Table 1.
Demographic Characteristics of 1,933 Household Contacts of Tuberculosis Cases, Stratified by the HIV Serostatus of the Index Case
| Variable | Household Contacts of HIV-Seropositive Tuberculosis Cases [n (%)]* | Household Contacts of HIV-Seronegative Tuberculosis Cases [n (%)]* | All Contacts [n (%)]* | P Value† |
|---|---|---|---|---|
| Household contact characteristics | ||||
| N | 915 (47.3) | 1,018 (52.7) | 1,933 (100) | — |
| Median age, yr (IQR) | 11 (5–20) | 12 (5–22) | 12 (5–21) | 0.55 |
| Age group, yr | 0.05 | |||
| 0–4 | 185 (20.2) | 251 (24.7) | 436 (22.6) | |
| 5–14 | 368 (40.2) | 352 (34.6) | 720 (37.3) | |
| 15–24 | 182 (19.9) | 214 (21.0) | 396 (20.5) | |
| 25–34 | 102 (11.2) | 97 (9.5) | 199 (10.3) | |
| 35–44 | 44 (4.8) | 57 (5.6) | 101 (5.2) | |
| ≥45 | 34 (3.7) | 47 (4.6) | 81 (4.2) | |
| Sex | 0.51 | |||
| Male | 398 (43.5) | 455 (44.7) | 853 (44.5) | |
| Education level | 0.05 | |||
| None | 296 (32.4) | 365 (35.9) | 661 (34.2) | |
| Primary | 436 (47.7) | 428 (42.0) | 864 (44.7) | |
| Secondary or higher | 183 (20.0) | 225 (22.1) | 408 (21.1) | |
| Nutritional status‡ | 0.39 | |||
| Underweight | 25 (2.7) | 30 (3.0) | 55 (2.9) | |
| Normal | 813 (88.9) | 885 (86.9) | 1,698 (87.8) | |
| Overweight | 73 (8.0) | 93 (9.1) | 166 (8.6) | |
| Missing | 4 (0.4) | 10 (1.0) | 14 (0.7) | |
| BCG vaccinated§ | 0.97 | |||
| Yes | 643 (70.3) | 711 (69.8) | 1,354 (70.1) | |
| No | 236 (25.8) | 270 (26.5) | 506 (26.2) | |
| Unknown | 32 (3.5) | 33 (3.2) | 65 (3.4) | |
| Missing | 4 (0.4) | 4 (0.4) | 8 (0.4) | |
| Cigarette smoker | 0.60 | |||
| Yes | 54 (5.9) | 53 (5.2) | 107 (5.5) | |
| No | 657 (71.8) | 751 (73.8) | 1,408 (72.8) | |
| Missing | 204 (22.3) | 214 (21.0) | 418 (21.6) | |
| Relation to index case | <0.01 | |||
| Spouse | 129 (14.1) | 126 (12.4) | 255 (13.2) | |
| Parent | 24 (2.6) | 47 (4.6) | 71 (3.7) | |
| Child | 411 (44.9) | 405 (39.8) | 816 (42.2) | |
| Sibling | 78 (8.6) | 124 (12.2) | 202 (10.5) | |
| Other|| | 270 (29.6) | 312 (30.7) | 583 (30.1) | |
| Missing | 3 (0.3) | 4 (0.4) | 7 (0.4) | |
| Past active tuberculosis | 0.84 | |||
| Yes | 12 (1.3) | 14 (1.4) | 26 (1.4) | |
| No | 897 (98.0) | 995 (97.7) | 1,892 (97.9) | |
| Missing | 6 (0.7) | 9 (0.9) | 15 (0.8) | |
| Alcohol usage | 0.26 | |||
| Yes | 133 (14.5) | 123 (12.1) | 256 (13.2) | |
| No | 778 (85.0) | 889 (87.3) | 1,667 (86.2) | |
| Missing | 4 (0.4) | 6 (0.6) | 10 (0.5) | |
| HIV serostatus | <0.01 | |||
| Positive | 154 (16.8) | 47 (4.6) | 201 (10.4) | |
| Negative | 639 (69.8) | 814 (80.0) | 1,455 (75.2) | |
| Missing | 122 (13.3) | 157 (15.4) | 279 (14.4) | |
| Closeness to index case | 0.37 | |||
| Share bed | 155 (16.9) | 182 (17.9) | 337 (17.4) | |
| Share room, not bed | 404 (44.2) | 414 (40.7) | 818 (42.3) | |
| Different room | 336 (36.7) | 404 (39.7) | 740 (38.3) | |
| Missing | 20 (2.2) | 18 (1.8) | 38 (2.0) | |
| Tuberculosis infection¶ | ||||
| Latent tuberculosis infection | 577 (65.7) | 717 (73.6) | 1,294 (69.9) | 0.01 |
| Coprevalent tuberculosis | 37 (4.0) | 44 (4.3) | 81 (4.2) | 0.76 |
| All infection | 614 (67.1) | 761 (74.8) | 1,375 (71.1) | <0.01 |
| Index case characteristics | ||||
| Age group, yr | <0.01 | |||
| 18–29 | 290 (31.7) | 606 (59.5) | 896 (46.3) | |
| 30–39 | 401 (43.8) | 232 (22.8) | 633 (32.8) | |
| 40–49 | 176 (19.2) | 115 (11.3) | 291 (15.1) | |
| ≥50 | 48 (5.3) | 65 (6.4) | 113 (5.9) | |
| Sex | 0.22 | |||
| Male | 465 (50.8) | 546 (53.6) | 1,011 (52.3) | |
| Female | 450 (49.2) | 472 (46.4) | 922 (47.7) | |
| Cigarette smoker | 0.53 | |||
| Yes | 210 (23.0) | 212 (20.8) | 422 (21.8) | |
| No | 696 (76.1) | 796 (78.2) | 1,492 (77.2) | |
| Missing | 9 (1.0) | 10 (1.0) | 19 (1.0) | |
| Sputum smear status | <0.01 | |||
| Negative | 241 (26.3) | 205 (20.1) | 446 (23.1) | |
| Positive | 674 (73.7) | 813 (80.0) | 1,487 (77.0) | |
| Chest radiograph findings** | <0.01 | |||
| Normal | 52 (5.7) | 48 (4.7) | 100 (5.2) | |
| Minimal | 106 (11.6) | 71 (7.0) | 177 (9.2) | |
| Moderately advanced | 372 (40.7) | 269 (26.4) | 641 (33.2) | |
| Far advanced | 380 (41.5) | 609 (59.8) | 989 (51.2) | |
| Missing | 5 (0.6) | 21 (2.1) | 26 (1.4) | |
| Lung cavitation** | <0.01 | |||
| Cavitary disease | 422 (46.1) | 697 (68.5) | 1,119 (57.9) | |
| Noncavitary disease | 480 (52.5) | 283 (27.8) | 763 (39.5) | |
| Missing | 13 (1.4) | 38 (3.7) | 51 (2.6) | |
| Duration of cough | 0.15 | |||
| <30 d | 49 (5.4) | 69 (6.8) | 118 (6.1) | |
| ≥30 and <60 d | 201 (22.0) | 220 (21.6) | 421 (21.8) | |
| ≥60 and <90 d | 222 (24.3) | 215 (21.1) | 437 (22.6) | |
| ≥90 d | 421 (46.0) | 499 (49.0) | 920 (47.6) | |
| Missing | 22 (2.4) | 15 (1.5) | 37 (1.9) | |
| Household characteristics | ||||
| Housing type | <0.01 | |||
| Muzigo†† | 474 (51.8) | 412 (40.5) | 887 (45.8) | |
| Single-family household | 434 (47.4) | 600 (58.9) | 1,037 (54.5) | |
| Missing | 7 (0.8) | 6 (0.6) | 13 (0.7) | |
| Charcoal or fire smoke exposure | <0.01 | |||
| Inside household | 162 (17.7) | 246 (24.2) | 408 (21.1) | |
| Outside household | 680 (74.3) | 675 (66.3) | 1,355 (70.1) | |
| None | 60 (6.6) | 71 (7.0) | 131 (6.8) | |
| Missing | 13 (1.4) | 26 (2.6) | 39 (2.0) | |
| Ventilation, No. windows per room | 0.08 | |||
| >1 | 168 (18.4) | 229 (22.5) | 397 (20.5) | |
| ≤1 | 740 (80.9) | 783 (76.9) | 1,523 (78.8) | |
| Missing | 7 (0.8) | 6 (0.6) | 13 (0.7) | |
| Family size, No. in household | 0.26 | |||
| 1–5 | 405 (44.3) | 465 (45.7) | 870 (45.0) | |
| 6–10 | 408 (44.6) | 421 (41.4) | 829 (42.9) | |
| >10 | 102 (11.2) | 132 (13.0) | 234 (12.1) |
Definition of abbreviations: BCG = bacillus Calmette-Guérin; BMI = body mass index; IQR = interquartile range.
Percentages refer to within–characteristic column totals among contacts of HIV-seropositive and -seronegative tuberculosis index patients. Percentages may not total 100% because within-column percentages were rounded to the nearest integer.
We used Pearson chi-square tests to derive P value for all categorical variables. For continuous variables, we used Wilcoxon rank sum tests for comparison of two-sample medians.
Nutritional status was assessed for each contact through BMI measurements for adults greater than or equal to 18 years of age and through weight-for-age z scores for child contacts. Individuals were classified as underweight if their z score was less than −2 or a BMI less than 18.5, normal weight if z scores were between −2 and 2 or their BMI was greater than or equal to 18.5 and less than 25, and overweight if z scores were greater than 2 or BMI was greater than or equal to 25.
Evaluated through BCG scar, verified by medical records when available.
Includes other relatives, such as grandparents, grandchildren, aunts, uncles, and cousins. Also includes nonrelatives living in the household.
The denominator for “Latent tuberculosis infection” was household contacts without coprevalent disease (n = 1,852). The denominator for the “Coprevalent tuberculosis disease” row was all household contacts (n = 1,933). The “All infection” row included contacts with either latent tuberculosis infection or coprevalent disease; the denominator for this row includes all household contacts (n = 1,933). Latent tuberculosis infection was defined as a tuberculin skin test induration reaction greater than or equal to 10 mm. Coprevalent tuberculosis disease was defined as the identification of tuberculosis disease at or within 3 months of the baseline household visit.
Radiographic imaging results were graded by an experienced clinician using the 1961 National Tuberculosis Association classification system.
Muzigo households are defined as multifamily household units in the same building.