Acute toxicities of deltamethrin and β-cyfluthrin to Richmond and Harlan strain bed bugs^a.

aInsecticide toxicities are presented as LD50 and their 95% confidence intervals (95% CI) in nanograms (ng) per insect, the dose at which 50% of the test populations were killed in a 24-h bioassay. bResistance ratios (RR) were calculated by RR = LD50Richmond/LD50 Harlan. The asterisk next to the ratios indicates a significant difference between the LD50 values for the Richmond and Harlan strains based on the non-overlapping 95% CI of the LD50 values.