Recent Detection of Multiple Populations of the Tropical Bed Bug (Hemiptera: Cimicidae) Exhibiting kdr-Associated Mutations in Hawaii

Abstract

<jats:title>Abstract</jats:title> <jats:p>In recent years, bed bugs have experienced a remarkable resurgence on a near global scale. While reports have primarily focused on the common bed bug, Cimex lectularius (L.), which has resurged largely in temperate regions, in tropical regions the tropical bed bug, Cimex hemipterus (F.) (Hemiptera: Cimicidae), has reemerged as well. Recent reports of C. hemipterus introductions to subtropical and temperate regions, outside of the species natural distribution, suggest the potential for establishment and further spread. Establishment may be aided by insecticide resistance mechanisms, such as the presence of knockdown resistance (kdr)-associated mutations, which potentially confer resistance to pyrethroid, pyrethrin, and organochloride insecticides. Here, we present the first report of the detection and likely establishment of C. hemipterus in Honolulu, Hawaii, from samples collected in 2009 and 2019. Furthermore, through partial sequencing of the voltage-gated sodium channel, we report the presence of kdr-associated mutations in all samples. These findings have implications for the implementation of control strategies aimed at eradicating infestations.</jats:p>

High Levels of Pyrethroid Resistance and Super-Kdr Mutations in the Populations of Tropical Bed Bug, Cimex Hemipterus, in Iran

“…The aim of this investigation was to determine the kdr mutation in different populations of tropical bed bug, and, therefore, several point mutations, including A468T, D953G, M918I, and L1014F, were identi ed. Similar to the nding of our study, previous investigations have documented the D953G, M918I, and L1014F mutations in other populations of bed bugs and other insects [9,13,15,25,60,61]. However, owing to the mechanisms of post-transcriptional regulatory variation in organisms, mRNA editing is possible [66].…”

Cuticle thickening associated with fenitrothion and imidacloprid resistance and influence of voltage‐gated sodium channel mutations on pyrethroid resistance in the tropical bed bug, Cimex hemipterus

“…Since the initial characterization of L1014F and M918T various replacements at these two sites, L1014C/H/S/W and M918I/L/T/V, have also been recorded 40,44 . Both the L1014F and M918I mutations found in the current study have also been reported previously in pyrethroid‐resistant strains of C. hemipterus 28–31 . The current study suggests that the presence of double VGSC L1014F + M918I mutations is likely superior to the presence of enhanced cuticle thickness in conferring pyrethroid resistance in C. hemipterus because no mortality was observed on deltamethrin residue when tested against SEL_MY, PEN2_MY and KUL_MY strains with different cuticle thicknesses.…”

“…Regardless of this finding, no molecular information of a pyrethroid‐susceptible strain of C. hemipterus is currently available. Thus far, nine putative kdr mutations have been recorded in C. hemipterus , namely L899V, M918I, D953G, L1014F, Y/I995H, V1010L, I1011F, V1016E and L1017F/S, 28–31 as opposed to only two documented kdr mutations, V419L and L925I, in C. lectularius 48 . I1011T is a novel mutation that has not been described in bed bugs.…”

“…Since the first discovery of kdr mutations in the housefly ( Musca domestica ), further studies have identified several additional mutations in VGSC of various resistant insect strains 24,26 . In bed bugs, two kdr mutations have been described in C. lectularius , 27 and nine putative kdr mutations have been documented in C. hemipterus 28–31 . Nevertheless, despite the relatively large number of reported putative kdr mutations in C. hemipterus , no pyrethroid‐susceptible genotype has been documented, mainly due to the absence of an established insecticide‐susceptible strain of C. hemipterus .…”

Early evidence of establishment of the tropical bedbug (Cimex hemipterus) in Central Europe

“…The COI haplotype found in infestations sampled in the Czech Republic and Slovakia was previously reported across many countries and appears to be the most common COI variant of C. hemipterus , at least in Asia. Similarly, the sodium channel variant, containing M918I and L1014F mutations, has been reported multiple times, from India and Australia (Dang et al ., 2015b), and from China (Zhao et al ., 2020), but not in Hawaii (Lewis et al ., 2020) or Sri Lanka (Punchihewa et al ., 2019). Although the country of origin cannot be pinpointed accurately at this time, the genetic uniformity of the Czech and Slovakian infestations may suggest a single introduction followed by spread.…”