prevalence and susceptibility status of body louse (pediculus humanus humanus) (anoplura: pediculidae) to deltamethrin in urmia city, iran (2024)

Background: the body louse spreads diseases such as epidemic typhus and louse-borne relapsing fever and has shown resistance to various insecticides. while deltamethrin is used to treat infestations in some countries, research on its ef­fec­tiveness against body lice is limited. this study assessed the susceptibility of body lice to deltamethrin using a bioas­say.methods: body lice specimens were collected from an addiction treatment camp in urmia city, west azerbaijan prov­ince, iran. they were treated in 5 cm petri dishes lined with 1 ml of various concentrations of deltamethrin (0.01, 0.02, 0.04, 0.08, 0.16, 0.32, 0.64, 1.28, and 2.56 ppm) in acetone. thirty lice were tested per concentration, with mortality recorded after 24 hours. lethal concentrations of 50% and 90% (lc50 and lc90) were calculated using minitab and compared with spss. the regression line was plotted in excel 2013.results: a positive correlation was observed between the concentrations of deltamethrin and probit mortality in the regression analysis. the calculated lc50 and lc90 values for deltamethrin against body lice were 0.11 ppm and 2.15 ppm, respectively.conclusions: these findings suggest that the body lice population was susceptible to deltamethrin, suggesting its poten­tial as an alternative treatment, pending further clinical studies.