Table 3. Mixed-effects logistic regression analysis of the association between household (HH) type and risk of Plasmodium vivax infection diagnosed by microscopy or quantitative real-time polymerase chain reaction (qPCR) in Acrelândia, Brazil, 2013.
| Diagnostic method | Regression model | Index HHs vs. Control HHs | Neighbor HHs vs. Control HHs | ||||
|---|---|---|---|---|---|---|---|
| ORa | (95% CI)b | P-value | ORa | (95% CI)b | P-value | ||
| Microscopyc | Univariate | 140.30 | (30.8–639.7) | <0.001 | 30.00 | (7.9–113.9) | <0.001 |
| Model 1e | 141.90 | (32.4–620.9) | <0.001 | 29.80 | (8.1–110.6) | <0.001 | |
| Model 2f | 56.70 | (13.9–231.1) | <0.001 | 18.50 | (5.25–65.5) | <0.001 | |
| qPCRd | Univariate | 5.67 | (3.0–10.7) | <0.001 | 1.93 | (1.3–3.0) | 0.003 |
| Model 1e | 5.95 | (3.2–11.2) | <0.001 | 1.95 | (1.3–3.0) | 0.002 | |
| Model 2f | 3.40 | (1.8–6.3) | <0.001 | 1.61 | (1.1–6.3) | 0.026 | |
aOR = odds ratio.
bCI = confidence interval.
cTotal of 5,866 observations across four rounds of reactive case detection.
dTotal of 5,807 observations across four rounds of reactive case detection.
eAdjusted for age (continuous variable in years), gender, and HH size (<3, 3–5, >5 individuals). Likelihood-ratio test (univariate vs. Model 1), LR = 7.83 (P = 0.098) for microscopy, and LR = 4.39 (P = 0.356) for qPCR.
fAdjusted for all variables included on model 1 plus time of residence in the area (in years), overnight stay in the forest (yes vs. no), and history of slide-confirmed P. vivax infection within the past six months (yes vs. no). Likelihood-ratio test (Model 1 vs. Model 2), LR = 34.20 (P < 0.001) for microscopy, and LR = 50.61 (P < 0.001) for qPCR.