First Evaluation of Field Evolved Resistance to Commonly Used Insecticides in House Fly Populations from Saudi Arabian Dairy Farms

Abstract

The house fly, Musca domestica L. (Diptera: Muscidae), is one of the major vectors of several pathogens that affect humans and animals. We evaluated the toxicity of eight insecticides commonly used for house fly control using five field populations collected from dairies in Riyadh, Saudi Arabia. Among the five tested pyrethroids, non to moderate resistance was found in adults of both sexes compared to a susceptible strain. Resistance ratios ranged from 0.5- to 7-fold for alpha-cypermethrin, 2- to 21-fold for deltamethrin, 4- to 19-fold for bifenthrin, 1- to 9-fold for cyfluthrin, and 1- to 8-fold for cypermethrin. Among the three tested organophosphates, low to moderate resistance was found among adult flies compared to the susceptible strain, and the resistance ratios ranged from 4- to 27-fold for fenitrothion, 2- to 14-fold for chlorpyrifos, and 3- to 12-fold for malathion. The median lethal times for the tested insecticides were 3–33 h for alpha-cypermethrin, 3–24 h for deltamethrin, 5–59 h for bifenthrin, 1–7 h for cypermethrin, 0.3–7 h for cyfluthrin, 6–36 h for fenitrothion, 2–21 h for chlorpyrifos, and 3–34 h for malathion. This study presents baseline data pertaining to registered public health insecticides, and the results will assist future studies monitoring insecticide resistance, and the planning of effective integrated vector management programs.

Organophosphate Insecticides Resistance in Field Populations of House Flies, Musca domestica L.: Levels of Resistance and Acetylcholinesterase Activity

“…These differences in the resistance levels among the field-collected populations could be attributed to the different patterns of exposure (insecticide type, application method, frequency, and the period of exposure). However, Hafez [14] reported low to moderate resistance levels to fenitrothion (7-27 folds) in house fly field populations collected from dairy farms around Riyadh. These low or moderate levels of resistance to fenitrothion may be attributed to the lack of extensive exposure to insecticides in the dairy farms, unlike the situation of slaughterhouses and vegetable markets in our study.…”

“…Unfortunately, there is no periodic monitoring of insecticide resistance in house fly populations in Riyadh, Saudi Arabia. However, different levels of resistance to the OP insecticides, diazinon (6.8-72 folds) and fenitrothion (7-27 folds), were recorded in house fly field populations in Riyadh [13,14].…”

Alpha-Cypermethrin Resistance in Musca domestica: Resistance Instability, Realized Heritability, Risk Assessment, and Insecticide Cross-Resistance

“…Synthetic pyrethroid insecticides are commonly used to manage vector pests worldwide owing to their efficacy against the pests’ adult and larval stages, lack of persistence in the environment, and low mammalian toxicity [ 1 , 2 ]. However, the indiscriminate use of and over-reliance on these insecticides can increase environmental pollution, negatively affect human health through exposure, and lead to insecticide resistance in the target insect vectors [ 3 , 4 , 5 , 6 , 7 ]. Following the development of insecticide resistance, the public may increase the dosages of insecticides used to suppress resistant insect vectors, thereby compounding the negative effects on the environment and fauna [ 8 , 9 ].…”

“…However, the over-reliance on alpha-cypermethrin has led to resistance development and increased control costs [ 20 , 21 ]. Indeed, alpha-cypermethrin resistance has been reported in various insect pests worldwide [ 5 , 20 , 21 , 22 , 23 , 24 ], forcing insecticide users to increase dosages, leading to the aforementioned negative effects.…”

“…In recent years, low resistance levels to alpha-cypermethrin were observed in Riyadh, Saudi Arabia [ 5 ]. However, data on the (1) risk of alpha-cypermethrin resistance, (2) pace at which alpha-cypermethrin resistance changes, and (3) presence or absence of CR are lacking.…”