Table 2.
Fluralaner dose-mortality assays, resistance ratios and deltamethrin diagnostic dose assays of five recently collected C. lectularius populations relative to an insecticide-susceptible (Harlan) population
| Population (abbreviation), year collected | Collection location (USA) | Fluralanera | Deltamethrin | ||||||
|---|---|---|---|---|---|---|---|---|---|
| n | LC50, ng/ml (95% CI)b | LC90, ng/ml (95% CI)b | Slope ± SEM | χ2 (df) | t-Ratioc | RR at LC50d (95% CI) | % mortality in HA at LD99 (n)e | ||
| Harlan (HA), 1973 (insecticide susceptible) | Fort Dix, NJ | 237 | 15.3 (11.7, 19.8) | 38.6 (28.3, 71.9) | 3.2 ± 0.4 | 7.9 (5) | 8.0* | N/A | N/A |
| Cincinnati (CIN), 2012 | Cincinnati, OH | 219 | 18.4 (16.2, 23.5) | 51.7 (41.4, 72.5) | 2.8 ± 0.3 | 3.5 (6) | 8.2* | 1.2 | 13 (45) |
| Fuller Mill (FM)f, 2017 | High Point, NC | 202 | 23.2 (13.8, 35.3) | 67.5 (42.5, 216.6) | 2.8 ± 0.3 | 12.6 (5) | 7.8* | 1.5* | 5 (40) |
| Winston Salem (WS), 2008 | Winston Salem, NC | 226 | 22.0 (15.3, 30.6) | 92.7 (58.4, 230.8) | 2.0 ± 0.3 | 8.0 (6) | 7.4* | 1.4* | 0 (48) |
| Shanda (SH), 2017 | Raleigh, NC | 220 | 21.1 (17.5, 25.4) | 65.0 (48.7, 102.0) | 2.6 ± 0.3 | 1.3 (5) | 7.7* | 1.4* | 0 (46) |
| Poultry House (PH), 2021 | Pennsylvania | 212 | 18.0 (15.3, 22.1) | 43.6 (34.7, 61.6) | 3.3 ± 0.4 | 4.9 (5) | 7.8* | 1.2 | 2 (50) |
| Ivermectina | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Harlan (HA), 1973 (insecticide susceptible) | Fort Dix, NJ | 231 | 61.0 (52.7, 69.9) | 114.9 (95.4, 154.7) | 4.7 ± 0.7 | 3.0 (4) | 6.4* | N/A | N/A |
Ivermectin dose-mortality assays are also shown for the Harlan (HA) population
N/A Not available, RR resistance ration
aOnly fully fed adult male bed bugs were included in these assays
bLC50 or LC90 of the bed bugs, estimated from probit analysis for each population. Values are in ng/ml of human blood
ct-Ratio of the slope. Values > 1.96 denote a significant regression at P < 0.05
dThe RR was calculated as LC50 of field-collected strain/LC50 of susceptible reference strain (HA). RR values with asterisk (*) were considered to be significant when their 95% CIs did not include 1.0 [31]
eThe LD99 dose of deltamethrin was estimated for the HA population from log dose–response probit analysis. This dose was used as a diagnostic dose and topically applied to field-collected bed bugs. Deltamethrin was diluted in acetone and 0.5 µl was applied to each insect. Percentage mortality at 2 days post administration and (n) are reported
fFuller Mill is the same strain referred to as Fuller Miller in González-Morales et al. [41]