Table 4.
Household risk factors for clinical malaria in children aged 6 months to 10 years in Nagongera, Uganda, before and after the introduction of indoor residual spraying
|
Before indoor residual spraying (Aug 19, 2011, to Jan 31, 2015) |
After indoor residual spraying (Feb 1, 2015, to June 30, 2017) |
||||||
|---|---|---|---|---|---|---|---|
| Malaria incidence* (total person years) | IRR (95% CI)† | p value | Malaria incidence* (total person years) | IRR (95% CI)† | p value | ||
| Age | |||||||
| 6 months to <2 years | 4·71 (7·2) | 1 (ref) | ·· | 0·43 (14·0) | 1 (ref) | ·· | |
| 2 to <5 years | 4·18 (257·2) | 0·87 (0·74–1·03) | 0·10 | 0·56 (246·7) | 1·37 (0·60–3·10) | 0·46 | |
| 5 to 10 years | 2·43 (620·3) | 0·48 (0·40–0·58) | <0·0001 | 0·54 (267·1) | 1·62 (0·72–3·68) | 0·25 | |
| Sex | |||||||
| Female | 2·73 (398·8) | 1 (ref) | ·· | 0·52 (250·4) | 1 (ref) | ·· | |
| Male | 3·14 (486·0) | 1·14 (0·99–1·31) | 0·07 | 0·57 (277·4) | 1·10 (0·81–1·49) | 0·54 | |
| 2013 household data | |||||||
| Wealth index tertile | |||||||
| Poorest | 2·94 (286·9) | 1 (ref) | ·· | 0·72 (185·2) | 1 (ref) | ·· | |
| Middle | 3·05 (309·4) | 1·10 (0·89–1·36) | 0·38 | 0·50 (190·7) | 0·70 (0·51–0·95) | 0·02 | |
| Least poor | 2·88 (265·3) | 1·05 (0·83–1·32) | 0·70 | 0·40 (151·8) | 0·55 (0·39–0·78) | 0·001 | |
| Main roof material | |||||||
| Thatched | 3·24 (347·4) | 1 (ref) | ·· | 0·58 (231·3) | 1 (ref) | ·· | |
| Tiles or metal | 2·77 (537·3) | 0·94 (0·76–1·16) | 0·56 | 0·53 (296·5) | 1·10 (0·85–1·42) | 0·47 | |
| Main wall material | |||||||
| Mud | 3·02 (736·2) | 1 (ref) | ·· | 0·56 (452·1) | 1 (ref) | ·· | |
| Cement, wood, or metal | 2·67 (148·5) | 0·93 (0·66–1·30) | 0·66 | 0·49 (75·7) | 1·20 (0·84–1·71) | 0·33 | |
| Eaves | |||||||
| Open | 3·11 (433·9) | 1 (ref) | ·· | 0·58 (277·1) | 1 (ref) | ·· | |
| Closed | 2·81 (450·8) | 0·95 (0·78–1·15) | 0·58 | 0·51 (250·7) | 1·01 (0·78–1·31) | 0·95 | |
| 2016 household data | |||||||
| Wealth index tertile | |||||||
| Poorest | 3·19 (264·4) | 1 (ref) | ·· | 0·65 (191·3) | 1 (ref) | ·· | |
| Middle | 2·98 (294·3) | 0·97 (0·76–1·23) | 0·79 | 0·59 (176·7) | 0·92 (0·66–1·27) | 0·61 | |
| Least poor | 3·07 (234·1) | 0·99 (0·77–1·27) | 0·93 | 0·38 (154·5) | 0·58 (0·42–0·82) | 0·002 | |
| Main roof material | |||||||
| Thatched | 2·97 (212·9) | 1 (ref) | ·· | 0·55 (149·9) | 1 (ref) | ·· | |
| Tiles or metal | 3·11 (579·8) | 1·16 (0·92–1·46) | 0·22 | 0·55 (372·7) | 1·09 (0·80–1·49) | 0·59 | |
| Main wall material | |||||||
| Mud | 3·16 (422·5) | 1 (ref) | − | 0·60 (274·5) | 1 (ref) | ·· | |
| Cement, wood, or metal | 2·98 (370·2) | 0·97 (0·79–1·19) | 0·74 | 0·49 (248·1) | 0·89 (0·67–1·17) | 0·40 | |
| Eaves | |||||||
| Open | 3·15 (269·6) | 1 (ref) | ·· | 0·59 (187·2) | 1 (ref) | ·· | |
| Closed | 3·04 (523·1) | 1·01 (0·80–1·28) | 0·91 | 0·52 (335·4) | 0·90 (0·68–1·20) | 0·48 | |
| All household data | |||||||
| House typeठ| |||||||
| Traditional (2013 and 2016) | 3·15 (434·3) | 1 (ref) | ·· | 0·61 (282·8) | 1 (ref) | ·· | |
| Traditional (2013) and modern (2016) | 2·93 (242·3) | 0·90 (0·73–1·11) | 0·34 | 0·47 (164·5) | 0·81 (0·57–1·15) | 0·24 | |
| Modern (2013 and 2016) | 2·80 (101·7) | 0·84 (0·58–1·23) | 0·37 | 0·50 (68·6) | 0·93 (0·65–1·35) | 0·72 | |
*
Malaria incidence per person-years=new malaria episodes/person years of observation.
†
Incidence rate ratio (IRR) adjusted for mean age during follow-up (continuous variable), sex, and household socioeconomic position.
‡
Modern houses were defined as those with a cement, wood, or metal wall, tiled or metal roof, and closed eaves; all other houses were defined as traditional.
§
Before indoor residual spraying, IRR adjusted for 2013 household socioeconomic position and after indoor residual spraying, IRR adjusted for 2016 household socioeconomic position.