Widespread Mutations in Voltage-Gated Sodium Channel Gene of Cimex lectularius (Hemiptera: Cimicidae) Populations in Paris

Abstract

Bed bugs, Cimex lectularius and C. hemipterus, are common blood-sucking ectoparasites of humans with a large geographical distribution, worldwide. In France, little is known about the status of bed bugs’ infestation and their resistance to insecticides, particularly, pyrethroids. Here, we aimed to find mutations in the kdr gene, known to be involved in resistance to insecticides. We gathered bed bugs from various infested locations, including 17 private houses, 12 HLM building complex, 29 apartments, 2 EHPAD, and 2 immigrants’ residences. A total of 1211 bed bugs were collected and morphologically identified as C. lectularius. Two fragments of the kdr gene, encompassing codons V419L and L925I, were successfully amplified for 156 specimens. We recorded sense mutation in the first amplified fragment (kdr1) in 89 out of 156 (57%) samples, in which in 61 out of 89 (68.5%) sequences, a change of valine (V) into leucine (L) V419L was observed. Within the second fragment (kdr2), a homozygous mutation was recorded in 73 out of 156 (46.7%) specimens at the codon 925. At this position, 43 out of 73 (58.9%) specimens had a sense mutation leading to the replacement of leucine (L) by isoleucine (I). Among 162 mutant sequences analyzed (89 for the kdr1 fragment and 73 for the kdr2 one), we detected single point mutation in 26.6%, while 73.4% presented the mutation in both kdr1 and kdr2 fragments. All modifications recorded in bed bug populations of Paris are described to be involved in the knockdown resistance (kdr) against pyrethroids.

Bed Bugs (Hemiptera: Cimicidae) Population Diversity and First Record of Cimex hemipterus in Paris

“…The study was carried out from January to June 2019, in collaboration with the Paris municipality’s public health department (SPSE), who provided the preliminary list of infested locations. A total of 62 human dwellings including 17 private houses, 29 apartments, 12 HLM building complexes, 2 EHPAD, and 2 immigrant residences in 15 arrondissements of Paris (1, 2, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, and 20) and 18 suburb cities (Arcueil, Asnieres, Aubervilliers, Bobigny, Chilly-Mazarin, Creteil, Drancy, La Courneuve, Marly-le-Roi, Meudon, Montreuil, Nanterre, Neuilly sur Marne, Nogent-sur-Marne, Pantin, Sarcelles, Stains, and Vincennes) were examined for the presence of bed bugs (the sampling details are given in our previously published article [ 24 ]). Among them, 56 sites were found to be infested, while in 6 places, no bed bug was collected.…”

“…Among them, 56 sites were found to be infested, while in 6 places, no bed bug was collected. A total of 1215 specimens belonging to different life stages (egg, nymph, adult male and female, unfed, and blood-fed) were collected ( Figure 1 ) [ 24 ]. According to specific morphological criteria, the adult specimens were identified, which allowed discrimination between C. hemipterus and C. lectularius [ 18 , 19 ].…”

Survey of bed bug infestations in homeless shelters in southern France

“…Studies on the description of the level of infestation generally focus on the quantity of bed bugs present 29 , 30 , which is a non-discriminating criterion. It is simpler to eradicate bed bugs when they are concentrated in a single, defined area (in this case, the bed).…”

Bed Bugs (Hemiptera, Cimicidae): A Global Challenge for Public Health and Control Management

“…However, they have lesser residual stability than organochlorines and organophosphates [61,68]. Along wide use of mentioned insecticide, several resistance cases of C. lectularius and C. hemipterus populations were reported worldwide [69,70]. One of the first insecticide-resistant cases (DDT) was reported in 1947 in Hawaii [71].…”