Table 5.
Effect of intermittent preventive treatment on parasitaemia in the final community survey
| Number positive of total respondents | Prevalence | Crude risk ratio (95% CI) | p value | Adjusted risk ratio*(95% CI) | p value | ||
|---|---|---|---|---|---|---|---|
| Microscopy | |||||||
| All ages† | |||||||
| Control | 978 of 4467 | 23·1% | 1 | 1 | |||
| Intervention | 791 of 4455 | 19·0% | 0·82 (0·61–1·12) | 0·21 | 0·85 (0·73–1·00) | 0·05 | |
| <5 years | |||||||
| Control | 638 of 2705 | 23·6% | 1 | 1 | |||
| Intervention | 533 of 2702 | 19·7% | 0·84 (0·61–1·15) | 0·27 | 0·86 (0·73–1·02) | 0·09 | |
| 5–15 years | |||||||
| Control | 196 of 598 | 32·8% | 1 | 1 | |||
| Intervention | 150 of 603 | 24·9% | 0·76 (0·55–1·04) | 0·08 | 0·78 (0·60–1·00) | 0·05 | |
| >15 years | |||||||
| Control | 144 of 1164 | 12·4% | 1 | 1 | |||
| Intervention | 108 of 1150 | 9·4% | 0·76 (0·53–1·09) | 0·14 | 0·79 (0·59–1·05) | 0·11 | |
| Microscopy plus LAMP | |||||||
| All ages‡ | |||||||
| Control | 1419 of 2410 | 42·1% | 1 | 1 | |||
| Intervention | 1192 of 2312 | 37·5% | 0·89 (0·72–1·10) | 0·28 | 0·93 (0·84–1·04) | 0·18 | |
| <5 years | |||||||
| Control | 760 of 1156 | 40·4% | 1 | 1 | |||
| Intervention | 657 of 1077 | 37·1% | 0·92 (0·73–1·16) | 0·47 | 0·96 (0·84–1·09) | 0·50 | |
| 5–15 years | |||||||
| Control | 341 of 598 | 54·7% | 1 | 1 | |||
| Intervention | 281 of 603 | 43·8% | 0·80 (0·67–0·96) | 0·02 | 0·84 (0·73–0·97) | 0·02 | |
| >15 years | |||||||
| Control | 318 of 656 | 42·7% | 1 | 1 | |||
| Intervention | 254 of 632 | 34·6% | 0·81 (0·64–1·02) | 0·07 | 0·85 (0·73–1·00) | 0·06 | |
| Prevalence of gametocytaemia | |||||||
| Control | 217 of 4467 | 5·3% | 1 | 1 | |||
| Intervention | 207 of 4455 | 5·1% | 0·95 (0·64–1·40) | 0·78 | 1·00 (0·73–1·37) | 0·99 | |
| Prevalence of anaemia§ | |||||||
| Control | 1083 of 2705 | 40·0% | 1 | 1 | |||
| Intervention | 1040 of 2702 | 38·5% | 0·96 (0·80–1·15) | 0·67 | 1·03 (0·87–1·23) | 0·72 | |
LAMP=loop-mediated isothermal amplification.
Adjusted for baseline community parasite prevalence (0–13%, >13–25%, >25–33%, or >33%), sex, individual bednet use, school type, subcounty, and socioeconomic status quintiles, eaves status (all closed, some closed, or all open), window screening status (all, some, or none screened), and latitude (<4°, 4 to <5°, or >5°).
Overall prevalence was weighted by the inverse of the percentage of people counted in each age group in the cluster census (17·3% for <5 years, 33·1% for 5–15 years, and 49·6% for >15 years).
Overall prevalence weighted by the inverse of the percentage of the population (17·3% of children <5 years, 33·1% of children aged 5–15 years, and 49·6% of people >15 years) multiplied by the probability of being sampled for LAMP (the product of the percentage negative by microscopy, because only negative samples were eligible for LAMP testing) and an age-related probability. Sampling was done in 25% of from children <5 years, 100% of children aged 5–15 years, and 50% of people >15 years.
Only measured in children <5 years and was defined as haemoglobin concentration <110 g/L.