Table 1. Characteristics of 1,697 study participants stratified by the presence or absence of any soil-transmitted helminth (STH) infection during the first 3 years of life.
| Characteristic | Uninfected (n = 979) (N, %) | Infected (n = 718) (N, %) | P value | ||
| Child Factors | |||||
| Sex | |||||
| Male | 497 | 50.8% | 357 | 49.7% | 0.671 |
| Gestational age (weeks) [Mean/SD] | 39 | 2 | 39 | 2 | 0.791 |
| Birth order | |||||
| 1–2 | 517 | 52.8% | 306 | 42.6% | |
| 3–4 | 311 | 31.8% | 235 | 32.7% | |
| >5 | 151 | 15.4% | 177 | 24.7% | <0.001 |
| Maternal Factors | |||||
| Age [Mean/SD] | 26 | 6 | 25 | 6 | 0.048 |
| Ethnicity | |||||
| Afro-Ecuadorian | 187 | 19.1% | 259 | 36.1% | <0.001 |
| Other | 792 | 80.9% | 459 | 63.9% | |
| Educational level | |||||
| Illiterate | 103 | 10.5% | 155 | 21.6% | |
| Complete primary | 562 | 57.4% | 448 | 62.4% | |
| Complete secondary | 314 | 32.1% | 115 | 16.0% | <0.001 |
| Paternal Factors | |||||
| Age [Mean/SD] | 30 | 8 | 30 | 9 | 0.516 |
| Ethnicity | |||||
| Afro-Ecuadorian | 175 | 18.3% | 204 | 29.4% | <0.001 |
| Other | 779 | 81.6% | 491 | 70.6% | |
| Educational level | |||||
| Illiterate | 114 | 12.4% | 133 | 20.9% | |
| Complete primary | 486 | 52.8% | 354 | 55.7% | |
| Complete secondary | 321 | 34.9% | 149 | 23.4% | <0.001 |
| Socioeconomic status | |||||
| Low | 328 | 33.5% | 312 | 43.5% | |
| Medium | 303 | 30.9% | 230 | 32% | |
| High | 348 | 35.5% | 176 | 24.5% | <0.001 |
| Environmental Factors | |||||
| Area of residence | |||||
| Urban | 652 | 66.6% | 528 | 73.5% | 0.002 |
| Household overcrowding | |||||
| ≥3 people | 511 | 65.0% | 490 | 80.7% | <0.001 |
| Maternal STH Infections | |||||
| Any STH infection | |||||
| Yes | 346 | 35.5% | 425 | 59.5% | <0.001 |
| A. lumbricoides infection | |||||
| Yes | 184 | 18.9% | 273 | 38.2% | <0.001 |
| A. lumbricoides intensity (epg) | |||||
| Negative | 790 | 81.1% | 441 | 61.7% | |
| Light | 174 | 17.9% | 200 | 28.0% | |
| Moderate | 10 | 1.0% | 67 | 9.4 | |
| Heavy | 0 | 0% | 6 | 0.8% | <0.001 |
| T. trichiura infection | |||||
| Yes | 197 | 20.2% | 279 | 39.1% | <0.001 |
| T. trichiura intensity (epg) | |||||
| Negative | 777 | 79.8% | 438 | 61.2% | |
| Light | 180 | 18.5% | 224 | 31.4% | |
| Moderate | 17 | 1.7% | 47 | 6.6% | |
| Heavy | 0 | 0% | 6 | 0.8% | <0.001 |
| Hookworm | |||||
| Yes | 41 | 4.2% | 63 | 8.8% | <0.001 |
| Paternal STH infection | |||||
| Yes | 82 | 23.9% | 104 | 40.9% | <0.001 |
| Other household member with STH | |||||
| Yes | 408 | 41.7% | 428 | 59.6% | <0.001 |
| Number of stool samples from child | |||||
| 1–4 | 442 | 45.1% | 288 | 40.1% | |
| ≥5 | 537 | 54.9% | 430 | 59.9% | 0.022 |
| Number of anthelmintic treatments* | |||||
| Received by child | |||||
| 0 | 250 | 25.5% | 164 | 22.8% | |
| 1 | 451 | 46.1% | 323 | 45% | |
| ≥2 | 278 | 28.4% | 231 | 32.2% | 0.191 |
P values were calculated using Chi-squared or Student's t tests, as appropriate. Ethnicity ‘other’ represents: mothers; 1,245 Mestizo/6 Indigenous; fathers 1264 Mestizo/6 Indigenous. Socioeconomic status represents tertiles of z scores obtained using a factor analysis. Overcrowding is defined as the number of people living in the household per sleeping room. STH infections were detected using direct saline, Kato-Katz and formol-ether concentration methods. SD – standard deviation. Infection intensities were estimated using the Kato-Katz method. STH infection intensity categories were: A. lumbricoides (light- <5,000 eggs per gramme of stool [epg];; moderate = 5,000–49,999; heavy – ≥50,000); T. trichiura (light - <1,000 epg; moderate – 1,000–9,999; heavy – ≥10,000).
*Treatments with any of: albendazole, mebendazole, oxantel/pyrantel, piperazine, nitazoxanide, and flubendazole. Numbers of missing values (brackets) were: gestational age (312), maternal ethnicity (6), paternal ethnicity (54), paternal educational level (140), household overcrowding (304), maternal STH infection (9), and paternal STH infection (1100).