Table 4 Susceptibility of Ae. aegypti adults to different insecticides at diagnostic dose (LC ₉₉ × 2) and insecticides with synergists from various locations in Singapore

Total exposed (n)

1261

1239

1331

1175

1126

1184

1198

1208

Cypermethrin only

100 ± 0

1.27 ± 1.27

58.93 ± 8.92

29.50 ± 8.18

34.63 ± 6.03

15.20 ± 2.80

27.53 ± 1.61

68.44 ± 2.55

Cypermethrin + PBO

100 ± 0

1.62 ± 0.36

14.60 ± 5.06*

8.43 ± 2.09

11.60 ± 5.40*

5.41 ± 1.46*

33.83 ± 2.65

32.09 ± 6.15*

Cypermethrin + DEF

100 ± 0

11.03 ± 1.70*

12.67 ± 2.08*

37.19 ± 3.08

27.34 ± 5.77

29.87 ± 3.29*

53.79 ± 4.61*

29.63 ± 9.90*

Cypermethrin + TPP

100 ± 0

0.40 ± 0.40

3.50 ± 0.60*

2.42 ± 0.03*

0.83 ± 0.83*

2.14 ± 0.88*

16.79 ± 7.40

6.13 ± 3.97*

Cypermethrin + 3 synergists

4.54 ± 1.64

8.25 ± 0.94*

13.64 ± 6.30

15.47 ± 6.24

2.93 ± 0.43*

31.51 ± 3.75

35.29 ± 10.56*

Total exposed (n)

1250

1228

1182

1239

1252

1224

1219

1206

Permethrin only

100 ± 0

5.75 ± 0.98

11.59 ± 2.93

16.58 ± 4.22

18.57 ± 3.44

27.39 ± 6.83

6.00 ± 1.32

33.88 ± 7.72

Permethrin + PBO

100 ± 0

3.29 ± 2.21

15.99 ± 6.56

22.45 ± 5.52

14.87 ± 0.61

15.14 ± 1.96

3.94 ± 1.97

7.24 ± 2.51*

Permethrin + DEF

100 ± 0

27.35 ± 5.03*

17.59 ± 3.25

29.21 ± 4.47

16.51 ± 1.97

39.95 ± 14.67

25.61 ± 3.23*

38.47 ± 6.85

Permethrin + TPP

100 ± 0

1.22 ± 0.70*

1.60 ± 1.06*

1.21 ± 0.70*

0.78 ± 0.39*

3.16 ± 1.36*

1.20 ± 0.70*

2.02 ± 0.39*

Permethrin + 3 synergists

100 ± 0

1.62 ± 0.81*

1.21 ± 0.70*

1.19 ± 1.19*

1.16 ± 0.01*

6.43 ± 3.21*

0.42 ± 0.42*

14.77 ± 3.67

Total exposed (n)

1240

1193

1245

1215

1235

1185

1265

1144

Etofenprox only

100 ± 0

12.96 ± 6.68

21.87 ± 18.96

26.04 ± 19.23

16.47 ± 11.66

28.86 ± 6.95

14.40 ± 10.79

14.94 ± 13.05

Etofenprox + PBO

100 ± 0

27.16 ± 8.50

23.90 ± 12.29

47.43 ± 9.19

20.71 ± 3.78

38.67 ± 12.55

22.32 ± 2.21

41.68 ± 11.48

Etofenprox + DEF

100 ± 0

31.58 ± 9.25

27.82 ± 11.22

55.49 ± 0.53

41.83 ± 5.03

38.64 ± 9.94

32.35 ± 3.95

56.09 ± 6.46*

Etofenprox + TPP

100 ± 0

7.07 ± 2.28

1.54 ± 1.01

2.08 ± 2.08

2.06 ± 0.43*

3.91 ± 1.04*

4.39 ± 1.42

6.10 ± 3.47

Etofenprox + 3 synergists

100 ± 0

12.15 ± 5.96

19.07 ± 10.92

18.84 ± 1.88

13.62 ± 5.09

15.01 ± 3.93

7.40 ± 1.41

20.71 ± 2.24

Total exposed (n)

1248

1290

1154

1089

1242

1256

1256

1177

Pirimiphos-methyl only

100 ± 0

100 ± 0

100 ± 0

99.25 ± 0.75

100 ± 0

95.98 ± 4.02

100 ± 0

98.41 ± 1.59

Pirimiphos-methyl + PBO

100 ± 0

95.40 ± 4.04

79.82 ± 10.09*

47.55 ± 5.16*

95.78 ± 3.15

88.12 ± 8.37

98.86 ± 1.14

81.79 ± 10.03

Pirimiphos-methyl + DEF

100 ± 0

98.85 ± 0.66

98.80 ± 0.72

93.46 ± 5.95

97.00 ± 1.91

99.58 ± 0.42

99.59 ± 0.41

100 ± 0

Pirimiphos-methyl + TPP

100 ± 0

81.36 ± 7.52*

60.16 ± 11.86*

66.01 ± 10.99*

97.27 ± 1.71

2.27 ± 2.27*

67.96 ± 5.78*

64.92 ± 16.35

Pirimiphos-methyl + 3 synergists

100 ± 0

100 ± 0

55.95 ± 10.72*

2.75 ± 1.41*

2.43 ± 1.90*

50.34 ± 5.44*

8.75 ± 2.43*

28.12 ± 3.94*