Efficacy of Various Insecticides Against Bed Bugs Dr. Bill Donahue Sumiko De La Vega Nebraska Urban Pest Management Conference February 12-13, 2013 “Brood Centers” • Bed bugs are thigmotactic preferring rough surfaces such as wood or paper. • Cluster together in contact with each other where fecal matter, egg shells and exuvia accumulate - Semiochemicals • Return to these harborages after a blood meal. • Quiescent state while digestion takes place. • Stimulus to leave harborage? Hunger? “Brood Centers” Repellent A chemical that makes unattractive to arthropods a habitat, food source, or oviposition site ordinarily sought and frequented. “Push-Pull” Theory – Repel and Attract - used in the same environment Objective To evaluate the contact activity (mortality, repellency, egg distribution and hatch) of selected strains of bed bugs exposed to treated fabric substrates. Chemicals Evaluated • • • • • Permethrin Impregnated Fabrics (3) – 0.52% a.i. Phantom Aerosol – Chlorfenapyr 0.5% Alpine Aerosol – Dinotefuran 0.5% Bedlam Aerosol – Sumithrin 0.4%, MGK-264 1.6% Bed Bug Gel - Lactic Acid 20%, Rosemary Oil 1%, Hops Flower Essential Oil 1% Bed Bug Strains • “Harlan” – Laboratory Susceptible Strain (Ft. Dix, NJ 1973 - SRL 2008) Adults Mixed Sex Ratio • “Earl” – SRL Field Collected (Modesto, CA - 2007) Susceptible Strain – Adults Mixed Sex Ratio • “James” – SRL Field Collected (Modesto, CA - 2009) Strain, 7X Permethrin Resistant – Adults Mixed Sex Ratio Test System * Forced Exposure non-choice test Permethrin Fabric “Choice Test” Aerosol “Choice Test” Average percent mortality of adult bed bugs (2 Strains) confined to three types of permethrin treated fabrics (“NonChoice”) compared with an untreated control as a continuous forced exposure lethal time (LT) evaluation Fabric Type 1 hr Harlan 1 hr James 2 hr Harlan 2 hr James 4 hr Harlan 4 hr James 24 hr Harlan 24 hr James #1 Beige UPH 4 0 26 12 58 24 100 54 #2 Black Stitch 16 0 22 6 64 18 100 50 #3 Knit Ticking 44 10 56 48 94 66 100 78 #4 UTC Woven 0 0 0 0 0 0 0 0 Average percent mortality of adult bed bugs (Harlan) confined to three types of permethrin treated fabrics (“Choice Test”) compared with an untreated control as a continuous exposure lethal time (LT) evaluation Fabric Type 4 hr 24 hr 48 hr 72 hr 96 hr #1 Beige UPH 14 64 72 76 76 #2 Black Stitch 26 46 64 72 78 #3 Knit Ticking 30 52 60 66 68 #4 UTC Woven 0 0 0 0 0 Total # of Eggs, average percent hatch and average percent nymph mortality of bed bugs (Harlan) confined to three types of permethrin treated fabrics (“Choice Test”) compared with an untreated control as a continuous exposure evaluation Treated Side Total # Eggs Untreated Side Total # Eggs Avg.% Hatch Avg. % Nymph Mortality #1 Beige UPH 3 73 83.5 19.7 #2 Black Stitch 6 90 86.6 34.4 #3 Knit Ticking 2 124 69.8 19.8 #4 UTC Woven 124 189 87.0 2.6 Fabric Type Mortality, distribution, average percent hatch and average percent nymph mortality of bed bugs (Harlan) confined to treated mattress ticking (“Choice Test”) compared with an untreated control as a continuous exposure evaluation Treatment Max. Adult % Mort 96 hr % Adults Untreated Side Avg % Distribution Eggs 4 hr 96 hr Treated Untreated Avg % Hatch Avg % Nymph Mortality Chlorfenapyr Aerosol 0 96 82 13 87 96.6 78.0 Dinotefuran Aerosol 0 58 74 31 69 98.0 0.6 Sumithrin Aerosol 42 68 64 1 99 97.1 41.7 Lactic Acid + Essential Oils 0 96 100 0 100 100 0.6 Conclusions • Reliable and predictive small scale bioassay • Sensitive – bed bug strains, chemicals (actives & formulations) • Demonstrates repellency – adults/nymphs, oviposition sites – “Push-Pull” applications, but need to understand the dynamics when including the host and harborage in human habitats • Evaluate control options based on unique bed bug behavior – “Brood Centers” - Urban IPM Questions?