Table 3.
Fully adjusted Cox regression models with follow-up period split at net distribution campaign
| Period 1—week 1 to 48 (n = 7016) | Period 2—week 49 to 101 (n = 6695) | |||
|---|---|---|---|---|
| RR (95% CI) | P value | RR (95% CI) | P value | |
| Increasing household proximity to breeding sitea | 1.60 (1.29–1.98) | < 0.001 | 1.46 (1.17–1.81) | 0.001 |
| Age at study entry | ||||
| ≥ 25 | Ref | Ref | ||
| 15–24 | 2.73 (0.88–8.47) | 0.08 | 1.23 (0.50–3.00) | 0.65 |
| 5–14 | 9.87 (3.79–25.70) | < 0.001 | 2.43 (1.15–5.13) | 0.02 |
| 0–4 | 10.79 (4.03–28.92) | < 0.001 | 4.57 (2.13–9.79) | < 0.001 |
| Gender | ||||
| Males | Ref | Ref | ||
| Females | 0.79 (0.49–1.27) | 0.33 | 0.96 (0.60–1.53) | 0.85 |
| Persons living in household | ||||
| ≤ 7 | Ref | Ref | ||
| ≥ 8 | 0.83 (0.52–1.35) | 0.46 | 1.81 (1.11–2.97) | 0.02 |
| ITN use fraction (%)b | ||||
| > 50 | Ref | Ref | ||
| ≤ 50 | 0.67 (0.37–1.20) | 0.18 | 1.68 (1.01–2.79) | 0.04 |
aDistance to breeding site categorized into: > 2700 m (ref); 2400–2700; 2100–2400; and < 2100 m, and modelled linearly
bITN use was recorded weekly (starting from week 5) during the regular follow-up visits to households. Participants were asked if they slept under a ITN the night before the visit. Use fraction was calculated as the number of nights reportedly sleeping under a ITN divided by the total number of nights asked. During week 48, there was a net distribution campaign in the Kebele thus the follow-up period was split at this point. For those with P. vivax infection, ITN use fraction was calculated only for weeks prior to infection