Table 2:
Associations between endemic Burkitt lymphoma and patient characteristics in Uganda, Tanzania, and Kenya, 2010–2016.
| Uganda | Tanzania | Kenya | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Cases, n (%) | Controls, n (%) | OR* (95% CI) | Cases, n (%) | Controls, n (%) | OR* (95% CI) | Cases, n (%) | Controls, n (%) | OR* (95% CI) | |
| Characteristics | |||||||||
| Season† | |||||||||
| Dry | 138 (42.9) | 731 (63.6) | Ref | 47 (36.7) | 395 (48.2) | Ref | 108 (43.7) | 267 (27.7) | Ref |
| Wet | 184 (57.1) | 419 (36.4) | 2.18 (1.63, 2.92) | 81 (63.3) | 424 (51.8) | 1.49 (1.00, 2.23) | 139 (56.3) | 698 (72.3) | 0.45 (0.33, 0.62) |
| p-value | <0.0001 | 0.050 | <0.0001 | ||||||
| Measures of malaria | |||||||||
| Indoor residual insecticide sprayed in house | |||||||||
| No | 191 (61.0) | 752 (65.7) | Ref | 38 (30.7) | 551 (68.2) | Ref | 190 (81.9) | 880 (92.5) | Ref |
| Yes | 122 (39.0) | 393 (34.3) | 1.02 (0.75, 1.38) | 86 (69.4) | 257 (31.8) | 5.27 (3.43, 8.09) | 42 (18.1) | 71 (7.5) | 3.13 (1.97, 4.96) |
| Missing/Unknown | 9 | 5 | 4 | 11 | 15 | 14 | |||
| p-value | 0.906 | <0.0001 | <0.0001 | ||||||
| Mosquito net ownership and use the night before | |||||||||
| No | 125 (39.8) | 767 (67.1) | Ref | 21 (16.7) | 289 (35.4) | Ref | 44 (18.9) | 322 (33.8) | |
| Yes, but not used | 35 (11.2) | 11 (1.0) | 22.5 (9.94, 51.0) | 17 (13.5) | 30 (3.7) | 8.29 (3.81, 18.1) | 38 (16.3) | 43 (4.5) | 7.09 (3.91, 12.8) |
| Yes, and used | 154 (49.0) | 366 (32.0) | 2.90 (2.12, 3.97) | 88 (69.8) | 497 (60.9) | 2.19 (1.31, 3.67) | 151 (64.8) | 589 (61.7) | 1.90 (1.26, 2.88) |
| Missing/Unknown | 8 | 6 | 2 | 3 | 14 | 11 | |||
| p-value | <0.0001 | <0.0001 | <0.0001 | ||||||
| Regularly uses mosquito insecticide sprays | |||||||||
| No | 298 (95.2) | 1126 (98.4) | Ref | 114 (89.8) | 775 (95.2) | Ref | 226 (97.0) | 924 (97.5) | Ref |
| Yes | 15 (4.8) | 18 (1.6) | 5.62 (2.62, 12.0) | 13 (10.2) | 39 (4.8) | 2.31 (1.15, 4.62) | 7 (3.0) | 24 (2.5) | 1.26 (0.49, 3.26) |
| Missing/Unknown | 9 | 6 | 1 | 5 | 14 | 17 | |||
| p-value | <0.0001 | 0.019 | 0.628 | ||||||
| Malaria rapid diagnostic test | |||||||||
| Negative | 204 (65.4) | 561 (49.0) | Ref | 95 (80.5) | 473 (58.7) | Ref | 192 (84.2) | 542 (57.0) | Ref |
| Positive | 108 (34.6) | 583 (51.0) | 0.44 (0.32, 0.60) | 23 (19.5) | 333 (41.3) | 0.36 (0.22, 0.59) | 36 (15.8) | 409 (43.0) | 0.26 (0.17, 0.39) |
| Missing/Unknown | 10 | 6 | 10 | 13 | 19 | 14 | |||
| p-value | <0.0001 | 0.0001 | <0.0001 | ||||||
| History of fevers, malaria treatment and hospital admission | |||||||||
| Has fever at enrollment | |||||||||
| No | 136 (43.5) | 1122 (97.9) | Ref | 41 (32.3) | 767 (94.0) | Ref | 70 (31.1) | 836 (87.5) | Ref |
| Yes | 177 (56.6) | 24 (2.1) | 49.7 (30.4, 81.2) | 86 (67.7) | 49 (6.0) | 32.1 (19.6, 52.7) | 155 (68.9) | 120 (12.6) | 16.5 (11.1, 24.4) |
| Missing/Unknown | 9 | 4 | 1 | 3 | 22 | 9 | |||
| p-value | <0.0001 | <0.0001 | <0.0001 | ||||||
| ≥1 fever up to 12 months before enrollment | |||||||||
| No | 31 (22.8) | 254 (22.6) | Ref | 11 (26.8) | 115 (15.0) | Ref | 54 (76.1) | 320 (38.2) | Ref |
| Yes | 105 (77.2) | 868 (77.4) | 0.82 (0.51, 1.31) | 30 (73.2) | 652 (85.0) | 0.49 (0.23, 1.03) | 17 (23.9) | 517 (61.8) | 0.22 (0.12, 0.40) |
| Missing/Unknown | 186 | 28 | 87 | 52 | 176 | 128 | |||
| p-value | 0.401 | 0.059 | <0.0001 | ||||||
| ≥1 fever due to malaria up to 6 months before enrollment | |||||||||
| No | 113 (36.2) | 313 (27.3) | Ref | 42 (33.6) | 250 (30.7) | Ref | 108 (48.7) | 288 (30.1) | Ref |
| Yes | 199 (63.8) | 832 (72.7) | 0.56 (0.41, 0.76) | 83 (66.4) | 565 (69.3) | 0.90 (0.60, 1.37) | 114 (51.4) | 668 (69.9) | 0.47 (0.34, 0.65) |
| Missing/Unknown | 10 | 5 | 3 | 4 | 25 | 9 | |||
| p-value | 0.0002 | 0.636 | <0.0001 | ||||||
| ≥1 fever not due to malaria up to 6 months before enrollment | |||||||||
| No | 181 (59.5) | 1062 (92.9) | Ref | 44 (34.9) | 599 (73.6) | Ref | 100 (44.6) | 772 (81.1) | Ref |
| Yes | 123 (40.5) | 81 (7.1) | 8.40 (5.79, 12.2) | 82 (65.1) | 215 (26.4) | 5.17 (3.42, 7.82) | 124 (55.4) | 180 (18.9) | 5.17 (3.67, 7.28) |
| Missing/Unknown | 18 | 7 | 2 | 5 | 23 | 13 | |||
| p-value | <0.0001 | <0.0001 | <0.0001 | ||||||
| ≥1 hospital admission | |||||||||
| No | 112 (35.7) | 626 (54.7) | Ref | 31 (24.4) | 516 (63.2) | Ref | 71 (30.3) | 697 (73.2) | Ref |
| Yes | 202 (64.3) | 519 (45.3) | 2.01 (1.49, 2.70) | 96 (75.6) | 300 (36.8) | 5.45 (3.50, 8.51) | 163 (69.7) | 255 (26.8) | 6.67 (4.70, 9.47) |
| Missing/Unknown | 8 | 5 | 1 | 3 | 13 | 13 | |||
| p-value | <0.0001 | <0.0001 | <0.0001 | ||||||
| Inpatient malaria treatment | |||||||||
| Yes, past 12 months | 24 (7.6) | 150 (13.1) | Ref | 10 (7.9) | 106 (13.0) | Ref | 35 (15.0) | 95 (10.0) | Ref |
| Yes, > 12 months | 82 (26.1) | 269 (23.5) | 2.55 (1.39, 4.67) | 13 (10.2) | 136 (16.7) | 1.15 (0.47, 2.82) | 12 (5.1) | 117 (12.3) | 0.24 (0.11, 0.50) |
| Never | 208 (66.2) | 725 (63.4) | 2.04 (1.17, 3.57) | 104 (81.9) | 574 (70.3) | 1.94 (0.94, 3.99) | 187 (79.9) | 743 (77.8) | 0.55 (0.35, 0.86) |
| Missing/Unknown/Unknown | 8 | 6 | 1 | 3 | 13 | 10 | |||
| p-value | 0.010 | 0.066 | 0.001 | ||||||
| Outpatient malaria treatment | |||||||||
| Yes, past 12 months | 153 (48.9) | 532 (46.5) | Ref | 62 (48.8) | 255 (31.3) | Ref | 106 (45.3) | 539 (56.4) | Ref |
| Yes, > 12 months | 73 (23.3) | 90 (7.9) | 3.69 (2.44, 5.56) | 14 (11.0) | 69 (8.5) | 0.87 (0.45, 1.68) | 23 (9.8) | 64 (6.7) | 1.86 (1.05, 3.28) |
| Never | 87 (27.8) | 523 (45.7) | 0.88 (0.63, 1.24) | 51 (40.2) | 492 (60.3) | 0.44 (0.29, 0.67) | 105 (44.9) | 352 (36.9) | 1.49 (1.06, 2.09) |
| Missing/Unknown | 9 | 5 | 1 | 3 | 13 | 10 | |||
| p-value | <0.0001 | 0.0004 | 0.021 | ||||||
| HIV status | |||||||||
| Negative | 302 (98.1) | 1135 (99.4) | Ref | 114 (96.6) | 775 (99.9) | Ref | 203 (93.1) | 936 (98.4) | Ref |
| Positive | 6 (2.0) | 7 (0.6) | 5.49 (1.52, 19.9) | 4 (3.4) | 1 (0.1) | 25.6 (2.76, 236) | 15 (6.9) | 15 (1.6) | 4.32 (1.90, 9.86) |
| Missing/Unknown | 14 | 8 | 10 | 43 | 29 | 14 | |||
| p-value | 0.009 | 0.004 | 0.001 | ||||||
| Parental characteristics | |||||||||
| Mother’s education | |||||||||
| Up to standard 4 | 200 (63.7) | 581 (50.8) | Ref | 41 (32.3) | 201 (24.6) | Ref | 36 (15.7) | 182 (19.0) | Ref |
| Standard 5–7 | 100 (31.9) | 446 (39.0) | 0.70 (0.51, 0.95) | 82 (64.6) | 570 (69.9) | 0.74 (0.48, 1.13) | 105 (45.7) | 455 (47.6) | 1.36 (0.84, 2.21) |
| ≥ Senior secondary school | 14 (4.5) | 117 (10.2) | 0.51 (0.28, 0.96) | 4 (3.2) | 45 (5.5) | 0.43 (0.14, 1.29) | 89 (38.7) | 319 (33.4) | 1.58 (0.96, 2.61) |
| Missing/Unknown | 8 | 6 | 1 | 3 | 17 | 9 | |||
| p-value | 0.019 | 0.193 | 0.201 | ||||||
| p-trend | 0.005 | 0.070 | 0.079 | ||||||
| Father’s education | |||||||||
| Up to standard 4 | 85 (27.5) | 212 (18.7) | Ref | 35 (27.8) | 111 (13.7) | Ref | 27 (11.8) | 151 (16.1) | Ref |
| Standard 5–7 | 148 (47.9) | 547 (48.3) | 0.73 (0.51, 1.05) | 76 (60.3) | 619 (76.1) | 0.37 (0.23, 0.60) | 86 (37.6) | 371 (39.6) | 1.80 (1.02, 3.15) |
| ≥ Senior secondary school | 76 (24.6) | 373 (33.0) | 0.59 (0.39, 0.89) | 15 (11.9) | 83 (10.2) | 0.55 (0.28, 1.11) | 116 (50.7) | 416 (44.4) | 1.93 (1.11, 3.36) |
| Missing/Unknown | 13 | 18 | 2 | 6 | 18 | 27 | |||
| p-value | 0.040 | <0.001 | 0.063 | ||||||
| p-trend | 0.013 | 0.011 | 0.040 | ||||||
| Mother’s occupation | |||||||||
| Trader/Sales | 11 (3.5) | 94 (8.2) | Ref | 13 (10.2) | 62 (7.6) | Ref | 45 (19.4) | 254 (26.5) | Ref |
| Peasant farmer | 286 (90.8) | 1009 (88.1) | 1.30 (0.65, 2.61) | 103 (81.1) | 724 (88.7) | 0.64 (0.34, 1.23) | 145 (62.5) | 570 (59.6) | 1.39 (0.94, 2.07) |
| Manual laborer | 18 (5.7) | 43 (3.8) | 3.28 (1.28, 8.42) | 11 (8.7) | 30 (3.7) | 1.65 (0.64, 4.21) | 42 (18.1) | 133 (13.9) | 1.48 (0.87, 2.52) |
| Missing/Unknown | 7 | 4 | 1 | 3 | 15 | 8 | |||
| p-value | 0.021 | 0.026 | 0.207 | ||||||
| Father’s occupation | |||||||||
| Trader/Sales | 40 (12.7) | 173 (15.1) | Ref | 22 (17.3) | 100 (12.3) | Ref | 54 (23.4) | 243 (25.4) | Ref |
| Peasant farmer | 243 (77.4) | 831 (72.7) | 0.83 (0.54, 1.27) | 97 (76.4) | 669 (82.1) | 0.60 (0.36, 1.02) | 111 (48.1) | 422 (44.1) | 1.11 (0.75, 1.65) |
| Manual laborer | 31 (9.9) | 139 (12.2) | 1.00 (0.56, 1.79) | 8 (6.3) | 46 (5.6) | 0.75 (0.30, 1.84) | 66 (28.6) | 291 (30.4) | 0.92 (0.60, 1.42) |
| Missing/Unknown | 8 | 7 | 1 | 4 | 16 | 9 | |||
| p-value | 0.535 | 0.161 | 0.602 | ||||||
| Mother’s income, US dollars‡ | |||||||||
| ≤ 7.5 | 213 (66.2) | 565 (49.1) | Ref | 81 (63.3) | 279 (34.1) | Ref | 88 (35.6) | 244 (25.3) | Ref |
| 7.6-≤15.0 | 76 (23.6) | 247 (21.5) | 1.05 (0.74, 1.48) | 30 (23.4) | 260 (31.8) | 0.43 (0.27, 0.69) | 55 (22.3) | 222 (23.0) | 0.76 (0.50, 1.17) |
| >15.0 | 33 (10.3) | 338 (29.4) | 0.33 (0.20, 0.52) | 17 (13.3) | 280 (34.2) | 0.23 (0.13, 0.41) | 104 (42.1) | 499 (51.7) | 0.65 (0.46, 0.93) |
| p-value | <0.0001 | <0.0001 | 0.004 | ||||||
| p-trend | <0.0001 | <0.0001 | 0.021 | ||||||
| Home characteristics | |||||||||
| Distance of home from main road | |||||||||
| Far from the main road | 239 (75.9) | 812 (70.9) | Ref | 73 (57.5) | 642 (78.8) | Ref | 84 (36.2) | 518 (54.1) | Ref |
| Near the main road | 53 (16.8) | 281 (24.5) | 0.86 (0.58, 1.28) | 40 (31.5) | 114 (14.0) | 3.37 (2.13, 5.33) | 96 (41.4) | 332 (34.7) | 2.15 (1.50, 3.08) |
| In town or city | 23 (7.3) | 53 (4.6) | 1.83 (1.02, 3.28) | 14 (11.0) | 59 (7.2) | 2.30 (1.17, 4.50) | 52 (22.4) | 108 (11.3) | 3.30 (2.08, 5.25) |
| Missing/Unknown | 7 | 4 | 1 | 4 | 15 | 7 | |||
| p-value | 0.078 | <0.0001 | <0.0001 | ||||||
| Number of rooms in house | |||||||||
| 1–2 room | 273 (86.9) | 987 (86.1) | Ref | 47 (37.0) | 481 (59.0) | Ref | 116 (50.2) | 539 (56.3) | Ref |
| ≥ 3 rooms | 41 (13.1) | 159 (13.9) | 1.43 (0.94, 2.17) | 80 (63.0) | 335 (41.1) | 2.43 (1.62, 3.63) | 115 (49.8) | 419 (43.7) | 1.46 (1.06, 2.01) |
| Missing/Unknown | 8 | 4 | 1 | 3 | 16 | 7 | |||
| p-value | 0.094 | <0.0001 | 0.021 | ||||||
| Number of children and adult resident | |||||||||
| 2–4 people | 173 (55.1) | 703 (61.3) | Ref | 28 (22.1) | 302 (37.0) | Ref | 48 (20.8) | 257 (26.8) | Ref |
| 5–7 people | 115 (36.6) | 385 (33.6) | 1.45 (1.06, 1.96) | 56 (44.1) | 334 (40.9) | 1.96 (1.18, 3.24) | 125 (54.1) | 500 (52.2) | 1.49 (0.99, 2.24) |
| ≥ 8 people | 26 (8.3) | 58 (5.1) | 2.19 (1.21, 3.97) | 43 (33.9) | 180 (22.1) | 2.81 (1.62, 4.86) | 58 (25.1) | 201 (21.0) | 1.57 (0.97, 2.54) |
| Missing/Unknown | 8 | 4 | 1 | 3 | 16 | 7 | |||
| p-value | 0.006 | 0.001 | 0.120 | ||||||
| p-trend | 0.002 | 0.0002 | 0.060 | ||||||
| Number of people sleeping in the same room as child | |||||||||
| 0–2 people | 49 (15.6) | 202 (17.6) | Ref | 28 (22.1) | 269 (33.0) | Ref | 92 (39.8) | 389 (40.6) | Ref |
| 3 people | 99 (31.5) | 275 (24.0) | 1.55 (0.99, 2.42) | 46 (36.2) | 288 (35.3) | 1.41 (0.84, 2.37) | 83 (35.9) | 259 (27.0) | 1.28 (0.88, 1.85) |
| ≥ 4 people | 166 (52.9) | 669 (58.4) | 1.07 (0.71, 1.63) | 53 (41.7) | 259 (31.7) | 1.88 (1.13, 3.13) | 56 (24.2) | 310 (32.4) | 0.71 (0.47, 1.06) |
| Missing/Unknown | 8 | 4 | 1 | 3 | 16 | 7 | |||
| p-value | 0.058 | 0.049 | 0.022 | ||||||
| p-trend | 0.691 | 0.014 | 0.142 | ||||||
| Connected to electricity grid | |||||||||
| No | 306 (97.1) | 1092 (95.4) | Ref | 122 (96.1) | 745 (91.3) | Ref | 202 (86.7) | 835 (87.6) | Ref |
| Yes | 9 (2.9) | 53 (4.6) | 0.75 (0.26, 2.17) | 5 (3.9) | 71 (8.7) | 0.44 (0.17, 1.13) | 31 (13.3) | 118 (12.4) | 1.22 (0.77, 1.93) |
| Missing/Unknown | 7 | 5 | 1 | 3 | 14 | 12 | |||
| p-value | 0.598 | 0.087 | 0.397 | ||||||
| Source of drinking water | |||||||||
| Unprotected spring/well | 244 (77.5) | 882 (77.0) | Ref | 59 (46.5) | 453 (55.5) | Ref | 130 (55.6) | 572 (59.9) | Ref |
| Protected spring/well | 61 (19.4) | 202 (17.6) | 1.58 (1.07, 2.34) | 42 (33.1) | 218 (26.7) | 1.45 (0.93, 2.27) | 46 (19.7) | 171 (17.9) | 1.43 (0.95, 2.16) |
| Public tap/piped household | 10 (3.2) | 61 (5.3) | 1.05 (0.47, 2.31) | 26 (20.5) | 145 (17.8) | 1.25 (0.74, 2.11) | 58 (24.8) | 212 (22.2) | 1.63 (1.10, 2.40) |
| Missing/Unknown | 7 | 5 | 1 | 3 | 13 | 10 | |||
| p-value | 0.073 | 0.254 | 0.029 | ||||||
| Distance to water source, meters | |||||||||
| < 500 | 38 (12.1) | 383 (33.5) | Ref | 52 (40.9) | 136 (16.7) | Ref | 149 (64.5) | 356 (37.2) | Ref |
| 500–999 | 63 (20.0) | 126 (11.0) | 4.86 (2.93, 8.08) | 22 (17.3) | 159 (19.5) | 0.37 (0.21, 0.65) | 33 (14.3) | 230 (24.0) | 0.32 (0.20, 0.49) |
| 1000–4999 | 122 (38.7) | 511 (44.6) | 2.85 (1.85, 4.37) | 32 (25.2) | 440 (53.9) | 0.16 (0.09, 0.26) | 38 (16.5) | 268 (28.0) | 0.38 (0.25, 0.59) |
| ≥ 5000 | 92 (29.2) | 125 (10.9) | 11.4 (6.83, 19.1) | 21 (16.5) | 81 (9.9) | 0.69 (0.38, 1.27) | 11 (4.8) | 104 (10.9) | 0.18 (0.08, 0.41) |
| Missing/Unknown | 7 | 5 | 1 | 3 | 16 | 7 | |||
| p-value | <0.0001 | <0.0001 | <0.0001 | ||||||
| p-trend | <0.0001 | <0.0001 | <0.0001 | ||||||
Abbreviation: CI = confidence interval
Note: p-values are for heterogeneity
*
Associations are minimally adjusted for age, sex, proximity to water and population density of children 0–15 years.
†
The months of April to June and September to December were classified as wet season months, while the months of January to March and July to August were classified as dry season months.
‡
Income was categorized based on the international poverty line of $1.90 per a day to calculate the average 30-day monthly income. Total household income or father’s income were not analyzed because the results for these were considered unreliable.