern. © 2016 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND The global prevalence of Cimex lectularius infestations has challenged current intervention efforts, as pyrethroid resistance has become ubiquitous, availability of labeled insecticides for bed bugs is limited, and non-chemical treatment options, such as heat, are often unaffordable. We evaluated representative insecticides toward the goal of developing a novel, ingestible liquid bait for hematophagous arthropods. RESULTS LC50 values were estimated for adult males and first instar nymphs of an insecticide-susceptible strain for abamectin, clothianidin, fipronil and indoxacarb, after ingestion from an artificial feeder. LD50 values were calculated based on the ingested blood volume. Ingested abamectin, clothianidin and fipronil caused rapid mortality in both life stages. Fipronil was ∼43-fold more effective by ingestion than by topical application. Indoxacarb and its bioactive metabolite decarbomethoxylated JW062 ( DCJW) were ineffective at causing bed bug mortality even at concentrations as high as 1000 ng mL−1 blood. CONCLUSIONS Fipronil, clothianidin and abamectin have potential for being incorporated into a liquid bait for bed bug control; indoxacarb and DCJW were not effective. Bed bugs are a good candidate for an ingestible liquid bait because systemic formulations generally require less active ingredient than residual sprays, they remain contained and more effectively target hematophagous arthropods. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND The resistance of bed bugs ( Cimex lectularius L.) to chemical insecticides has motivated the development of non-chemical control methods such as heat treatment. However, because bed bugs tend to hide in cracks or crevices, their behavior incidentally generates a thermally insulated microenvironment for themselves. Bed bugs located on the outer surface of luggage are less insulated and potentially more vulnerable to brief heat treatment. RESULTS Soft-sided suitcases with adult male bed bugs on the outside were exposed to an air temperature of 70-75 °C. It took 6 min to kill all of the bed bugs, even those that had concealed themselves under zipper flaps or decorative piping. During heating, only one bed bug (out of 250 in total) moved into the luggage (through a closed zipper). Over long periods of time (24 h) at room temperature, adult male bed bugs on the exterior of luggage only infrequently moved inside; only 3% (5/170) had moved inside during 24 h. CONCLUSIONS Brief exterior heat treatment of luggage is a promising way to reduce the spread of bed bugs being transported on the outer surface of luggage. This treatment will not kill bed bugs inside the luggage, but could be a component of integrated management for this pest. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Pyrethroid resistance in the common bed bug, Cimex lectularius L., has been reported worldwide. An important resistance mechanism is via knockdown resistance ( kdr) mutations, notably V419L and L925I. Information regarding this kdr-type resistance mechanism is unknown in Australia. This study aims to examine the status of kdr mutations in Australian C. lectularius strains. RESULTS Several modern field-collected strains and museum-preserved reference collections of Australian C. lectularius were examined. Of the field strains (2007-2013), 96% had the known kdr mutations ( L925I or both V419L/ L925I). The 'Adelaide' strain (2013) and samples from the preserved reference collections (1994-2002) revealed no known kdr mutations. A novel mutation I936F was apparent in the insecticide-resistant 'Adelaide' strain, one strain from Perth (with L925I) and the majority of the reference collection specimens. The laboratory insecticide-resistant 'Sydney' strain showed a mixture of no kdr mutations (20%) and L925I (80%). CONCLUSION The novel mutation I936F may be a kdr mutation but appeared to contribute less resistance to the pyrethroids than the V419L and L925I mutations. The detection of high frequencies of kdr mutations indicates that kdr-type resistance is widespread across Australia. Hence, there should be a reduced reliance on pyrethroid insecticides and an integrated management approach for the control of C. lectularius infestations. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Insecticide resistance in the common bed bug, C imex lectularius Linnaeus has been suspected in Australia with anecdotal reports of poor product performance. To investigate this possibility, LD50 values were determined via topical application of technical grade permethrin, deltamethrin, bendiocarb, pirimiphos-methyl and imidacloprid serially diluted in acetone to a suspected resistant field-collected strain and a susceptible laboratory strain. All compounds tested against the susceptible strain were efficacious. However, for the field strain, only pirimiphos-methyl and imidacloprid showed high levels of activity. Resistance was confirmed in the field-collected strain to the pyrethroids and bendiocarb, but not to pirimiphos-methyl or imidacloprid. Resistance factors ('resistant' LD50/susceptible LD50) for each compound were: permethrin ≈ 1.235 million, deltamethrin ≈ 370 000, bendiocarb ≈ 250, pirimiphos-methyl = 2.6, imidacloprid = 2.6. Bendiocarb, permethrin and deltamethrin all failed to return greater than 60% mortality at the maximum dose of 100 μg/μ L. This research has significant operational implications for bed bug control and the registration process of new products in Australia. [ABSTRACT FROM AUTHOR]

A large-arena bioassay is used to examine sex differences in spatiotemporal patterns of bed bug Cimex lectularius L. behavioural responses to either a human host or CO2 gas. After release in the centre of the arena, 90% of newly-fed bed bugs move to hiding places in the corners within 24 h. They require 3 days to settle down completely in the arena, with generally low activity levels and the absence of responses to human stimuli for 5 days. After 8 - 9 days, persistent responses can be recorded. Sex differences are observed, in which females are more active during establishment, respond faster after feeding, expose themselves more than males during the daytime, and respond more strongly to the host signal. The number of bed bugs that rest in harbourages is found to vary significantly according to light setting and sex. Both sexes stay inside harbourages more in daylight compared with night, and males hide more than females during the daytime but not during the night. The spatial distribution of the bed bugs is also found to change with the presence of CO2, and peak aggregation around the odour source is observed after 24 min. Both male and female bed bugs move from hiding places or the border of the arena toward the centre where CO2 is released. Peak responses are always highest during the night. Bed bug behaviour and behaviour-regulating features are discussed in the context of control methods. [ABSTRACT FROM AUTHOR]

A blood-feeding system that utilizes a small amount of whole heparinized human blood in parafilm bags is described in detail, and similarities and differences between artificially fed and naturally rodent-fed bed bugs (Hemiptera: Cimicidae) are discussed. Blood with high levels of heparin (10%) was unsuitable for artificial colony rearing, whereas bed bugs fed on 1% heparinized blood and those that naturally ingested rat blood completed their lifecycle with similar stage structures over time, with no significant differences in mortality. No differences in feeding efficiency or fertility were found in a direct comparison of bed bugs maintained under each of these two treatments, but analysis of the full lifecycle revealed that artificially fed bed bugs became significantly smaller and laid fewer eggs than rodent-fed bed bugs. The level of membrane stretching regulated the number of bed bugs that fed. When the membrane was stretched to twice its length and width, 96% of bed bugs successfully fed through the parafilm. Whole heparinized blood that was stored at 6 °C for ≥ 14 days failed to retain its nutritional value and the amount of blood consumed and number of consecutive moults were significantly reduced. [ABSTRACT FROM AUTHOR]

Effects of host availability and feeding period on bed bugs, Cimex lectularius (L.) (Hemiptera: Cimicidae), were measured. Population growth and the potential harmful effect of bed bug populations on human hosts were modelled. Bloodmeal sizes were affected by both feeding length and frequency, with >2-fold difference between insects fed daily or weekly. Blood consumption increased >2-fold between bed bugs fed occasionally and often, and 1.5-fold between occasional and daily feeding. Bed bugs fed more often than once a week, potentially every 2-4 days. Egg production was associated with nutrition, being strongly correlated with blood consumption in the previous week. Bed bug populations can grow under different feeding regimes and are hard to control with <80% mortality. Bed bugs can survive and grow even in locations with a limited blood supply, where bed bug persistence may be important for the continual spread of populations. Persistence in non-traditional locations and a potential association with human pathogens increase the health risks of bed bugs. Potential blood loss as a result of a bed bug can have serious consequences because uncontrolled populations can reach harmful levels in 3-8 months. The reproduction potential of bed bug populations suggests serious consequences to human health and the need for efficacious control measures. [ABSTRACT FROM AUTHOR]

BACKGROUND: Bed bugs ( Cimex lectularius L.) have become a common insect pest in urban areas and are often difficult to manage. Eradication is made more problematic by widespread insecticide resistance, raising interest in alternative control products. Juvenile hormone analogs (JHAs) such as methoprene and hydroprene are relatively harmless to non-arthropods and have proved to be effective against other urban insect pests. Two JHA products (Gentrol® and Precor®, Central Life Sciences, Schaumburg, IL) were tested for efficacy against various bed bug stages as direct spray and as dry residue using three bed bug strains. RESULTS: At 1× and 2× the label rate, Precor® [active ingredient ( S)-methoprene] had no significant effect on the development or fecundity of bed bugs. At 2× the label rate, confinement to residues of Gentrol® [active ingredient ( S)-hydroprene] had no significant effect, but residues at 3× and 10× the label rate caused a reduction in fecundity and impaired development. Field strains were more susceptible to the reproductive effects of ( S)-hydroprene than a long-maintained laboratory strain. CONCLUSIONS: While JHAs are attractive alternatives for pest management because of their inherent safety and distinct mode of action, these JHA formulations would have little impact on bed bug populations without relabeling to allow for higher application rates. Copyright © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A global resurgence of bed bugs (Hemiptera: Cimicidae) has led to renewed scientific interest in these insects. The current bed bug upsurge appears to have started almost synchronously in the late 1990s in Europe, the U.S.A. and Australia. Several factors have led to this situation, with resistance to applied insecticides making a significant contribution. With a growing number of insecticides (DDT, carbamates, organophosphates etc.) being no longer available as a result of regulatory restrictions, the mainstay chemistry used for bed bug control over the past few decades has been the pyrethroid insecticides. With reports of increasing tolerance to pyrethroids leading to control failures on the rise, containing and eradicating bed bugs is proving to be a difficult task. Consequently, several recent studies have focused on determining the mode of action of pyrethroid resistance in bed bug populations sourced from different locations. Correct identification of the factor(s) responsible for the increasing resistance is critical to the development of effective management strategies, which need to be based, wherever possible, on firm scientific evidence. Here we review the literature on this topic, highlighting the mechanisms thought to be involved and the problems currently faced by pest control professionals in dealing with a developing pandemic. [ABSTRACT FROM AUTHOR]

The article presents a study on the development of chlorfenapyr to control bed bug populations. It sates that laboratory assays were used to measure the effectiveness of two chlorfenapyr-based formulation such as aerosol and water-based formulation. Furthermore, the study shows that aerosol formulation of chlorfenapyr caused faster mortality than water-based formulation. It says that long residual activity of chlorfenapyr is suitable for bed bug controls.

This study of the bed bug, Cimex lectularius, examines tolerance of adult females to extremes in temperature and loss of body water. Although the supercooling point (SCP) of the bed bugs was approximately −20°C, all were killed by a direct 1 h exposure to −16°C. Thus, this species cannot tolerate freezing and is killed at temperatures well above its SCP. Neither cold acclimation at 4°C for 2 weeks nor dehydration (15% loss of water content) enhanced cold tolerance. However, bed bugs have the capacity for rapid cold hardening, i.e. a 1-h exposure to 0°C improved their subsequent tolerance of −14 and −16°C. In response to heat stress, fewer than 20% of the bugs survived a 1-h exposure to 46°C, and nearly all were killed at 48°C. Dehydration, heat acclimation at 30°C for 2 weeks and rapid heat hardening at 37°C for 1 h all failed to improve heat tolerance. Expression of the mRNAs encoding two heat shock proteins (Hsps), Hsp70 and Hsp90, was elevated in response to heat stress, cold stress and during dehydration and rehydration. The response of Hsp90 was more pronounced than that of Hsp70 during dehydration and rehydration. Our results define the tolerance limits for bed bugs to these commonly encountered stresses of temperature and low humidity and indicate a role for Hsps in responding to these stresses. [ABSTRACT FROM AUTHOR]