Susceptibility of malaysian tropical bed bug cimex hemipterus (F.) (hemiptera: Cimicidae) populations to deltamethrin and propoxur insecticides

Abstract

Bed bugs were collected across Peninsular Malaysia to investigate their resistance to two types of insecticide classes, pyrethroid and carbamate. In this study, commercially-available deltamethrin and propoxur were used to test the resistance status of tropical bed bug, Cimex hemipterus in Malaysia. Their resistance status was evaluated using insecticide-impregnated papers, a bioassay method recommended by the World Health Organization (WHO). Ten adult bed bugs in each population were placed inside the tubes with papers impregnated with 0.05% deltamethrin and 0.1% propoxur. At first, the bugs were exposed for 24 h, then, the exposure period was extended to 14 days. The bioassay was performed in triplicates. The highest resistance level was exhibited by the AR population with a lethal time value (LT50 ) of 466.119 h in the deltamethrin-containing tube. In contrast, propoxur was highly effective against the IP population due to its lethal time value (LT50 = 153.032 h) was the lowest. A significant difference (p < 0.005) was found between insecticide classes and bed bug populations. Mean mortality among AR, SW, HM, PY and PC populations showed a significant difference when exposed to deltamethrin. In conclusion, propoxur showed high efficacy in controlling bed bug populations. However, its efficacy was only at particular places. Meanwhile, a treatment using deltamethrin should be avoided by pest control professionals due to its low efficacy.