Preventive termite treatment
Introduction
Cypermethrin is a non-systemic and non-volatile insecticide that acts by contact and ingestion.[4] It offers effective insect control, with no activity on mites and low toxicity for mammals. It has very good effectiveness in lepidopterans, coleopterans and hemipterans. Cypermethrin is also used to control flies and other insects in the habitats of domestic animals and pests that affect public health (mosquitoes and cockroaches).
It was developed by Michael Elliott's group (Rothamsted Research)[5] and is a type II pyrethroid.
Mode of action
Cypermethrin is a broad-spectrum pyrethroid insecticide. It was synthesized in 1974 and was first marketed in 1977 as a highly active synthetic pyrethroid.[6].
It is considered an effective insecticide against a wide range of pests in agriculture, public health and livestock. In agriculture, its main use is against foliage pests and certain pests in superficial soils, such as worms, but due to its rapid decomposition, its use against pests below the soil surface is not recommended.[6].
Cypermethrin acts on voltage-gated sodium channels located in the axons of neurons. This results in overexcitation of the central nervous system (CNS) and peripheral nervous system (PNS). There is a direct toxic action, and an indirect repellent action.
Insects absorb cypermethrin on the body surface, so it spreads throughout the insect's body. This pyrethroid causes sodium channels in nerve cells to no longer close. Na+ ions flow freely inside the cell and uncontrollable nerve impulses are produced.
This leads first to states of excitement with convulsions, then to coordination problems and finally to paralysis. The insect remains immobile within a few minutes, called the "knockdown effect." The repellent effect is based on an irritation of the tactile elements on the extremities ("foot retraction effect") of the arthropods.
A primary excitation of the PNS originates in the insect, which causes the insect to flap its limbs and wings, moving away from the treatment site (flushing-out). It is then absorbed through the chitinous exoskeleton of arthropods, thereby stimulating the central nervous system. Once the insecticide enters the insect's body, it causes paralysis of the CNS (residence period) and the insect becomes paralyzed. Unable to feed for more than 120 hours, he dies from starvation. The death of the insect only occurs after some time. Ticks die within two days. The effect of cypermethrin lasts from 2 weeks to 5 months.