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Over the past three decades, the bed bug Cimex lectularius has resurged as a prominent indoor pest on a global scale. Knockdown-associated insecticide resistance (kdr) involving the voltage-gated sodium channel, targeted by organochlorine and pyrethroid insecticides, was first reported in C. lectularius within a few years of the widespread use of dichlorodiphenyltrichloroethane (DDT) and has been implicated as a significant factor contributing to the species’ recent resurgence. Since then, selection with pyrethroid insecticides has intensified, yet little is known regarding its short-term impacts on the frequency of kdr-associated mutations. Here, we report temporal changes in the frequencies of three kdr-associated mutations in C. lectularius populations collected across the USA from two time periods, sampled approximately a decade apart. The results reveal a significant increase in the frequencies of kdr-associated mutations over this period and the absence of the insecticide-susceptible genotype in recent collections. Furthermore, a significant transition was observed toward infestations possessing multiple kdr-associated mutations. These findings suggest that the persistent use of pyrethroid insecticides over the past decade continues to impose strong selection pressure on C. lectularius populations, driving the proliferation of kdr-associated mutations. They demonstrate that, if unabated, strong anthropogenic selection can drive the rapid evolution of adaptive traits.
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Recent Detection of Multiple Populations of the Tropical Bed Bug (Hemiptera: Cimicidae) Exhibiting kdr- Associated Mutations in Hawaii
Abstract 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.
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- PAR ID:
- 10592782
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Journal of Medical Entomology
- Volume:
- 57
- Issue:
- 4
- ISSN:
- 0022-2585
- Format(s):
- Medium: X Size: p. 1077-1081
- Size(s):
- p. 1077-1081
- Sponsoring Org:
- National Science Foundation
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