The draft genome data for Cimex hemipterus obtained through Illumina HiSeq sequencing were presented. The raw genomic data was deposited in GenBank under BioProject (PRJNA722579) with the BioSample accession number SAMN18780126. Software, including FLASH, SPADES, and QUAST, were used to merge, assemble, and qualify the raw dataset. The assembled genome was available in the Figshare repository. The assembled genomic data was compared to C. hemipterus data obtained using 454 Roche shotgun sequencing (BioProject, PRJNA308532), downloaded from NCBI. The draft genome data from this work demonstrated larger data volumes and an updated assembly of the C. hemipterus genome with better scaffolding compared to genome data obtained from 454 Roche shotgun sequencing.

Population of the tropical bed bug Cimex hemipterus (F.) (Hemiptera: Cimicidae), a temporary ectoparasite on both humans and animals, have surged in many tropical countries. Tropical bed bugs preferences when selecting a suitable harbourage and oviposition site were investigated. Two-choice and three choice colour assays were conducted to determine whether bed bugs will choose black, red or white coloured harbourages. Then, 50 1st instar were reared in containers containing black, red and white (control) paper served as the harbourages and observed for 12 weeks. Both fed and starve male, female and nymph strongly preferred red and black coloured harbourage compared to white coloured harbourage. Oviposition assays showed that female bed bugs prefered to laid their eggs on red coloured harbourages compared to black coloured harbourages. Rearing experiment showed that there was no significant difference (p > 0.05) between final population size of tropical bed bug. However, tropical bed bugs reared in container with red paper (600 ± 89.238) have the highest number of individuals followed by black (473 ± 133.841) and white (485 ± 84.234) paper. Bed bug preference towards coloured harbourage provide useful information for those developing new bed bug control method or improving bed bug infestation monitoring devices.
Populasi pepijat tropika Cimex hemipterus (F.) (Hemiptera: Cimicidae), ektoparasit sementara pada manusia dan haiwan, telah meningkat di banyak negara tropika. Keutamaan pepijat apabila memilih tempat berteduh dan oviposisi yang sesuai dikaji. Ujian warna dua pilihan dan tiga pilihan telah dijalankan untuk menentukan sama ada pepijat akan memilih tempat berteduh berwarna hitam, merah atau putih. Kemudian, 50 instar 1 dibesarkan dalam bekas yang mengandungi kertas hitam, merah dan putih (kawalan) yang berfungsi sebagai tempat berteduh dan diperhatikan selama 12 minggu. Kedua-dua jantan, betina dan nimfa yang diberi makan dan kelaparan sangat menyukai tempat berteduh berwarna merah dan hitam berbanding tempat berteduh berwarna putih. Ujian oviposisi menunjukkan bahawa pepijat betina lebih suka bertelur di tempat berteduh berwarna merah berbanding dengan tempat berteduh berwarna hitam. Eksperimen berteduh menunjukkan bahawa tidak terdapat perbezaan yang signifikan (p > 0.05) antara saiz populasi akhir pepijat tropika. Walau bagaimanapun, pepijat tropika yang dibiak di dalam bekas dengan kertas merah (600 ± 89.238) mempunyai bilangan individu tertinggi diikuti oleh kertas hitam (473 ± 133.841) dan putih (485 ± 84.234). Keutamaan pepijat terhadap tempat berteduh berwarna memberikan maklumat berguna bagi mereka yang membangunkan kaedah baru kawalan pepijat atau memperbaik peranti pemantauan infestasi pepijat.

A study was conducted to investigate the population genetic structure and breeding pattern of 140 tropical bed bugs, Cimex hemipterus (F.) (Hemiptera: Cimicidae), collected from 14 infested sites in major cities in Iraq. The samples were genotyped using a set of 7 polymorphic microsatellite markers. High genetic variety was seen among populations, with an average of 2-9 alleles per locus. The number of alleles across 7 microsatellite loci was between 6 and 18. There was a notable disparity in the alleles per loci when comparing the overall population to those within it. The overall population exhibited an average observed heterozygosity of 0.175 and an average expected heterozygosity of 0.730. Among the population, the average observed heterozygosity was 0.173, while the average expected heterozygosity was 0.673. Analysis of molecular variance (AMOVA) revealed that 93% of the genetic variability was within the populations, and 7% was among them. The genetic differentiation coefficient (FST = 0.045), indicates a low degree of genetic differentiation and a high degree of inbreeding (FIS = 0.761), as indicated by notably significant positive inbreeding coefficients. Admixed individuals were revealed using STRUCTURE and neighbor-joining phylogenetic trees, demonstrating moderate gene flow between populations and a lack of genetic structure in the regional groups. Thus, both active dispersion and human-mediated dispersion possess the potential to influence the low population genetic structure of tropical bed bug C. hemipterus populations in Iraq, which can have implications toward tropical bed bug and management strategies.

With the increase in international travel and trade, in conjunction with the development of insecticide resistance, infestations of Cimex lectularius (L.) and Cimex hemipterus (F.) (Hemiptera: Cimicidae) have resurged globally in the last 2 decades. Recently, it was reported that C. hemipterus was also found in temperate regions, indicating the possibility of its expansion outside tropical regions. Cimex hemipterus has not been officially recorded in Korea since its initial description in 1934. Here, we report the first recent case of C. hemipterus in Korea based on morphological and molecular identification. Partial sequencing of the voltage-sensitive sodium channel gene revealed super-kdr mutations (M918I and L1014F) that are associated with pyrethroid resistance. This case report serves as a warning to intensify the bed bug surveillance system in Korea regarding the presence of C. hemipterus and to prepare effective alternative insecticides for pyrethroids.

The metagenomics dataset presented here is based on bacterial 16S rDNA gene amplicons of DNA extracted from tropical bed bugs (Cimex hemipterus). Amplicon-based sequencing was performed using the Illumina MiSeq platform, and the raw sequence data were analyzed using QIIME (version 2022.8.3). The metagenome sequence comprised ten samples that include C1 (133 511bps), C2 (108 920bps), CH1 (106 562bps), CH2 (101 778bps), P1 (103 618bps), P2 (133 258bps), T1 (113 558bps), T2 (133 952bps), TM1 (125 335bps), and TM2 (118 345bps). The sequence data is readily accessible at the NCBI SRA under bio project PRJNA918835. The most abundant microbial community present in the C. hemipterus is the Proteobacteria, with more than 99% of the abundance.

Bed bugs, Cimex lectularius (L.) (Hemiptera: Cimicidae) and Cimex hemipterus (F.), have become established worldwide in recent years largely due to the development of insecticide resistance. However, limited attention has been given to ongoing morphological and macroevolutionary changes within the species and their populations, which could have implications for their control. Here, we evaluated whether bed bugs of the species C. hemipterus inhabiting different communities in Cape Coast, Ghana are undergoing segregation, which could lead to possible speciation. We also aimed to provide a morphometric description of all nymphal stages. Nine-bed bug populations of C. hemipterus were field-collected in Cape Coast and were subjected to geometric morphometric analysis. The multivariate parameters applied distinguished various populations from each of the locations, indicating the presence of morphologically distinct subpopulations of C. hemipterus. Shape-based segregation and shape changes associated with the insect pronotum (which is an important taxonomic character in the Cimicidae) were evident across the populations. Through this comparative study of C. hemipterus, we showed that possible subpopulations of this bed bug are being spread from Ghana. The nymphal stages (first-fifth) of C. hemipterus were distinguished by the length of the last three antennal segment and pronota width; such information contributes to the taxonomic knowledge of the species.

BACKGROUND: The tropical bed bug, Cimex hemipterus, is an important ectoparasite causing various health problems. This species is mainly confined to tropical regions; however, insecticide resistance, global warming, and globalization have changed its distribution map. Molecular information on pyrethroid resistance, which is essential for the development of control programs, is unknown for C. hemipterus in expanded areas. The present study was designed to determine the permethrin resistance status, characterize the pyrethroid receptor sites in voltage-gated sodium channel (vgsc) gene, and identify the resistance-related mutations in the populations of tropical bed bug in Iran.
METHODS: Live bed bugs were collected, and adults of C. hemipterus were selected for bioassay and molecular surveys. Bioassay was performed by tarsal contact with permethrin 0.75% in mixed-sex of samples. Conventional and quantitative TaqMan and SYBR Green real-time PCR assays were conducted to characterize the vgsc gene and genotypes of studied populations.
RESULTS: In the bioassay tests, the mortality rates were in the range of 30.7-38.7% and 56.2-77.4% in 24 and 48 h, respectively. The knockdown rates of studied populations were in the range of 32.2-46.6% and 61.5-83.8% in the first and second days, respectively. The KT50 and KT90 values in the Cimex lectularius Kh1 strain were presented as 5.39 and 15.55 h, respectively. These values in the selected populations of C. hemipterus varied from 27.9 to 29.5 and from 82.8 to 104.4 h, respectively. Knockdown time ratios (KR50 and KR90) in these populations varied from 5.17 to 6.17-fold compared with those of the C. lectularius Kh1 strain. Fragments of vgsc gene with 355 bp and 812 bp were amplified. Analysis of sequences revealed the A468T substitution, kdr-associated D953G, and super-kdr M918I and L1014F mutations in all populations.
CONCLUSIONS: The specific/sensitive, safe, and rapid diagnostic assays developed in this study are recommended for detection of kdr/super-kdr mutations and frequency of mutant alleles. The presence of super-kdr mutations and high resistance to permethrin in all the populations necessitate the reconsideration of control approaches against C. hemipterus.

This study reports the first baseline information on tropical bed bug, Cimex hemipterus (F.) (Hemiptera: Cimicidae), infestations in Ghana. The purpose of this study was to assess bed bug infestation levels, and the efficacy of locally available insecticides and long-lasting insecticidal nets (LLINs) in controlling field bed bugs populations in the Cape Coast region. A survey was undertaken to assess bed bug infestation levels and current control practices by residents. In total, 205 bed bug affected households were identified in 20 communities and live bed bug infestations were associated with most of these premises. Many homeowners knew of other households (from 1 to 3) with a bed bug infestation. Residents reported itching and swelling of the skin from the bed bug bites and the bites were considered severe. The most common household bed bug control strategy was the application of insecticides. However, LLINs and commercially formulated insecticides commonly used by households (notably chloropyrifos and pyrethroid-based formulations) did not efficaciously suppress field collected strains of C. hemipterus. Using a dipping bioassay, mean mortality ranged from 0 to 60% for eggs, nymphs, and adults, and less than 40% mortality was observed in bed bugs placed on insecticide-treated filter paper. Each LLINs (all are pyrethroid based) produced a mean mortality of less than 20% in adult bed bugs. For a more effective response to the global bed bug resurgence in developing countries, government and supporting agencies need to render assistance to bed bug affected residents through the provision of improved pest management strategies.

We evaluated the influences of insecticide exposure time and mortality assessment intervals on the bioassay results of three insecticide-resistant tropical bed bug Cimex hemipterus (F.) populations (Madam Mo, Tanjong Tokong, and Green Lane). This was achieved using the surface contact method and tested with six commercial insecticide products: Tandem, Temprid SC, Pesguard FG161, Sumithrin, Sumithion, and Phantom applied at label rate on glass petri dishes. Six exposure times (5 min, 10 min, 30 min, 1 h, 4 h, and continuous exposure for 4 or 14 days for Phantom) were tested. A susceptible common bed bug Cimex lectularius L. strain (Monheim) was used as the reference strain as no susceptible C. hemipterus strain exists. In treatment with Temprid SC, the Tanjong Tokong strain showed significantly higher KT50 values at 5, 10, and 30 min exposures than 1 h, 4 h, and continuous exposures. When all resistant populations were evaluated at continuous exposure to Sumithion, they demonstrated moderate resistance levels (RR50 ranged from 6.0 to 7.9), while KT50 and KT95 of other shorter exposure times failed to be generated due to low knockdown rate. Higher mortalities were observed in Tanjong Tokong and Green Lane strains when tested at longer exposure times with Temprid SC, Pesguard FG161, Sumithrin, Sumithion, and Phantom. Better killing effect was observed in the treatment with Temprid SC (Tanjong Tokong and Green Lane strains), Pesguard FG161 (Tanjong Tokong and Green Lane strains), Sumithrin (all C. hemipterus strains), Sumithion (all C. hemipterus strains), and Phantom (all strains tested) at longer mortality assessment intervals. We demonstrated that insecticide exposure time and mortality assessment interval could potentially affect outcomes of product performance evaluations, resulting in underestimation or overestimation of insecticide resistance levels in field populations.

BACKGROUND: The tropical bed bug, Cimex hemipterus, is a serious indoor public health pest in tropical regions causing intense physical discomfort and mental distress to humans. At present, the application of insecticides is the major control strategy. The present study was designed to evaluate the development of resistance and resistance mechanisms in Cimex hemipterus from Kandy district, Sri Lanka.
METHODS: The resistance status of the collected bed bugs was determined against the discriminative dosages of DDT, malathion, propoxur, deltamethrin and permethrin by conducting bioassays according to World Health Organization guidelines. Activities of insecticide metabolizing enzymes, i.e. esterases, glutathione S-transferases (GST) and monooxygenases, and the insensitivity of organophosphate/carbamate target site acetylcholinesterase (AChE), were evaluated by biochemical assays. Regions of the gene of the pyrethroid/DDT target site, the voltage-gated sodium channel regulatory protein (VGSC), were sequenced for possible kdr mutations.
RESULTS: Survival percentages of bed bug population were 71, 68 and 51% for DDT, malathion and propoxur respectively. KT50 and KT90 values, calculated using log-probit mortality curves for deltamethrin were 62.55 and 123.96 h, respectively. These values were much higher for permethrin where KT50 was 201.10 h and the KT90 was beyond the detectable range. Results were compared with previous values reported for the same population in 2002. Resistance to propoxur has increased significantly from 11 to 51% with about a 20-fold increase in the number of individuals with elevated esterase mechanism. No significant change has occurred in malathion and DDT resistance, in GST and monooxygenase activities, and in AChE sensitivity for the past 14 years. Six kdr associated mutations (Y/L995H, V1010L, I1011F, L1014F, V1016E, L1017F/S) and a non-kdr associated mutation (A1007S mutation) were found from the α-region of the VGSC gene. Out of the kdr type mutations, only L1014F has been reported previously form C. hemipterus while the others have been reported from other insects.
CONCLUSIONS: The bed bug population has developed high resistance to propoxur with increased esterase activities. KT50 for deltamethrin and permethrin has increased 125- and 20-fold, respectively, over the period 2002 to 2016. To the authors\' knowledge, this is the first time that the possible involvement of a kdr type mutation in developing pyrethroid resistance in C. hemipterus has been shown in Sri Lanka.