Table 1 Risk factors for E. histolytica infection in Hanam province, Vietnam (univariable conditional logistic regression analysis).
Variables | Case | Control | Â | Â | Â |
|---|---|---|---|---|---|
| Â | N (%) | N (%) | Matched OR | 95% CI | P-value |
1. Socio-economic status | Â | Â | Â | Â | Â |
Educational level | Â | Â | Â | Â | Â |
   High school | 6 (13.0) | 17 (12.0) | Reference |  |  |
   Secondary school | 24 (52.2) | 79 (57.3) | 0.8 | 0.7-2.7 | 0.76 |
   Primary school | 16 (34.8) | 42 (29.8) | 1.1 | 0.3-3.8 | 0.87 |
Occupation | Â | Â | Â | Â | Â |
   Non agricultural work | 16 (34.8) | 45 (32.6) | Reference |  |  |
   Agricultural work | 30 (65.2) | 93 (67.4) | 0.8 | 0.3-2.2 | 0.70 |
Household's economic status overall | Â | Â | Â | Â | Â |
   Good | 8 (17.4) | 53 (38.4) | Reference |  |  |
   Average | 22 (47.8) | 39 (28.3) | 3.8 | 1.5-9.8 | 0.01 |
   Poor | 16 (34.8) | 46 (33.3) | 2.4 | 0.9-6.4 | 0.08 |
2. Household sanitary and hygiene conditions | Â | Â | Â | Â | |
Household's sanitary conditions overall | Â | Â | Â | Â | Â |
   Good | 20 (43.5) | 40 (29.0) | Reference |  |  |
   Average | 12 (26.1) | 50 (36.2) | 0.5 | 0.2-1.1 | 0.08 |
   Poor | 14 (30.4) | 48 (34.8) | 0.6 | 0.3-1.3 | 0.21 |
Type of latrine in the household | Â | Â | Â | Â | Â |
   Water latrine (septic tank, biogas) | 15 (32.6) | 47 (34.1) | Reference |  |  |
   Dry latrine (single or double vault) | 29 (63.0) | 87 (63.0) | 1.1 | 0.5-2.2 | 0.89 |
   No latrine | 2 (4.4) | 4 (2.9) | 1.7 | 0.2-11.2 | 0.61 |
Household use of tap water | Â | Â | Â | Â | Â |
   No | 24 (52.2) | 89 (64.5) | Reference |  |  |
   Yes | 22 (47.8) | 49 (35.5) | 1.7 | 0.9-3.4 | 0.13 |
Household use of tube well water | Â | Â | Â | Â | Â |
   No | 16 (34.8) | 53 (38.4) | Reference |  |  |
   Yes | 30 (65.2) | 85 (61.6) | 1.2 | 0.6-2.5 | 0.64 |
Household use of rainwater | Â | Â | Â | Â | Â |
   No | 5 (10.9) | 12 (8.7) | Reference |  |  |
   Yes | 41 (89.1) | 126 (91.3) | 0.8 | 0.3-2.4 | 0.66 |
Close contact with domestic animals in household | Â | Â | Â | Â | |
   No | 9 (19.6) | 42 (30.4) | Reference |  |  |
   Yes | 37 (80.4) | 96 (69.6) | 1.9 | 0.8-4.4 | 0.15 |
3. Exposed to human and animal excreta | Â | Â | Â | Â | |
Composting of human excreta in the household | Â | Â | Â | Â | |
   No | 22 (47.8) | 60 (43.5) | Reference |  |  |
   Yes | 24 (52.2) | 78 (56.5) | 0.8 | 0.4-1.7 | 0.59 |
Use of human excreta for application in field | Â | Â | Â | Â | |
   No | 18 (39.1) | 62 (44.9) | Reference |  |  |
   Yes | 28 (60.9) | 76 (55.1) | 1.3 | 0.6-2.6 | 0.48 |
Handling human excreta in field work | Â | Â | Â | Â | Â |
   No | 22 (47.8) | 61 (44.2) | Reference |  |  |
   Yes | 24 (52.2) | 77 (55.8) | 0.8 | 0.4-1.8 | 0.61 |
Compound with animal husbandry | Â | Â | Â | Â | Â |
   No | 6 (13.0) | 25 (18.1) | Reference |  |  |
   Yes | 40 (87.0) | 113 (81.9) | 1.5 | 0.6-4.0 | 0.42 |
Composting of animal excreta in the compound | Â | Â | Â | Â | |
   No | 31 (67.4) | 79 (57.3) | Reference |  |  |
   Yes | 15 (32.6) | 59 (42.7) | 0.7 | 0.3-1.3 | 0.23 |
Use of animal excreta as fertiliser in the fields | Â | Â | Â | Â | |
   No | 25 (54.3) | 69 (50.0) | Reference |  |  |
   Yes | 21 (45.7) | 69 (50.0) | 0.8 | 0.4-1.7 | 0.59 |
Handling animal excreta in field work | Â | Â | Â | Â | |
   No | 31 (67.4) | 69 (50.0) | Reference |  |  |
   Yes | 15 (32.6) | 69 (50.0) | 0.5 | 0.2-0.9 | 0.03 |
4. Exposed to water from Nhue river and local pond | Â | Â | Â | Â | |
Direct contact with Nhue river water during field work | Â | Â | Â | Â | |
   No | 30 (65.2) | 72 (52.2) | Reference |  |  |
   Yes | 16 (34.8) | 66 (47.8) | 0.6 | 0.3-1.2 | 0.12 |
Use local pond for fishing, bathing, washing | Â | Â | Â | Â | Â |
   No | 32 (69.6) | 95 (68.9) | Reference |  |  |
   Yes | 14 (30.4) | 43 (31.1) | 1.0 | 0.5-2.1 | 0.92 |
Use Nhue river water to irrigate fields | Â | Â | Â | Â | Â |
   No | 1 (2.2) | 13 (9.4) | Reference |  |  |
   Yes | 45 (97.8) | 125 (90.6) | 4.6 | 0.6-35.4 | 0.15 |
5. Personal hygiene habits | Â | Â | Â | Â | Â |
Use protective measures (gloves, boots and face mask) at work | Â | Â | Â | Â | |
   No | 28 (60.9) | 63 (45.6) | Reference |  |  |
   Yes | 18 (39.1) | 75 (54.4) | 0.5 | 0.3-1.1 | 0.07 |
Showering, bathing (with soap) after field work | Â | Â | Â | Â | Â |
   Frequently | 9 (19.6) | 48 (34.8) | Reference |  |  |
   Sometimes | 19 (41.3) | 49 (35.5) | 2.2 | 0.9-5.5 | 0.09 |
   Rarely | 18 (39.1) | 41 (29.7) | 2.3 | 1.0-5.6 | 0.06 |
Washing hands after field work | Â | Â | Â | Â | Â |
   Frequently | 30 (65.2) | 108 (78.3) | Reference |  |  |
   Sometimes | 3 (6.5) | 9 (6.5) | 1.6 | 0.4-7.0 | 0.50 |
   Rarely | 13 (28.3) | 21 (15.2) | 3.4 | 1.2-10.0 | 0.02 |
Washing hands with soap after field work | Â | Â | Â | Â | Â |
   Frequently | 9 (19.6) | 50 (36.2) | Reference |  |  |
   Sometimes | 14 (30.4) | 43 (31.2) | 1.8 | 0.7-5.1 | 0.24 |
   Rarely | 23 (50.0) | 45 (32.6) | 3.0 | 1.2-7.4 | 0.02 |
Eating leftover food from day before | Â | Â | Â | Â | Â |
   No | 13 (28.3) | 42 (30.4) | Reference |  |  |
   Yes | 33 (71.7) | 96 (69.6) | 1.1 | 0.5-2.3 | 0.78 |
Eating raw vegetables the day before | Â | Â | Â | Â | Â |
   No | 44 (95.6) | 130 (94.2) | Reference |  |  |
   Yes | 2 (4.4) | 8 (5.8) | 0.72 | 0.1-3.7 | 0.70 |
Water source for drinking | Â | Â | Â | Â | Â |
   Rainwater | 42 (91.3) | 129 (93.5) | Reference |  |  |
   Tube well water | 4 (8.7) | 9 (6.5) | 1.4 | 0.4-4.9 | 0.61 |