HEAD LICE-HOST INTERACTION: Human scalp extracts modifiy the behavior of Pediculus humanus capitis. Paola González-Audino, F. Galassi, A. Toloza, M. I. Picollo. Presentación Oral. . Foz de Iguazu, 4-7 Juli

GONZALEZ AUDINO P; M.I. PICOLLO; GALASSI, FEDERICO; I.ORTEGA-INSAURRALDE

Foz do Iguazu

Congreso; International Chemical Ecology Conference; 2016

Universidad Federal do Parana

P. h. capitis is acosmopolitan ectoparasite that affects the head of their human hosts. It ispresent in children of school age, in both developed and developing countries. It isbeen already stablished that P.h. capitisprefer to infest some individulas above others. However, no studies have gainedinsight into the reasons behind the existence of susceptible andnon-susceptible individuals. The main mechanism by which louse transmisionoccurs is the direct host to host contact. Behavioural assays were performed in order to study environmentalfactors that affect locomotor activity and to evaluate if human scalp extractsmodify the behaviour of head lice. Extracts were collected by rubbing filter paperonto scalp surface. Data were processed with video tracking system EthoVisionXT 10.1. VOCs present in the human scalp extracts were collected and analysedby  Solid Phase Microextraction-Gas Chromatography-MassSpectrometry (SPME-CG-MS).In a circular arena, headlice increase their locomotor activiy at 30 oCand dark conditions and are arrested by the extracts collected from human scalp.In olfactometer, head lice were significantly attracted to volatilesfrom the human source. The chemical composition of th extracts showed thepresence of hydrocarbons, alcohols, diols, saturated and unsaturated ketones, aldehydesand fatty and short chain acids. The role of these compounds alone and in mixturesis currently under study. These results represent the basis for the study ofchemical cues involved in human susceptibility to head lice.