Prevalence of Chlamydia pneumoniae antibody in different year groups
| No. (%) positive | ||||
|---|---|---|---|---|
| Year | No. of subjects | IgG ≥1/16 | IgG ≥1/512 | IgM ≥1/16 |
| 1991 | 300 | 180 (60.0) | 9 (3.0) | 0 |
| 1992 | 300 | 189 (63.0) | 10 (3.3) | 2 (0.7) |
| 1993 | 300 | 220 (73.3) | 14 (4.6) | 2 (0.7) |
| 1994 | 300 | 192 (64.0) | 11 (3.6) | 1 (0.3) |
| 1995 | 300 | 191 (63.6) | 10 (3.3) | 0 |
| 1996 | 300 | 177 (59.0) | 8 (2.6) | 0 |
| 1997 | 300 | 187 (62.3) | 10 (3.3) | 1 (0.3) |
| 1998 | 300 | 181 (60.3) | 11 (3.6) | 1 (0.3) |
| 1999 | 300 | 219 (73.0) | 23 (7.6) | 2 (0.7) |
| 2000 | 300 | 193 (64.3) | 15 (5.0) | 1 (0.3) |