Table 2.
Routes of inoculation | Amount of S. pneumoniae: Colony- forming Units (CFU) | Number of rats exhibited meningitis after 5 days | Ratio of meningitic rats with cochleostomy vs. control | Time from inoculation to meningitis (hours) | Number of rats with positive blood culture (S. pneumoniae) | Number of rats with positive CSF culture (S. pneumoniae) | Number of rats with positive left middle ear culture (S. pneumoniae) | Number of rats with positive histological evidence of meningitis |
---|---|---|---|---|---|---|---|---|
Intra-peritoneal (i/p) | 4 x 1010 | 6 | 3:3 | 14 – 15 | 6 | 6 | 0 | 6 |
4 x 108 | 3 | 2:1 | 28 – 30 | 4 | 4 | 4 | 3 | |
4 x 106 | 2 | 0:2 | 51 – 82 | 5 | 3 | 1 | 2 | |
Inner ear | 1 x 107 | 6 | 3:3 | 22 – 26 | 6 | 6 | 6 | 6 |
1 x 105 | 5 | 2:3 | 50 – 54 | 5 | 5 | 6 | 5 | |
1 x 103 | 1 | 0:1 | 72 | 1 | 1 | 1 | 1 | |
Middle ear | 3 x 108 | 4 | 1:3 | 72 – 120 | 6 | 5 | 6 | 4 |
3 x 106 | 2 | 1:1 | 96 | 5 | 2 | 6 | 2 | |
3 x 104 | 0 | N/A | N/A | 2 | 2 | 6 | 0 |
N/A: no rats from both cohort of control and cochleostomy exhibited meningitis.