Table 1.
Characteristics of study participants
| Characteristics | Urban survey n/N (%)a | Rural survey n/N (%)a | P valueb |
|---|---|---|---|
| Socio‐demographic | |||
| Age in (y), median (IQR) | 20 (8, 31) | 24 (8, 34) | 0.329c |
| Male sex | 688/1610 (42.7) | 1738/3350 (49.5) | 0.002 |
| Place of birth | |||
| City | 53/513 (10.3) | 61/2406 (2.9) | |
| Town | 138/513 (26.9) | 254/2406 (10.4) | |
| Village | 322/513 (62.7) | 2091/2406 (86.7) | <0.001 |
| Maternal tribe, larger region grouping | |||
| Central Uganda | 605/1331 (45.5) | 1197/3304 (36.5) | |
| Other, Ugandan | 607/1331 (45.6) | 1588/3304 (48.1) | |
| Non‐Ugandan, African | 119/1331 (8.9) | 519/3304 (15.4) | 0.020 |
| Paternal tribe, larger region grouping | |||
| Central Uganda | 593/1334 (44.5) | 1343/3317 (39.8) | |
| Other, Ugandan | 624/1334 (46.8) | 1556/3317 (47.5) | |
| Non‐Ugandan, African | 117/1334 (8.7) | 418/3317 (12.7) | 0.208 |
| Maternal history of allergies (general) | 93/1187 (7.8) | 366/2930 (12.7) | <0.001 |
| Paternal history of allergies (general) | 30/1117 (2.6) | 171/2796 (5.7) | 0.005 |
| Maternal history of asthma | 27/1266 (2.1) | 93/2931 (3.4) | 0.167 |
| Paternal history of asthma | 27/1218 (2.2) | 62/2796 (2.3) | 0.950 |
| Maternal history of eczema | 35/1229 (2.8) | 131/2931 (4.5) | 0.206 |
| Paternal history of eczema | 15/1159 (1.3) | 96/2795 (2.9) | 0.028 |
| Occupation, grouped by type | |||
| Student or child (not at school) | 662/1338 (49.5) | 1166/3323 (36.7) | |
| Unemployed or housewife | 292/1338 (21.8) | 301/3323 (8.7) | |
| Agricultural, fishing or lake related | 60/1338 (4.5) | 1389/3323 (38.8) | |
| Professional or service providers (Shops, saloons, bars, restaurants, entertainment) | 324/1338 (24.2) | 467/3323 (15.6) | <0.001 |
| Helminth infections | |||
| S mansoni (KK) | 86/1197 (7.2) | 846/2751 (31.8) | <0.001 |
| S mansoni intensity (KK) | |||
| Uninfected | 1111/1197 (92.8) | 1905/2751 (68.2) | |
| Low | 41/1197 (3.4) | 425/2751 (15.7) | |
| Moderate | 31/1197 (2.6) | 231/2751 (9.1) | |
| Heavy | 14/1197 (1.1) | 190/2751 (7.1) | <0.001 |
| S mansoni (urine CCA) | 581/1318 (44.1) | 2445/2879 (85.6) | <0.001 |
| S mansoni (PCR) | 204/1191 (17.1) | 1338/2747 (50.0) | <0.001 |
| A lumbricoides (KK) | 0/1197 (0.0) | 14/2751 (0.4) | |
| Trichuris trichiura (KK) | 21/1196 (1.8) | 245/2751 (7.8) | <0.001 |
| N americanus (PCR) | 56/1191 (4.7) | 259/2747 (8.4) | 0.016 |
| S stercoralis (PCR) | 29/1191 (2.4) | 190/2747 (6.2) | <0.001 |
| Schistosoma‐specific antibody levels | |||
| SEA‐specific IgE (μg/mL), median (IQR) | 2.7 (2.6, 2.8) | 4.6 (4.3, 4.8) | <0.001c |
| SWA‐specific IgE (μg/mL), median (IQR) | 2.2 (2.1, 2.4) | 4.9 (4.6, 5.1) | <0.001c |
| SEA‐specific IgG4 (μg/mL), median (IQR) | 30.8 (27.8, 37.3) | 278.6 (228.7, 322.4) | <0.001c |
| SWA‐specific IgG4 (μg/mL), median (IQR) | 42.7 (40.5, 44.1) | 108.6 (98.3, 124.7) | <0.001c |
| SEA‐specific IgG (μg/mL), median (IQR) | 777.9 (744.6, 806.1) | 1975.4 (1848.0, 2096.4) | <0.001c |
| SWA‐specific IgG (μg/mL), median (IQR) | 795.4 (771.2, 828.6) | 1497.2 (1429.4, 1561.5) | <0.001c |
| Allergy‐related outcomes | |||
| Skin prick test reactivity | |||
| Any | 302/1317 (22.9) | 576/3037 (19.1) | 0.054 |
| Dermatophagoides mix | 228/1317 (17.3) | 326/3037 (10.5) | <0.001 |
| B tropicalis | 184/1317 (13.9) | 229/3036 (7.9) | <0.001 |
| B germanica | 186/1320 (14.1) | 350/3035 (11.8) | 0.137 |
| Allergen‐specific IgE (≥0.35 kU/L, ImmunoCAP) | |||
| Any | 148/345 (42.9) | 437/780 (55.1) | 0.007 |
| D pteronyssinus | 104/345 (30.1) | 264/780 (33.2) | 0.421 |
| B germanica | 118/345 (34.2) | 393/780 (49.8) | <0.001 |
| A hypogaea | 41/345 (11.8) | 114/780 (14.9) | 0.266 |
| Total IgE (kU/L), median (IQR) | 159 (56, 522) | 672 (249, 1942) | <0.001 |
| Wheeze in last 12 mo, age<5 y | 3/229 (1.3) | 9/547 (1.4) | 0.972 |
| Wheeze in last 12 mo, age ≥ 5 y | 24/1107 (2.2) | 87/2776 (3.2) | 0.190 |
| Visible flexural dermatitis | 22/1435 (1.5) | 5/3111 (0.1) | <0.001 |
| Rhinitis in last 12 mo | 45/1336 (3.4) | 104/3323 (3.2) | 0.806 |
| Urticarial rash in last 12 mo | 53/1336 (3.9) | 334/3322 (9.9) | <0.001 |
| Other | |||
| Any worm treatment in the last 12 mo | 795/1296 (61.3) | 2938/3307 (87.7) | <0.001 |
| Malaria treatment in the last 12 mos | 506/1336 (37.8) | 1993/3323 (60.8) | <0.001 |
| P falciparum positivity by blood smear | 3/1347 (0.2) | 102/2923 (3.7) | <0.001 |
| HIV infection | 66/1339 (4.9) | 402/2399 (17.3) | <0.001 |
CCA: circulating cathodic antigen; IQR: interquartile range; KK: Kato‐Katz; PCR: polymerase chain reaction; SEA: Schistosoma egg antigen; SWA: Schistosoma adult worm antigen.
a
Percentages adjusted for survey design. Percentages that are significantly higher in one setting compared to the other (P ≤ 0.05) are highlighted in bold. Adjusting for age and sex differences had no significant impact on these differences.
b
P values obtained from survey design‐based logistic regression.
c
P values obtained from survey design‐based linear regression.