Embryonic development of human lice: rearing conditions and susceptibility to spinosad

MOUGABURE CUETO G., E. ZERBA & M. I. PICOLLO

MEMóRIAS DO INSTITUTO OSWALDO CRUZ.

Instituto Oswaldo Cruz

Lugar: Río de Janeiro; Año: 2006 vol. 101 p. 257 - 261

0074-0276

The embryonic development of human lice was evaluated according to the changes in the morphology of the embryo observed through the transparent chorion. Based on ocular and appendage development, three stages of embryogenesis were established: early, medium, and late. Influence of temperature and relative humidity on the laboratory rearing of Pediculus humanus capitis eggs was assessed. The optimal range for temperature and relative humidity were 27-31°C and 45-75% RH. The susceptibility of human lice eggs to spinosad was assessed by immersion method. The results showed similar susceptibility of head and body lice eggs to spinosad, an insecticide that has not been used as pediculicide in Argentina (lethal concentration 50% = 0.01%). Key words: human lice - embryogenesis - spinosad