TABLE 1.
Human serum specimens received at the CDC for diagnosis of CSD by IFA
| Serum no. | IFA titera for:
|
|
|---|---|---|
| B. henselae | B. quintana | |
| S1 | 31 | 31 |
| S2 | 31 | 31 |
| S3 | 128 | 128 |
| S4 | 64 | 512 |
| S5 | 512 | 8,192 |
| S6 | 31 | 31 |
| S7 | 8,192 | 8,192 |
| S8 | 8,193 | 8,193 |
| S9 | 8,193 | 8,193 |
| S10 | 31 | 31 |
| S11 | 31 | 31 |
| S12 | 2,048 | 8,192 |
| S13 | 2,048 | 8,192 |
| S14 | 512 | 512 |
| S15 | 8,192 | 8,193 |
| S16 | 8,193 | 8,193 |
| S17 | 31 | 31 |
| S18 | 2,048 | 2,048 |
a
Titers are reported as the reciprocal of serum dilutions; 31 is the convention for <32. An intense signal at 8,192 (the highest dilution tested) is considered to be >8,192. Thus, 8,193 is the convention for >8,192.