LSTM Home > LSTM Research > LSTM Online Archive

Overcoming insecticide resistance in Anopheles mosquitoes by using faster-acting solid forms of deltamethrin

Carson, Jessica, Erriah, Bryan, Herodotou, Stephanie, Shtukenberg, Alexander, Smith, Leilani, Ryazanskaya, Svetlana, Ward, Michael, Kahr, Bart and Lees, Rosemary ORCID: (2023) 'Overcoming insecticide resistance in Anopheles mosquitoes by using faster-acting solid forms of deltamethrin'. Malaria Journal, Vol 22, Issue 1, e129.

12936_2023_Article_4554.pdf - Published Version
Available under License Creative Commons Attribution.

Download (2MB) | Preview


Controlling malaria-transmitting Anopheles mosquitoes with pyrethroid insecticides is becoming increasingly challenging because of widespread resistance amongst vector populations. The development of new insecticides and insecticidal formulations is time consuming and costly, however. A more active crystalline form of deltamethrin, prepared by heating the commercial crystalline form, previously was reported to be 12-times faster acting against susceptible North American Anopheles quadrimaculatus mosquitoes. Herein the potential for heat-activated deltamethrin dispersed on chalk to overcome various resistance mechanisms amongst five West African Anopheles strains is investigated, and its long-term sustained lethality evaluated.

The more active deltamethrin form was generated in a commercial dust containing deltamethrin by heating the material as purchased. Tarsal contact bioassays were conducted to investigate its efficacy, potency, and speed of action against resistant Anopheles populations compared to the commercially available form of deltamethrin dust.

In all cases, D-Fense Dust heated to generate the more active form of deltamethrin was substantially more effective than the commercially available formulation. 100% of both Banfora M and Kisumu populations were knocked down 10 min post-exposure with no recovery afterwards. Gaoua-ara and Tiefora strains exhibited 100% knockdown within 15 min, and the VK7 2014 strain exhibited 100% knockdown within 20 min. In all cases, 100% mortality was observed 24 h post-exposure. Conversely, the commercial formulation (unheated) resulted in less than 4% mortality amongst VK7 2014, Banfora, and Gaoua-ara populations by 24 h, and Tiefora and Kisumu mosquitoes experienced 14 and 47% mortality by 24 h, respectively. The heat-activated dust maintained comparable efficacy 13 months after heating.

The heat-activated form of commercial deltamethrin D-Fense Dust outperformed the material as purchased, dramatically increasing efficacy against all tested pyrethroid-resistant strains. This increase in lethality was retained for 13 months of storage under ambient conditions in the laboratory. Higher energy forms of commonly used insecticides may be employed to overcome various resistance mechanisms seen in African Anopheles mosquitoes through more rapid uptake of insecticide molecules from their respective solid surfaces. That is, resistant mosquitoes can be killed with an insecticide to which they are resistant without altering the molecular composition of the insecticide.

Item Type: Article
Subjects: QX Parasitology > Insects. Other Parasites > QX 510 Mosquitoes
QX Parasitology > Insects. Other Parasites > QX 515 Anopheles
Faculty: Department: Biological Sciences > Vector Biology Department
Digital Object Identifer (DOI):
SWORD Depositor: JISC Pubrouter
Depositing User: JISC Pubrouter
Date Deposited: 25 Apr 2023 09:28
Last Modified: 25 Apr 2023 09:28


View details

Actions (login required)

Edit Item Edit Item