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Table 2 Knockdown time (kdT) for 50% and 95% of tested Anopheles gambiae s.l populations

From: Trends in DDT and pyrethroid resistance in Anopheles gambiaes.s. populations from urban and agro-industrial settings in southern Cameroon

Site Insecticide Period N kdT50 [CI95] (min) kdT95 [CI95] (min) RR Resistant status
Ipono 4%DDT Nov/2003 80 28.1 [22.4-31.9] 50.8 [45.0-62.7] 1.4 RC
  0.05%Deltamethrin   79 8.3 [5.4-10.9] 24.0 [18.1-38.9] 0.8 S
  0.75%Permethrin   79 11.5 [10.2-12.8] 44.3 [39.2-51.2] 1.3 S
  4%DDT Nov/2007 87 >60 >60 >3 R
  0.05%Deltamethrin   95 13.7 [12.7-14.7] 34.1 [31.3-37.4] 1.4 RC
  0.75%Permethrin   88 37.3 [34.1-40.6] >60 4.1 R
Nkolondom 4%DDT Nov/2003 80 >60 >60 >3 R
  0.05%Deltamethrin   89 12.2 [3.7-18.8] 42.8 [32.7-61.0] 1.2 S
  0.75%Permethrin   86 12.6 [9.6-15.4] 47.1 [37.3-67.4] 1.4 S
  4%DDT Nov/2007 84 >60 >60 >3 R
  0.05%Deltamethrin   89 20.1 [17.1-22.8] 45.8 [39. 1-58.4] 2.1 RC
  0.75%Permethrin   83 40.2 [37.6-42.8] >60 4.5 RC
Mangoum 4%DDT May/2003 80 >60 >60 >3 R
  0.05%Deltamethrin   84 24.1 [22.4-25.1] 39.2 [37.1-42.0] 2.5 R
  0.75%Permethrin   80 57.4 [52.3-68.0] >60 6.6 R
  4%DDT May/2007 91 >60 >60 >3 R
  0.05%Deltamethrin   84 19.4 [16.4-22.0] 48.3 [41.8-59.1] 2.0 RC
  0.75%Permethrin   106 54.2 [51.9-57.1] >60 6.1 R
Bonanloka 4%DDT May/2001 80 49.3 [41.8-58.7] >60 2.6 RC
  0.05%Deltamethrin   86 22.4 [21.2-23.7] 34.8 [31.2-39.0] 2.4 RC
  0.75%Permethrin   91 16.3 [14.9-17.7] 25.7 [22.4-29.6] 1.7 R
  4%DDT May/2005 80 51.6 [41.9-54.0] >60 2.7 R
  0.05%Deltamethrin   83 8.3 [7.6-9.1] 18.6 [16.8-21.1] 0.8 S
  0.75%Permethrin   85 6.2 [3.6-8.5] 23.8 [18.0-37.2] 0.7 S
  4%DDT May/2007 87 37.9 [36.5-39.5] >60 1.9 RC
  0.05%Deltamethrin   84 12.8 [10.6-14.6] 24.1 [20.4-31.6] 1.3 RC
  0.75%Permethrin   88 15.2 [13.2-17.1] 35.3 [30.7-42.6] 1.7 RC
  1. N: sample size; kdT50: knockdown time for 50% mosquitoes; kdT95: knockdown time for 95% mosquitoes; CI95: confidence interval at 95%; min: minutes; RR: resistance ratio (kdT50 of the tested population/kdT50of the Kisumu strain); S: susceptible; RC: resistance to be confirmed; R: resistant; Nov: November.