Cimex species are ectoparasites that exclusively feed on warm-blooded animals such as birds and mammals. Three cimicid species are known to be persistent pests for humans, including the tropical bed bug Cimex hemipterus, common bed bug Cimex lectularius, and Eastern bat bug Leptocimex boueti. To date, genomic information is restricted to the common bed bug C. lectularius, which limits understanding their biology and to provide controls of bed bug infestations. Here, a chromosomal-level genome assembly of C. hemipterus (495 Mb [megabase pairs]) contained on 16 pseudochromosomes (scaffold N50 = 34 Mb), together with 9 messenger RNA and small RNA transcriptomes were obtained. In comparison between hemipteran genomes, we found that the tetraspanin superfamily was expanded in the Cimex ancestor. This study provides the first genome assembly for the tropical bed bug C. hemipterus, and offers an unprecedented opportunity to address questions relating to bed bug infestations, as well as genomic evolution to hemipterans more widely.

Bedbugs (Cimex lectularius) are a persistent nuisance pest for humans and their home environment, and may also opportunistically feed on other mammals, including household pets like dogs and cats. NexGard® Combo is a topical endectoparasiticide product for cats combining esafoxolaner, an isoxazoline compound with insecticidal and acaricidal properties, the nematocide eprinomectin and the cestocide praziquantel. The insecticidal efficacy of this product was evaluated in cats experimentally infested with C. lectularius in a blinded, negative controlled and randomized study. Two groups of 7 cats were formed: an untreated control group, and a NexGard® Combo group treated once on Day 0 at the label dose. Cats were then challenged weekly, each with twenty unfed adult C. lectularius, on Days 1, 7, 14, 21 and 28. After close contact with the cat\'s skin for 15 min, live fed C. lectularius were collected and incubated for 96 h. The weekly efficacy evaluations were based on a comparison of the number of surviving bedbugs in the control and the treated group after 48, 72 and 96 h of incubation. The model was demonstrated to be robust as in the control group the average feeding rate after the 15-minute challenge was 94%, and as 96% of incubated bed bugs were alive after 96 hours of incubation. Significant live bedbug reductions were demonstrated in the Nexgard® Combo treated group: after 96 h of incubation, the reductions ranged from 80.6 to 88.0% during the Day 1 to Day 21 period, and dropped to 58% at Day 28.
UNASSIGNED: Efficacité d’une formulation topique associant esafoxolaner, éprinomectine et praziquantel contre les infestations expérimentales par les punaises de lit (Cimex lectularius) chez le chat.
UNASSIGNED: Les punaises de lit (Cimex lectularius) sont une nuisance persistante pour les humains et leur environnement domestique, et peuvent également se nourrir de manière opportuniste d’autres mammifères, y compris les animaux domestiques comme les chiens et les chats. NexGard® Combo est une formulation topique endectoparasiticide pour chats associant l’esafoxolaner, un composé d’isoxazoline à propriétés insecticides et acaricides, le nématodicide éprinomectine et le cestodicide praziquantel. L’efficacité insecticide de ce produit a été évaluée chez des chats infestés expérimentalement par C. lectularius dans une étude en aveugle et randomisée avec contrôle négatif. Deux groupes de 7 chats ont été formés, un groupe témoin non traité et un groupe traité par NexGard® Combo une fois au jour 0 à la dose indiquée sur l’étiquette. Les chats ont ensuite été testés chaque semaine, chacun avec vingt C. lectularius adultes non nourris, les jours 1, 7, 14, 21 et 28. Après un contact étroit avec la peau du chat pendant 15 minutes, les C. lectularius nourris et vivants ont été collectés et incubés pendant 96 heures. Les évaluations hebdomadaires d’efficacité ont été basées sur une comparaison du nombre de punaises de lit survivantes entre le groupe témoin et le groupe traité après 48, 72 et 96 heures d’incubation. Le modèle s’est avéré robuste car dans le groupe témoin, le taux d’alimentation moyen après 15 minutes de contact était de 94 % et 96 % des punaises de lit incubées étaient vivantes après 96 heures d’incubation. Des réductions significatives du nombre de punaises de lit vivantes ont été démontrées dans le groupe traité par Nexgard® Combo : après 96 heures d’incubation, les réductions variaient de 80,6 à 88,0 % pendant la période du jour 1 au jour 21 et ont chuté à 58 % au jour 28.

This study aimed to review published scientific literature on bed bugs in countries where insecticide resistance has been reported worldwide from 2000 to 2021. Electronic databases, including Scopus, PubMed, and WOS, were searched. Out of 606 articles found in the initial search, we selected 57 articles, of which 40 articles had reported on Cimex lectularius (C. lectularius), and 22 papers had reported on Cimex hemipterus (C. hemipterus). Most studies on insecticide resistance were carried out on C. lectularius in North America (14, 35%) and C. hemipterus in Asia (16, 72.7%). The most common method used to detect bed bug resistance to insecticides was toxicological bioassay with an overall random pooled effect size of 0.38 (95% CI: 0.23-0.53) in C. lectularius and 0.46 (95% CI: 0.27-0.65) in C. hemipterus. Resistance to pyrethroids was reported against C. lectularius with an overall pooled effect size of 0.75 (95% CI: 0.56-0.94) and C. hemipterus with an overall pooled effect size of 0.81 (95% CI: 0.57-0.93) in 33.40 (82.5%) and 19.22 (86.3%) published articles, respectively. A very high resistance level to pyrethroids in both studied species was observed, and resistance ratios at the highest level were 76389.3 and 315.5 in C. lectularius and C. hemipterus, respectively. Resistance mechanisms against pyrethroids were reported from most locations except Iran and Thailand, but these mechanisms were not studied in other insecticide groups. These reports indicate that chemical control options for bed bugs are limited. Therefore, a combination of chemical and non-chemical strategies is recommended for bed bug control.

Sperm metabolism is fundamental to sperm motility and male fertility. Its measurement is still in its infancy, and recommendations do not exist as to whether or how to standardize laboratory procedures. Here, using the sperm of an insect, the common bedbug, Cimex lectularius, we demonstrate that standardization of sperm metabolism is required with respect to the artificial sperm storage medium and a natural medium, the seminal fluid. We used fluorescence lifetime imaging microscopy (FLIM) in combination with time-correlated single-photon counting (TCSPC) to quantify sperm metabolism based on the fluorescent properties of autofluorescent coenzymes, NAD(P)H and flavin adenine dinucleotide. Autofluorescence lifetimes (decay times) differ for the free and protein-bound state of the co-enzymes, and their relative contributions to the lifetime signal serve to characterize the metabolic state of cells. We found that artificial storage medium and seminal fluid separately, and additively, affected sperm metabolism. In a medium containing sugars and amino acids (Grace\'s Insect medium), sperm showed increased glycolysis compared with a commonly used storage medium, phosphate-buffered saline (PBS). Adding seminal fluid to the sperm additionally increased oxidative phosphorylation, likely reflecting increased energy production of sperm during activation. Our study provides a protocol to measure sperm metabolism independently from motility, stresses that protocol standardizations for sperm measurements should be implemented and, for the first time, demonstrates that seminal fluid alters sperm metabolism. Equivalent protocol standardizations should be imposed on metabolic investigations of human sperm samples.

Background Bed bugs are common urban pests associated with stress, anxiety, depression, and some reports of suicidality. The emergency department (ED) treats patients with both acute mental illness and bed bug infestations. There have been few studies examining associations between bed bug infestations and mental illness. Methods A case-control study involving 332 adult ED patients infested with bed bugs and 4,952 uninfested control patients matched on sex, age (±1 year at the time of the ED visit), and the specific ED was completed. All clinic encounters occurred in northeast Ohio between February 1, 2011, and February 1, 2017, from a single health system. Univariable and multivariable regression analysis looked for associations between bed bug infestation and different psychiatric diagnoses and medications. Results Bed bug infested patients were more likely than uninfested patients to screen positive for an unsafe home and needing an abuse consult at ED triage (P≤.03 for both). ED psychiatric evaluations were not significantly more common among those with (2.4%) and without (1.3%) bed bugs (P=.14). Bed bug infested patients were significantly more likely to have an ED or inpatient diagnosis of alcohol abuse and psychosis (P≤.03 for both), but not for depression or suicidality. On univariable analysis, among ED patients not admitted to the hospital, bed bug infested patients were more likely to be diagnosed with psychosis or schizophrenia/schizoaffective disease (P≤.02) than uninfested patients. Among ED patients that received an ED or inpatient psychiatric evaluation and were admitted to the hospital, bed bug infested patients were significantly less likely to be diagnosed with depression and suicidality (P≤.03 for both). However, they were not significantly more likely to have insomnia or anxiety. Discussion Among ED patients, bed bug infestations were not associated with an ED or inpatient diagnosis of depression or suicidality. On univariable analysis, some mental health diagnoses such as anxiety and insomnia were more common among ED patients with bed bugs, but these associations were no longer significant on multivariable analysis. These associations likely reflect the complex relationships between socioeconomic factors, health disparities, mental illness, and having a bed bug infestation.

At the beginning of the 21st century, the prevalence of Cimex species (bedbugs) infestation in human dwellings rose exponentially, particularly in the United States. Although there is no evidence that bedbugs transmit diseases to their hosts, they are difficult to eradicate, making them a source of psychological and physical distress and a socioeconomic burden to society. Here, the author describes the case of an eight-year-old boy who presented with widespread, multiple, itchy, red papules surrounded by round patches of erythematous, edematous skin, and was eventually diagnosed with cimicosis (bedbug infestation). Other family members living with the boy showed no clinical signs of bedbug infestation, and the bites on the boy were not in the typical three-row linear configuration associated with bedbug bites-which made this case compelling. Clinical diagnostic characteristics, symptom management, and suggestions on infestation eradication are provided. Biological and epidemiological characteristics of bedbug infestation are also described. Currently, evidence of simple, safe, and effective means of bedbug eradication is lacking.

The symbiotic Wolbachia are the most sophisticated mutualistic bacterium among all insect-associated microbiota. Wolbachia-insect relationship fluctuates from the simple facultative/parasitic to an obligate nutritional-mutualistic association as it was the case of the bedbug-Wolbachia from Cimexlectularius. Understanding this association may help in the control of associated arthropods. Genomic data have proven to be reliable tools in resolving some aspects of these symbiotic associations. Although, Wolbachia appear to be fastidious or uncultivated bacteria which strongly limited their study. Here we proposed Drosophila S2 cell line for the isolation and culture model to study Wolbachia strains. We therefore isolated and characterized a novel Wolbachia strain associated with the bedbug Cimexhemipterus, designated as wChem strain PL13, and proposed Wolbachiamassiliensis sp. nov. strain wChem-PL13 a type strain of this new species from new supergroup T. Phylogenetically, T-supergroup was close to F and S-supergroups from insects and D-supergroup from filarial nematodes. We determined the 1,291,339-bp genome of wChem-PL13, which was the smallest insect-associated Wolbachia genomes. Overall, the wChem genome shared 50% of protein coding genes with the other insect-associated facultative Wolbachia strains. These findings highlight the diversity of Wolbachia genotypes as well as the Wolbachia-host relationship among Cimicinae subfamily. The wChem provides folate and riboflavin vitamins on which the host depends, while the bacteria had a limited translation mechanism suggesting its strong dependence to its hosts. However, the clear-cut distinction between mutualism and parasitism of the wChem in C. hemipterus cannot be yet ruled out.

Introduction Bed bugs are commonly encountered by emergency medical service (EMS) providers. The objective of this study was to determine the frequency with which EMS providers encountered bed bugs, assess their knowledge about bed bugs, and analyze the actions they take after finding bed bugs. Methods We anonymously surveyed 407 EMS providers from 180 EMS agencies in northeast Ohio between September 1, 2018, through March 31, 2019. Results Among the providers surveyed, 21% (n = 84) of the EMS providers reported seeing bed bugs at least monthly, and 6% (n = 24) reported seeing bed bugs at least weekly. Being younger, male, and working in an urban environment (vs. rural) were associated with EMS providers reporting more frequent bed bug encounters (p: ≤.05). The mean level of concern for encountering bed bugs among EMS providers was 3.54 (SD: 1.15; scale: 1 = no concern, 5 = very concerned). Among the EMS providers who reported seeing bed bugs at least monthly, 30% took the affected EMS stretcher out of service when they encounter a bed bug, 43% took the EMS rig out of service, 83% cleaned the EMS stretcher with a disinfectant, and 88% notified the ED that their patient has bed bugs. EMS providers scored poorly (mean: 69% correct responses) in a seven-question assessment of basic bed bug biology and public health. Conclusion Based on our findings, we concluded that EMS knowledge and behavior related to bed bugs are suboptimal.

Cimex lectularius L., the common bed bug, is a hematophagous human ectoparasite. The veterinary drugs, spinosad and fluralaner, were studied for their ability to incapacitate C. lectularius when administered in a blood meal using an artificial feeding system under laboratory conditions. Tested drug doses were based on the reported peak blood levels in animals given the drugs. Spinosad at doses 1,000 ng/mL or higher resulted in 75% or greater bed bug incapacitation (defined as death or immobility). Fluralaner at doses 500 ng/mL or higher had 100% bed bug incapacitation. Both drugs were significantly more effective than controls at these doses (P < 0.001).

There is an ongoing need for safe and effective anti-bedbug compounds. Here, we tested the toxicity of three antimicrobial agents against bedbugs when administered orally. We reveal that doxycycline has direct insecticidal activity at 250 μg/ml (0.025%) that is particularly strong against immature bedbugs and appears to be independent of antimicrobial activity. Future studies to determine the mechanisms behind this property could be useful for the development of orally active insecticides or anti-bedbug therapeutics.