UNIDEF   23986
UNIDAD DE INVESTIGACION Y DESARROLLO ESTRATEGICO PARA LA DEFENSA
Unidad Ejecutora - UE
artículos
Título:
First Determination of Pyrethroid Knockdown Resistance Alleles in Human Head Lice (Phthiraptera: Pediculidae) From Chile
Autor/es:
DRESSEL ROA, PAULINA; DEL SOLAR KUPFER, CARMEN PAZ; ROCA-ACEVEDO, GONZALO; TOLOZA, ARIEL CEFERINO
Revista:
JOURNAL OF MEDICAL ENTOMOLOGY
Editorial:
ENTOMOLOGICAL SOC AMER
Referencias:
Lugar: Lanham; Año: 2019
ISSN:
0022-2585
Resumen:
The infestation with the human ectoparasite, Pediculus humanus capitis (De Geer), is a common public healthproblem affecting schoolchildren worldwide. In Chile, the main active ingredients present in the over-thecounterpediculicides contain pyrethroids. Despite the extended use of these products, there is no evidenceof the insecticide resistance status of the head lice geographically located in Chile. The most extended resistantmechanism of pyrethroids consists of the target site insensitivity (Kdr) determined by the presence ofmutations linked to insecticide-binding sites in the voltage-sensitive sodium channel. T917I is recognized as themain mutation in head lice, and detection is considered to be a biomarker of resistance. The goal of the presentstudy was to detect the presence and distribution of T917I mutation in five geographic locations of Chile. All fivegeographically selected louse populations had a frequency of pyrethroid resistance genes that ranged from36 to 77%, and 94.9% of the collected head lice had one or two T917I mutant alleles. Moreover, the frequencyof the aggregate resistant alleles was 50.5%. This is the first evidence that head lice in Chile had the mutationscommonly associated with the resistance to pyrethroids. Moreover, the overrepresentation of heterozygotes inthe studied populations suggests that head lice in Chile are currently under active selective pressure.