TABLE 4.
NP colonization with NTHI 12 in convalescent animals or animals that received i.m. immunizations with inactivated NTHI whole cells
| Group | Animals | No. of infected animals/total no. of animals challenged (%)a | Mean CFU/25-μl nasal lavage | Median CFU/25-μl nasal lavage |
|---|---|---|---|---|
| 1 | Convalescent | 0/9 (0)b | 0c | 0d |
| 2 | 0/6 (0)b | 0c | 0d | |
| 3 | Immunized with strain 12 | 3/10 (30.0)b | 14c | 4d |
| 4 | 1/8 (12.5)b | 10c | 3d | |
| 5 | Immunized with strain LCDC2 | 4/9 (44) | 129c | 63d |
| 6 | 4/9 (44) | 135c | 75d | |
| 7 | Control | 9/10 (90.0) | 550 | 600 |
| 8 | 8/9 (88.9) | 680 | 600 |
a
Infected animals are defined as having >10 CFU of bacteria recovered from 25 μl of nasal lavage fluid.
b
Statistical significance compared to control animals (P < 0.05) in the Fisher exact test.
c
Statistical significance in Student’s unpaired t test.
d
Statistical significance in the Mann-Whitney rank sum test.