Lice resistance to pyrethroids found in half of US States

A recent study presented at the American Chemical Society has found that at least 25 US States have lice populations resistant to pyrethroids.

The study, presented during the 250th National Meeting and Exposition of the Americal Chemical Society, presented results of gene analysis of lice population samples from 30 US states. Twenty-five of those samples contained the kdr genetic mutations most commonly associated with pyrethroid resistance in insects.

This current study builds on previously published research from 2014 showing kdr-type mutations in 88% of North American head lice sampled.