In Vitro and In Vivo Evaluation of Infestation Deterrents Against Lice

Abstract

The human head louse is a cosmopolitan ectoparasite and frequently infests many people, particularly school-age children. Due to widespread pyrethroid resistance and the lack of efficient resistance management, there has been a considerable interest in the protection of uninfested people and prevention of reinfestation by disrupting lice transfer. In this study, two nonclinical model systems (in vitro and in vivo) were used to determine the efficacy of the infestation deterrents, Elimax lotion and Elimax shampoo, against human head lice or poultry chewing lice, respectively. With in vitro assessments, female head lice exhibited significantly higher avoidance responses to hair tufts treated with either of the test formulations, which led to significantly higher ovipositional avoidance when compared with female lice on control hair tufts. Additionally, both formulations were determined to be competent infestation deterrents in a competitive avoidance test in the presence of a known attractant (head louse feces extract). In in vivo assessments using a previously validated poultry model, Elimax shampoo was determined to be an efficacious deterrent against poultry chewing lice within Menopon spp. and Menacanthus spp.

Infections and pathology of free-roaming backyard chickens on St. Kitts, West Indies

“…External parasites, most likely Menopon spp. and Menacanthus spp., based on their location and previous studies 35 ( Supplementary Fig. 1A, 1B), were seen on 60 chickens (74%), although 5 chickens had feather loss.…”

Detection of the Nav channel kdr-like mutation and modeling of factors affecting survivorship of Culex quinquefasciatus mosquitoes from six areas of Harris County (Houston), Texas, after permethrin field-cage tests

“…In this study, no differences in the death odds-ratios were identified. All odds-ratios were combined to a single value and tested using the Cochran-Mantel-Haenszel (CMH) test statistic for comparing the odds of death for homozygous and heterozygous resistant genotypes [ 23 , 24 ]. The impact of the factors, area, genotype, distance and cage on the probability of survival of the mosquitoes was assessed through a logistic regression model.…”

Actualización y perspectiva integrada de la pediculosis

“…Los piojos, como cualquier forma de vida que evoluciona, desarrollan sofisticados mecanismos de resistencia contra los pediculicidas, los cuales heredan a las nuevas generaciones de insectos. Dicho fenómeno se agudiza por la falta de un manejo eficiente de estos medicamentos, razón por la cual en muchos países se están realizando estudios que confirman la creciente resistencia de P. capitis (55,56…”