Table 3. Characteristics of Streptococcus suis cases and controls.
| Characteristics | Cases(n = 101) | Hospital controls(n = 303) | Community controls(n = 300) |
| Sex, n(%) | |||
| Male | 83 (82.2) | 202 (66.7) | 169 (56.3) |
| Female | 18 (17.8) | 101 (33.3) | 131 (43.7) |
| Residence, n(%) | |||
| Rural | 82 (81.2) | 193 (63.7) | 243 (81) |
| Urban | 19 (18.8) | 110 (36.3) | 57 (19) |
| Age (years), median (interquartile range) | 50 (41,59) | 27 (20,40) | 50 (41,6) |
| Occupations related to pigs (1) , n(%) | 21 (20.79) | 8 (2.64) | 8 (2.7) |
| Education level, n(%) | |||
| Primary | 52 (51.5) | 96 (31.7) | 175 (58.3) |
| Secondary “level 2” | 30 (29.7) | 134 (44.2) | 73 (24.3) |
| Secondary “level 3” | 11 (10.9) | 40 (13.2) | 30 (10) |
| University | 1 (1) | 21 (6.9) | 2 (0.7) |
| Illiterate | 6 (5.9) | 12 (4) | 19 (6.3) |
| Religion | |||
| Buddhism | 64 (63.4) | 160 (52.8) | 181 (60.3) |
| Catholicism | 12 (11.8) | 42 (13.9) | 31 (10.3) |
| Christianity | 1 (1) | 4 (1.3) | 0 |
| Cao Dai | 7 (7) | 17 (5.6) | 29 (9.7) |
| Other | 2 (2) | 1 (0.3) | 6 (2) |
| No | 15 (15) | 77 (25.4) | 53 (17.7) |
| Ethnic backgroun | |||
| Kinh | 99 (98.0) | 287 (94.7) | 298 (99.3) |
| Khmer | 1 (1) | 4 (1.3) | 2 (0.7) |
| Chinese | 1 (1) | 4 (1.3) | 0 |
| Other | 0 | 8 (2.6) | 0 |
| Medical history, n(%) | |||
| Diabetes mellitus | 3 (3) | 3 (1) | 4 (1.3) |
| Alcoholism | 14 (13.9) | 18 (5.9) | 20 (6.7) |
| Splenectomy | 1 (1 | 0 | 0 |
| Skin injuries, n(%) | 33 (32.7) | 18 (5.9) | 11 (3.7) |
| Breeding pigs at home, n(%) | 23 (22.8) | 33 (10.9) | 41 (13.7) |
| Any exposure to pigs/pork in the last 2 weeks, n(%) | 46 (45.5) | 39 (12.9) | 55 (18.3) |
| With skin injuries | 20 (19.8) | 5 (1.7) | 2 (0.7) |
| Without skin injuries | 26 (25.7) | 34 (11.2) | 53 (17.7) |
| Eating any “high risk” dish in the last 2 weeks | 48 (47.5) | 66 (21.8) | 48 (16.) |
| Fresh pig blood | 5 (5) | 5 (1.7) | 5 (1.7) |
| Tonsils/tongue | 19 (18.8) | 29 (9.6) | 25 (8.3) |
| Stomach/intestines | 45 (44.6) | 53 (17.5) | 42 (14) |
| Uterus | 8 (7.9) | 8 (2.6) | 13 (4.3) |
| Undercooked pig blood | 11 (10.9) | 18 (5.9) | 5 (1.7) |
| Ill pigs at home in the last 4 weeks, x/n (%) | 10/23 (43.5) | 1/33 (3.0) | 0/40 (0) |
| Pigs at home with S. suis serotype 2 (confirmed by PCR), x/n (2) (%) | 9/22 (40.9) | 3/13 (23.1) | 5/28 (17.9) |
(1)
Butcher, pig breeder, slaughterer, roaster, meat transporter, meat processing, veterinarian and cook.
(2)
Number of households with any number of PCR positive pig swab samples/ number of households where pigs where present and samples were taken.