Organophosphate and Pyrethroid Resistance Status of Invasive Aedes aegypti (Diptera: Culicidae) from Iran

Tahereh Sadat  Asgarian; Ahmadali  Enayati; Seyed Hassan  Moosa-Kazemi; Morteza  Zaim; Seyed Aghil  Jaberhashemi; Zahra  Saeidi; Mohammad Ali  Oshaghi; Mohammad Mehdi  Sedaghat

doi:10.18502/jad.v18i4.19337

Tahereh Sadat Asgarian Department of Vector Biology and Control of Diseases, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
Ahmadali Enayati Department of Medical Entomology and Vector Control, School of Public Health and Health Sciences Research Center, Mazandaran University of Medical Sciences, Sari, Iran
Seyed Hassan Moosa-Kazemi Department of Vector Biology and Control of Diseases, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
Morteza Zaim Department of Vector Biology and Control of Diseases, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
Seyed Aghil Jaberhashemi Infectious and Tropical Diseases Research Center, Hormozgan Health Institute, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
Zahra Saeidi Department of Vector Biology and Control of Diseases, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
Mohammad Ali Oshaghi Department of Vector Biology and Control of Diseases, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
Mohammad Mehdi Sedaghat Department of Vector Biology and Control of Diseases, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran

DOI: https://doi.org/10.18502/jad.v18i4.19337

Keywords: Aedes aegypti; Insecticide resistance; Dengue fever; Vector control; Iran

Abstract

Background: The growing concerns regarding the recent invasion of Aedes aegypti in Iran and the potential outbreak of dengue fever, chikungunya and Zika viruses in the country highlight the importance of assessing the susceptibility of this vector to different insecticides.

Methods: The study assessed the resistance status of Ae. aegypti resistance to insecticides such as deltamethrin, permethrin, malathion, and temephos in Bandar Abbas City, Hormozgan Province, Iran. The research followed WHO standard testing procedures for adult mosquitoes. Adult susceptibility tests were conducted using 1X the discriminating concentrations to determine the frequency and status of insecticide resistance. Additionally, 5X and 10X the discriminating concentration were used to evaluate the intensity of resistance. Larval susceptibility to temephos was tested using concentrations of 156.25, 31.25, 6.25, 1.25, and 0.25 mg/l of temephos.

Results: Adults were resistant to all three tested insecticides at WHO-recommended diagnostic concentrations (DCs). In terms of resistance intensity, Ae. aegypti exhibited low-intensity resistance to malathion and deltamethrin, while resistance to permethrin was high-intensity. Dose-response analysis regarding the susceptibility of larvae to temephos showed LC₅₀, LC_90, and LC₉₉ values of 0.013, 0.065, and 0.238 mg/l, respectively. These values indicate resistance when compared to the WHO diagnostic dose for temephos resistance of 0.012 mg/l.

Conclusion: The results of this study highlight the need for an urgent strategy to manage resistance to insecticides and strengthen the integrated management program of Ae. aegypti. This fact emphasizes the importance of reducing larval sources and promoting research on alternative methods and products.