impact of sub-lethal exposure to insecticides on vector control
DESCRIPTION
Impact of Sub-Lethal Exposure to Insecticides on Vector Control. Lee Cohnstaedt and Sandra Allan USDA-ARS-CMAVE Triservices Meeting Feburary 2010. Insecticide contact. Pyrethroids. If not dead, then what?. Mosquito species. Behavioral assays. Air+CO 2. Attractant. Entrance. - PowerPoint PPT PresentationTRANSCRIPT
Impact of Sub-Lethal Exposure to Insecticides on Vector Control
Lee Cohnstaedt and Sandra AllanUSDA-ARS-CMAVETriservices Meeting
Feburary 2010
Insecticide contact
Pyrethroids
If not dead, then what?
Mosquito species
Behavioral assays
Entrance
Air+CO2
*Capillary release attractant*CO2 release 50ml/min
Attractant
*Infrared light was used illuminate nocturnally active mosquitoes.
*Treatment level lethal dose25
Flight path analysis
Untreated Cx. quinquefasciatus
Deltamethrin treated Cx. quinquefasciatus
Flight path analysis
Untreated An. albimanus
Permethrin treated An. albimanus
Flight path analysis
Treated Ae. aegypti
Untreated Ae. aegypti
Average flight velocity
**Velocity
020406080
100120
Cx quinquefasciatus An albimanus Ae aegpyti
Mea
n ve
loci
ty (c
m/s
)
Contol Deltamethrin Permethrin
0
1
2
3
4
5
6
7
8
Cx quinquefasciatus An albimanus Ae aegypti
Seco
nds
Control Deltamethrin Permethrin
Time in flight
012345678
Cx quinquefasciatus An albimanus Ae aegypti
Seco
nds
Control Deltamethrin Permethrin
* *
Heading
-20-15-10
-505
101520
Deg
rees
Control Detamethrin Permethrin0
1
2
3
4
5
6
7
8
Cx quinquefasciatus An albimanus Ae aegypti
Seco
nds
Control Deltamethrin Permethrin
*
*
0.0%10.0%20.0%30.0%40.0%50.0%60.0%70.0%80.0%90.0%
100.0%
Cx quinquefaciatus An albimanus Ae aegypti
% B
lood
Fed
Control Permethrin Deltamethrin
Blood feeding
*
0
1
2
3
4
5
6
7
8
Cx quinquefasciatus An albimanus Ae aegypti
Seco
nds
Control Deltamethrin Permethrin
Implications
The sublethal affects of pyrethroids on a mosquito’s ability to detect and locate hosts may increase the efficacy of aerial and residual spraying treatments beyond their immediate killing impact.
Personal protective measures
Band
Sleeve
Phlebotomuspapatasi
Treatment Hand Band Sleeve Bite protection
Untreated 20 (29%) 11 (16%) 37 (54%) ---
Sleeve (permethrin) 43 (26%) 40 (24%) 84 (50%) -28.5%
Sleeve (permethrin) + Band (TL-I-73) 129 (27%) 86 (18%) 269 (56%) 16.9%
Band (TL-I-73) 39 (49%) 12 (15%) 28 (35%) 21.8%
Sleeve (permethrin) + Band (UB-21) 27 (40%) 12 (18%) 28 (41%) 94.1%
Number of landings per 20 minutesLanding site
Band
Sleeve
Implications
Sand flies predominantly land on the sleeve before moving towards the exposed skin; therefore a lethal insecticidal barrier at the uniform-skin interface will reduce disease transmission.
Acknowledgments• Uli Bernier• Matt Aubuchon
• Adrian Duehl• Erin Vrzal • Nathan Newlon