Volume 13, Number 2—February 2007
Research
Reduced Efficacy of Insecticide-treated Nets and Indoor Residual Spraying for Malaria Control in Pyrethroid Resistance Area, Benin
Raphael N’Guessan*, Vincent Corbel†, Martin Akogbéto‡§, and Mark Rowland
Table 1
Residual activity of lambdacyalothrin (insecticide)-treated nets (ITNs) and indoor residual spraying over 3 mo in experimental huts, Malanville and Ladji field stations*
| When and where substrate tested | ITNs at 18 mg/m2 | Indoor residual spraying at 30 mg/m2 | ||||
|---|---|---|---|---|---|---|
| Sides + top of net | Ceiling | Walls | ||||
| No. tested | % Corrected mortality | No. tested | % Corrected mortality | No. tested | % Corrected mortality | |
| Wk 0 | ||||||
| Malanville | 77 | 100 | 33 | 100 | 60 | 100 |
| Ladji | 51 | 100 | 30 | 93.3 | 54 | 100 |
| Wk 2 | ||||||
| Ladji | 52 | 100 | 22 | 100 | 41 | 100 |
| Wk 4 | ||||||
| Ladji | 54 | 100 | 21 | 52.4 | 47 | 42.5 |
| Wk 6 | ||||||
| Ladji | 57 | 100 | 25 | 80.0 | 45 | 31.1 |
| Wk 8 | ||||||
| Malanville | 52 | 100 | 29 | 41.4 | 54 | 2.6 |
| Ladji | 44 | 97.7 | 8 | 25.0 | 39 | 18.5 |
*As determined by using World Health Organization cone bioassays and susceptible Anopheles gambiae (Kisumu).
