Table 4.
Entomological outcomes by intervention (PBO LLIN vs no PBO LLIN, and IRS vs no IRS) in 2015 and 2016
|
Vector density per night per household |
Sporozoite rate |
EIR per month per household* | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| N | Mean (SD) | DR (95% CI) | p value | n/N (%) | OR (95% CI) | p value | N | Mean (SD) | DR (95% CI) | p value | |
| Year 1: 2015 | |||||||||||
| No PBO LLIN† | 896 | 2·61 (8·97) | 1 (ref) | .. | 20/952 (2%) | 1 (ref) | .. | 862 | 0·90 (5·42) | 1 (ref) | .. |
| PBO LLIN‡ | 961 | 1·85 (7·12) | 0·33 (0·16–0·69) | 0·0038 | 2/648 (<1%) | 0·25 (0·07–0·88) | 0·0317 | 911 | 0·13 (2·.07) | 0·13 (0·03–0·53) | 0·0055 |
| No IRS§ | 939 | 2·34 (8·18) | 1 (ref) | .. | 21/988 (2%) | 1 (ref) | .. | 901 | 1·01 (5·85) | 1 (ref) | .. |
| IRS¶ | 918 | 2·09 (7·96) | 0·63 (0·27–1·43) | 0·2652 | 1/612 (<1%) | 0·15 (0·02–1·02) | 0·0519 | 872 | 0·25 (0·89) | 0·03 (0·00–0·24) | 0·0014 |
| Interaction coefficient | .. | .. | 1·35 (0·44–4·18) | 0·5940 | .. | NA | NA | .. | .. | NA | NA |
| Year 2: 2016 | |||||||||||
| No PBO LLIN† | 1946 | 3·60 (16·86) | 1 (ref) | .. | 80/2236 (4%) | 1 (ref) | .. | 1793 | 1·15 (6·53) | 1 (ref) | .. |
| PBO LLIN‡ | 1953 | 2·68 (11·33) | 0·40 (0·20–0·80) | 0·0101 | 27/1931 (1%) | 0·38 (0·15–0·92) | 0·0331 | 1845 | 0·39 (3·91) | 0·33 (0·13–0·83) | 0·0189 |
| No IRS§ | 1942 | 2·82 (9·34) | 1 (ref) | .. | 64/2207 (3%) | 1 (ref) | .. | 1801 | 1·00 (6·04) | 1 (ref) | .. |
| IRS¶ | 1957 | 3·46 (18.01) | 0·93 (0·47–1·85) | 0·8309 | 43/1960 (2%) | 0·81 (0·37–1·78) | 0·5890 | 1837 | 0·58 (4·87) | 0·48 (0·25–0·94) | 0·0340 |
| Interaction coefficient | .. | .. | 1·00 (0·36–2·75) | 0·9970 | .. | 1·13 (0·35–3·63) | 0·8308 | .. | .. | 1·38 (0·47–4·08) | 0·5532 |
DR for vector density and EIR and OR for sporozoite rates are adjusted for their respective baseline value. EIR=entomological inoculation rate. DR=density ratio. OR=odds ratio. LLIN=long-lasting insecticidal net. PBO=piperonyl butoxide. IRS=indoor residual spraying. NA=not applicable.
The mean and DR of the EIR are weighted to account for the proportion of mosquitoes sampled to be tested for sporozoites. Interaction not estimated in year 1 for sporozoite and EIR outcomes, because sporozoite rate was null in the PBO LLIN plus IRS group.
Standard LLIN and standard LLIN plus IRS.
PBO LLIN and PBO LLIN plus IRS.
Standard LLIN and PBO LLIN.
Standard LLIN plus IRS and PBO LLIN plus IRS.