Table 2. Factors associated with estimated parasite load in blood of T. cruzi-infected mothers at the time of delivery.
| Parasite load (parasites/mL) a | |||||
|---|---|---|---|---|---|
| Factor | >35 | 1–34 | < 1 | Median (IQR) | P value |
| Twin birth | |||||
| Yes | 4 (57.1%) | 1 (14.3%) | 2(28.6%) | 47.7 (0–96.5) | 0.07 b |
| No | 25 (22.1%) | 25 (22.1%) | 63 (55.8%) | 0 (0–32.2) | |
| Current house is infested | |||||
| Yes | 1 (5.6%) | 4 (22.2%) | 13 (72.2%) | 0 (0–1.4) | 0.05 b |
| No | 28 (27.5%) | 22 (21.6%) | 52 (51.0%) | 0 (0–46.4) | |
| Age (years) | |||||
| 13–19 | 4 (36.4%) | 2 (18.2%) | 5 (45.5%) | 0.16 (0, 141) | 0.74 c |
| 20–29 | 14 (25.0%) | 20 (35.7%) | 22 (39.3%) | 1.1 (0, 35.6) | |
| 30–46 | 11 (22.0%) | 16 (32.0%) | 23 (46.0%) | 0.4 (0, 32.2) | |
| Median (IQR) age | 25 (21, 34) | 29 (24, 34) | 29 (22, 34) | 0.40 c | |
| Lived in infested house | |||||
| Ever | 9 (13.9%) | 11 (16.9%) | 45 (69.1%) | 0 (0–9.2) | 0.0002 b |
| Never | 20 (37.0%) | 15 (27.8%) | 19 (35.2%) | 26.4 (0–64.1) | |
| Median (IQR) years | 0 (0–7.0) | 0 (0–16.0) | 12.5 (0–20.5) | 0.0005 c | |
| Lived in house with thatch roof | |||||
| Ever | 7 (14.0%) | 9 (18.0%) | 34 (68.0%) | 0 (0–9.2) | 0.007 b |
| Never | 22 (31.4%) | 17 (24.3%) | 31 (44.3%) | 19.5 (0–62.0) | |
| Median (IQR) years | 0 (0–0) | 0 (0–13.0) | 1.0 (0–13.0) | 0.02 c | |
| Lived in house with mud walls | |||||
| Ever | 7 (12.3%) | 11 (19.3%) | 39 (68.4%) | 0 (0–9.2) | 0.001 b |
| Never | 22 (34.9%) | 15 (23.8%) | 26 (41.3%) | 19.9 (0–62.3) | |
| Median (IQR) years | 0 (0–0) | 0 (0–15.0) | 5.0 (0–15.0) | 0.004 c | |
| Lived in house with earth floor | |||||
| Ever | 9 (15.0%) | 10 (16.7%) | 41 (68.3%) | 0 (0–10.7) | 0.002 b |
| Never | 20 (33.3%) | 16 (26.7%) | 24 (40.0%) | 22.3 (0–62.1) | |
| Median (IQR) years | 0 (0–7.0) | 0 (0–15.0) | 8 (0–16.0) | 0.02 c | |
| Lived in rural area | |||||
| Ever | 18 (26.9%) | 24 (35.8%) | 25 (37.3%) | 4.2 (0, 51.7) | 0.75 b |
| Never | 11 (28.2%) | 10 (25.6%) | 18 (46.2%) | 0.2 (0, 46.4) | |
| Median (IQR) years | 7 (0, 18) | 11 (0, 16) | 4 (0, 17) | 0.80 c | |
The limit of detection for the quantitative PCR assay was 1 parasite/mL. Parasite load values below this cutoff were assumed to be 0 for the purpose of analysis.
aqPCR data were missing for 2 women who transmitted and 6 women who did not transmit to their infants. Four mother-infant pairs with ambiguous transmission status are excluded (see text).
bComparison of parasite load distributions by maternal characteristic by Wilcoxon signed rank test.
cComparison of years of exposure by parasite load category by Kruskal-Wallis test.