Background
Methods
Description of study sites
Mosquito collection
Insecticide susceptibility tests
Extraction and preparation of LLINs sub-samples
WHO cone bioassay
Chemical analysis for insecticide contents
Statistical data analysis
Ethical considerations
Results
Vector populations
Insecticide susceptibility
Insecticide | Mosquito tested | KDT50 (± 95 % CI) | KDT95 (± 95 % CI) | Mortality rate |
---|---|---|---|---|
Deltamethrin (0.05 %) | 100 | 52.81 (47.11–58.51) | 203.07 (127.33–278.81) | 85 |
Permethrin (0.75 %) | 100 | 31.33 (29.28–33.38) | 77.08 (65.88–88.29) | 97 |
Bendiocarb (0.1 %) | 100 | 32.42 (30.78–34.06) | 58.84 (53.18–64.50) | 92 |
Propoxur (0.1 %) | 100 | 29.37 (27.17–31.58) | 85.92 (70.97–100.88) | 94 |
Insecticide | Mosquito tested | KDT50 (95 % CI) | KDT95 (95 % CI) | Mortality rate |
---|---|---|---|---|
Deltamethrin (0.05 %) | 125 | 31.61 (29.81–33.41) | 75.24 (65.82–84.65) | 99.2 |
Permethrin (0.75 %) | 100 | 32.26 (30.25–34.27) | 75.11 (64.80–85.42) | 97 |
Bendiocarb (0.1 %) | 100 | 33.28 (31.55–35.01) | 62.29 (56.32–68.26) | 99 |
Propoxur (0.1 %) | 100 | 34.9 (33.24–36.61) | 62.29 (56.33–68.26) | 98 |
DDT (4 %) | 100 | 42.6 (40.51–44.69) | 81.59 (71.40–91.77) | 97 |
Bio-efficacy of LLINs against wild-caught vector populations
LLINs | Mosquito tested per site | Bio-efficacy indexes | Study districts | ||
---|---|---|---|---|---|
Balama (A. funestus) | Mocuba (A. funestus) | Milange (A. gambiae) | |||
Olyset | 360 | KD 60 (±se) |
35.55 (±3.15)
|
49.14 (±2.47)
|
57.5 (±2.71)
|
Mortality rate (±se) |
20.9 (±2.34)
|
38.07 (±3.07)
|
40.77 (±2.82)
| ||
Permanet 2.0 | 360 | KD 60 (±se) | 69.72 (±3.40) | 78.61 (±2.18) | 91.25 (±1.30) |
Mortality rate (±se) | 60.48 (±3.64) | 81.94 (±2.32) | 89.65 (±1.65) | ||
Permanet 3.0 | 600 | KD 60 (±se) | 93.33 (±1.12) | 85.16 (±1.43) | 99.64 (±0.36) |
Mortality rate (±se) | 85.5 (±2.09) | 90.16 (±1.27) | 98.92 (±0.61) | ||
NetProtect | 360 | KD 60 (±se) |
61.38 (±2.79)
| 62.22 (±2.52) | 83.88 (±1.61) |
Mortality rate (±se) |
23.95 (±2.34)
| 63.61 (±2.95) | 78.87 (±3.56) | ||
Interceptor | 360 | KD 60 (±se) | – | – | 80.83 (±1.87) |
Mortality rate (±se) | – | – | 77.84 (±2.16) |
Permanet 3.0 sides | Mosquito tested per site | Bio-efficacy indexes | Study sites | ||
---|---|---|---|---|---|
Balama (A. funestus) | Mocuba (A. funestus) | Milange (A. gambiae) | |||
Lower side (border) | 240 | KD 60 (±se) |
90 (±2.06)
| 84.58 (±1.91) | 100 (±0.00) |
Mortality rate (±se) |
81.46 (±3.69)
| 87.29 (±2.10) | 98.33 (±1.15) | ||
Upper side | 240 | KD 60 (±se) |
93.33 (±1.92)
| 80 (±2.60) | 99 (±1) |
Mortality rate (±se) |
82.29 (±3.35)
| 88.54 (±2.13) | 99 (±1) | ||
Roof | 120 | KD 60 (±se) | 100 (±0.00) | 96.67 (±1.55) | 100 (±0.00) |
Mortality rate (±se) | 100 (±0.00) | 99.17 (±0.83) | 100 (±0.00) |
Bio-efficacy against colony susceptible vectors
Type of LLIN | Mosquito tested | KD 60 ± se | Mortality rate ± se |
---|---|---|---|
Olyset | 360 | 68.33 ± 2.26 | 90.36 ± 1.35 |
Permanet 2.0 | 360 | 94.72 ± 1.12 | 100 ± 0.00 |
Permanet 3.0 | 600 | 98.17 ± 0.58 | 100 ± 0.00 |
NetProtect | 360 | 83.89 ± 1.80 | 99.44 ± 0.39 |
Interceptor | 360 | 80.56 ± 1.63 | 98.84 ± 0.57 |
Insecticide contents on the LLINs
Net type | Active ingredient | Net section | Target mean dose | Target dose range | Measured mean dose | Measured dose within product target range? |
---|---|---|---|---|---|---|
Interceptor (IT) | Alpha-cypermethrin | Roof | 200 mg/m2
| 150.0–250.0 | 204.2 mg/m2
| Yes |
Alpha-cypermethrin | Sides | 200 mg/m2
| 150.0–250.0 | 204.2 mg/m2
| Yes | |
NetProtect (NP) | Deltamethrin | Roof | 1.8 g/kg | 1.35–2.25 | 1.0 g/kg | Under |
Deltamethrin | Sides | 1.8 g/kg | 1.35–2.25 | 1.0 g/kg | Under | |
Olyset (OL) | Permethrin | Roof | 20 g/kg | 17.0–23.0 | 23.2 g/kg | Over |
Permethrin | Sides | 20 g/kg | 17.0–23.0 | 23.6 g/kg | Over | |
Permanet 2.0 (PN2) | Deltamethrin | Roof | 55 mg/m2
| 41.25–68.75 | 73.2 mg/m2
| Over |
Deltamethrin | Sides | 55 mg/m2
| 41.25–68.75 | 65.8 mg/m2
| Yes | |
Permanet 3.0 (PN3) | Deltamethrin | Roof | 4 g/kg | 3.0–5.0 | 3.4 g/kg | Yes |
Deltamethrin | Lower side (border) | 2.8 g/kg | 2.1–3.5 | 3.0 g/kg | Yes | |
Deltamethrin | Upper side | 2.8 g/kg | 2.1–3.5 | 3.1 g/kg | Yes | |
PBO | Roof | 25 g/kg | 18.75–31.25 | 28.8 g/kg | Yes |