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

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 re...

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Bibliographic Details
Main Authors: Gastón Mougabure Cueto, Eduardo Zerba, María Inés Picollo
Format: Article
Language:English
Published: Fundação Oswaldo Cruz (FIOCRUZ) 2006-05-01
Series:Memorias do Instituto Oswaldo Cruz
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Online Access:http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0074-02762006000300005
Description
Summary: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 (RH) on the laboratory rearing of Pediculus humanus capitis eggs was assessed. The optimal ranges for temperature and RH were 27-31°C and 45-75%. The susceptibility of human louse eggs to insecticide spinosad (a macrocyclic lactone) was assessed by immersion method. The results showed similar susceptibility to spinosad in early, medium, and late stages of head lice eggs. In addition, this study 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%).
ISSN:0074-0276
1678-8060