Table 4.
Isolation of optochin-sensitive pneumococcal colonies (number of optochin-sensitive/number of colonies selected), from each of six clinical saliva samples using the standard dilution method compared with the MBS method
| Saliva sample number (Serotype) | Number of optochin-sensitive colonies identified with MBS method | Number of optochin-sensitive colonies identified with standard dilution method |
|---|---|---|
| 1 (15B) | 29/32 | 0/32 |
| 2 (23F) | 4/13 | 1/8 |
| 3 (15B) | 8/8 | 1/8 |
| 4 (19A) | 7/8 | 4/8 |
| 5 (11A) | 8/8 | 3/8 |
| 6 (3)a | 7/8 | 2/8 |
a
Sample 6 (serotype 3) used a modified protocol (SSI antisera only). Pure pneumococcal colonies were identified by a zone of inhibition around the optochin disk (STAR Methods).