Table 4.
Association Between Respondent Plasmodium Infection and at Least Weekly Contact With Plasmodium-Infected Individual (Model A), and Respondent’s Household Plasmodium Infection Status and at Least Weekly Contact With Any Member of a Plasmodium-Positive Household (Model B), by Location of Contact
| Individual Contact Models | ORa | (95% CI) | P Value | Household Contact Models | ORa | (95% CI) | P Value |
|---|---|---|---|---|---|---|---|
| A1. Contact’s Plasmodium status, weekly contact | B1. Contact’s household status, weekly contact | ||||||
| Plasmodium negative, <weekly contact | Ref | … | HH Plasmodium negative, <weekly contact | Ref | … | ||
| Plasmodium negative, ≥weekly contact | 1.16 | (.39–3.43) | .79 | HH Plasmodium negative, ≥weekly contact | 1.28 | (.34–4.8) | .72 |
| Plasmodium positive, <weekly contact | 1.05 | (.14–7.73) | .96 | HH Plasmodium positive, <weekly contact | 1.01 | (.26–4.01) | .99 |
| Plasmodium positive, ≥weekly contact | 1.06 | (.15–7.38) | .95 | HH Plasmodium positive, ≥weekly contact | 1.36 | (.35–5.36) | .66 |
| A2. Contact’s Plasmodium status, weekly contact at respondent’s household | B2. Contact’s household status, weekly contact at respondent’s household | ||||||
| Plasmodium negative, <weekly hh contact | Ref | … | HH Plasmodium negative, <weekly hh contact | Ref | … | ||
| Plasmodium negative, ≥weekly hh contact | 0.85 | (.19–3.82) | .84 | HH Plasmodium negative, ≥weekly hh contact | 0.77 | (.14–4.33) | .77 |
| Plasmodium positive, <weekly hh contact | 0.96 | (.22–4.06) | .95 | HH Plasmodium positive, <weekly hh contact | 0.97 | (.42–2.25) | .95 |
| Plasmodium positive, ≥weekly hh contact | 1.06 | (.03–35.62) | .97 | HH Plasmodium positive, ≥weekly hh contact | 0.94 | (.15–5.86) | .95 |
| A3. Contact’s Plasmodium status, weekly contact at farms/fields | B3. Contact’s household status, weekly contact at farms/fields | ||||||
| Plasmodium negative, <weekly ff contact | Ref | … | HH Plasmodium negative, <weekly ff contact | Ref | … | ||
| Plasmodium negative, ≥weekly ff contact | 1.38 | (.42–4.53) | .59 | HH Plasmodium negative, ≥weekly ff contact | 1.23 | (.28–5.49) | .79 |
| Plasmodium positive, <weekly ff contact | 0.97 | (.23–4.04) | .97 | HH Plasmodium positive, <weekly ff contact | 0.95 | (.37–2.47) | .92 |
| Plasmodium positive, ≥weekly ff contact | 1.18 | (.07–19.15) | .91 | HH Plasmodium positive, ≥weekly ff contact | 1.47 | (.32–6.73) | .62 |
Abbreviations: CI, confidence interval; ff, farm and field; hh, respondent’s household; HH, contact’s household; OR, odds ratio.
aORs adjusted for village to control for differences in malaria prevalence between the 3 villages. Effect of social contact with a Plasmodium-infected individual on respondent’s risk of Plasmodium infection should be apparent as an OR significantly greater than 1 for exposure to a Plasmodium-positive individual with whom contact occurs at least weekly. All other ORs should approximately equal 1.