Table 3.
Unadjusted and adjusted logistic regression for the risk factors associated with having an asymptomatic Plasmodium falciparum infection compared with being negative (microscopy and PCR) for a P. falciparum infection
| Factor | Asymptomatic P. falciparum prevalence (N = 3,768)* |
|||
|---|---|---|---|---|
| Unadjusted |
Adjusted |
|||
| OR (95% CI) | P value | OR (95% CI) | P value | |
| Survey | ||||
| Survey 1 (October 2012) | 1.00 | – | 1.00 | – |
| Survey 2 (June 2013) | 0.25 (0.22–0.29) | < 0.001 | 0.19 (0.16–0.23) | < 0.001 |
| Age groups | ||||
| 1–5 years | 1.00 | – | 1.00 | – |
| 6–10 years | 2.10 (1.69–2.60) | < 0.001 | 2.33 (1.85–2.93) | < 0.001 |
| 11–20 years | 2.43 (1.96–3.02) | < 0.001 | 2.67 (2.11–3.38) | < 0.001 |
| 21–39 years | 0.78 (0.63–0.97) | 0.023 | 0.73 (0.58–0.93) | 0.009 |
| ≥ 40 years | 0.69 (0.57–0.85) | < 0.001 | 0.68 (0.55–0.85) | 0.001 |
| Gender | ||||
| Female | 1.00 | – | 1.00 | – |
| Male | 1.60 (1.41–1.83) | < 0.001 | 1.50 (1.30–1.73) | < 0.001 |
| Catchment area | ||||
| Vea/Gowrie | 1.00 | – | 1.00 | – |
| Soe | 1.38 (1.21–1.57) | < 0.001 | 1.57 (1.36–1.82) | < 0.001 |
| Bed net usage previous night | ||||
| No | 1.00 | – | † | |
| Yes | 0.95 (0.78–1.15) | 0.577 | ||
| Antimalarial treatment (previous 2 weeks) | ||||
| No treatment | 1.00 | – | 1.00 | – |
| Treatment | 0.72 (0.62–0.84) | < 0.001 | 0.67 (0.56–0.82) | < 0.001 |
CI = confidence interval; OR = odds ratio; PCR = polymerase chain reaction.
*
Asymptomatic data reflect the combined prevalence of both microscopic and 18S rRNA PCR-positive samples for P. falciparum (includes P. falciparum mixed infections).
†
Variables not introduced in the final adjusted model.