This test measures the behavioural response of arthropods to different repellents in a controlled environment, aiding in the development and optimization of effective formulations.
The olfactometer consists of a choice chamber where arthropods are exposed to two or more odour sources, one being the repellent/attractant being tested and the other being a control. The arthropods' movement and preference for the scents are observed and recorded, providing insights into the product’s activity.
Blood feeding assays with Hemotek
Blood feeding assays using the Hemotek membrane feeding system represent a valuable method in the evaluation of the repellence offered by some products.
This device provides a food source to blood-sucking insects through a thermoregulated artificial membrane containing blood. In repellent testing, the treated substrate is placed on the Hemotek device, so that the response of the insects to the product is observed, evaluating their intention to bite (landing) or their feeding (feeding).
Arm-in-cage test
This test is designed for the evaluation of topical repellents against mosquitoes. It consists of introducing the volunteers' arm into a cage with a certain number of insects.
Thereby, mosquito landing and/or biting activity can be assessed by comparison between an arm previously treated with the product and a control arm where no repellent is applied.
A variant of this assay is the "arm-to-cage" test, in which the arm is placed next to the cage instead of inside it.
Room test: topical and spatial repellents
In this test, volunteers treated with the repellent are exposed to mosquitoes released into an enclosed space, room or chamber. The test can also be carried out with spatial repellents, allowing the product to be tested to act when exposing volunteers to the released insects.
A known number of arthropods, typically mosquitoes, is inserted into the room record to observe their activity when landing and biting volunteers.
Thereby, this test allows to evaluate the protection effectiveness of the repellent in a situation closer to reality.
