CDC’s "X-Ray Gun" Measures Insecticide on Nets

A CDC scientist has adapted an x-ray fluorescence analyzer to quickly measure the level of deltamethrin insecticide on insecticide-treated bed nets (ITNs). The insecticide in the net helps kill the mosquito that transmits malaria; it also reduces the number of mosquitoes that enter the house. This instrument can detect insecticide concentrations as little as 1 mg/m² (that is, about 1 teaspoon spread over 1.25 acres) and report results within one minute, without damaging the net or requiring chemical reagents. The analyzer is portable and has been used in ITN projects in Ethiopia, Laos, and Togo to measure how much insecticide has been lost from ITNs that people have slept under. Information about insecticide loss rates is vital to planning future ITN replacement campaigns.