| Characteristics | Number (%) |
| Average age (years) ± SD 34.66 ± 13.1 | |
| sex-ratio M/F 0.95 | |
| sex | |
| male | 611 ((48.91) |
| female | 638 (51.09) |
| Alcohol consumption | |
| Yes | 938 (75.1) |
| NO | 311 (24.9) |
| Habitat | |
| urban | 1060 (84.86) |
| rural | 189 (15.14) |
| Antibody titer group positive | 570 (45.64) |
| 1:160 or less | 244 (42.80) |
| 1:320 to 1:640 | 223 (39.13) |
| 1:1280 to 1:2560 | 103 (18.07) |
| Antibody titer group negative | 679 (54.36) |