Table 1. Epidemiologic characteristics for 1,228 patients with suspected SFTS in rural areas, South Korea*.
| Characteristic |
Total, no. (%) |
Seronegative, no. (%) |
Seropositive, no. (%) |
p value† |
| No. patients | 1,228 (100.0) | 1,178 (95.9) | 50 (4.1) | |
| Area | 0.116 | |||
| Bosung | 416 (33.9) | 393 (94.5) | 23 (5.5) | |
| Dangjin | 411 (33.5) | 400 (97.3) | 11 (2.7) | |
| Hapcheon | 401 (32.7) | 385 (96.0) | 16 (4.0) | |
| Sex | ||||
| M | 442 (36.0) | 425 (96.2) | 17 (3.9) | 0.764 |
| F | 786 (64.0) | 753 (95.8) | 33 (4.2) | |
| Age, y | 0.027 | |||
| <64 | 397 (32.3) | 388 (97.7) | 9 (2.3) | |
| >65 | 831 (67.7) | 790 (95.1) | 41 (4.9) | |
| Education level | 0.489 | |||
| Uneducated (illiterate) | 318 (25.9) | 303 (95.3) | 15 (4.7) | |
| Uneducated (literate) | 165 (13.5) | 158 (95.8) | 7 (4.2) | |
| Elementary school | 361 (29.5) | 343 (95.0) | 18 (5.0) | |
| Middle school | 193 (15.7) | 187 (96.9) | 6 (3.1) | |
| More than high school | 189 (15.4) | 185 (97.9) | 4 (2.1) | |
| Smoking status | 0.324 | |||
| Never | 876 (71.4) | 845 (96.5) | 31 (3.5) | |
| Former | 205 (16.7) | 194 (94.6) | 11 (5.4) | |
| Current | 146 (11.9) | 138 (94.5) | 8 (5.5) | |
| Drinking frequency, no. drinks | 0.587 | |||
| None | 712 (58.0) | 683 (95.9) | 29 (4.1) | |
| <1/mo | 164 (13.4) | 159 (97.0) | 5 (3.1) | |
| <3/wk | 100 (8.1) | 93 (93.0) | 7 (7.0) | |
| 4–6/wk | 148 (12.1) | 143 (96.6) | 5 (3.4) | |
| Every day | 104 (8.5) | 100 (96.2) | 4 (3.9) | |
| Chronic disease | 0.492 | |||
| None | 318 (25.9) | 306 (96.2) | 12 (3.8) | |
| 1 | 417 (34.0) | 403 (96.6) | 14 (3.4) | |
| >2 | 493 (40.2) | 469 (95.1) | 24 (4.9) | |
| Residency duration, y | 0.023 | |||
| 1–20 | 225 (18.3) | 221 (98.2) | 4 (1.8) | |
| 21–40 | 246 (20.0) | 240 (97.6) | 6 (2.4) | |
| >41 | 757 (61.6) | 717 (94.7) | 40 (5.3) | |
| No. family members | 0.074 | |||
| 0 (alone) or 1 | 954 (77.7) | 910 (95.4) | 44 (4.6) | |
| >2 | 274 (22.3) | 268 (97.8) | 6 (2.2) | |
| Raising livestock‡ | 0.352 | |||
| No | 973 (79.2) | 936 (96.2) | 37 (3.8) | |
| Yes | 255 (20.8) | 242 (94.9) | 13 (5.1) | |
| Grazing livestock | 0.165 | |||
| Yes | 119 (9.7) | 117 (98.3) | 2 (1.7) | |
| No | 1109 (90.3) | 1061 (95.7) | 48 (4.3) | |
| Occupation | 0.437 | |||
| Agriculture | 713 (58.1) | 680 (95.4) | 33 (4.6) | |
| Stock farming | 31 (2.5) | 30 (96.8) | 1 (3.2) | |
| Housewife | 85 (6.9) | 80 (94.1) | 5 (5.9) | |
| Farm housewife | 160 (13.0) | 154 (96.3) | 6 (3.8) | |
| Other | 239 (19.5) | 234 (97.9) | 5 (2.1) | |
| Career duration, y | 0.006 | |||
| 1–20 | 433 (35.3) | 423 (97.7) | 10 (2.3) | |
| 21–40 | 256 (20.9) | 249 (97.3) | 7 (2.7) | |
| >41 | 539 (43.9) | 506 (93.9) | 33 (6.1) | |
| Tick bite during lifetime | 0.171 | |||
| Yes | 166 (13.5) | 156 (94.0) | 10 (6.0) | |
| No | 1,062 (86.5) | 1,022 (96.2) | 40 (3.8) | |
| Tick bite during previous year | 0.076 | |||
| Yes | 75 (6.1) | 69 (92.0) | 6 (8.0) | |
| No | 1,153 (93.9) | 1,109 (96.2) | 44 (3.8) | |
| Awareness of SFTS | 0.446 | |||
| Completely unaware | 500 (40.8) | 477 (95.4) | 23 (4.6) | |
| Somewhat aware | 558 (45.5) | 535 (95.9) | 23 (4.1) | |
| Completely aware | 169 (13.8) | 165 (97.6) | 4 (2.4) | |
| History of SFTS or febrile illness during the fall | 0.575 | |||
| Yes | 97 (7.9) | 92 (94.9) | 5 (5.2) | |
| No | 1,130 (92.1) | 1,085 (96.0) | 45 (4.0) | |
| Family history of SFTS or febrile illness during the fall | 0.235 | |||
| Yes | 56 (4.6) | 52 (92.9) | 4 (7.1) | |
| No | 1,171 (95.4) | 1,125 (96.1) | 46 (3.9) | |
| SFTS-related symptoms during the previous 3 y | 0.002 | |||
| Yes | 25 (2.0) | 21 (84.0) | 4 (16.0) | |
| No | 1,202 (98.0) | 1,156 (96.2) | 46 (3.8) |
*SFTS, severe fever with thrombocytopenia syndrome. †By χ2 test. ‡Including cattle, goats, sheep, deer, and birds.