Table 3. Predicted outcome of colonization with Stretococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis in young children after upper respiratory tract infection (968 swabs from 212 children; see Table 2)*.
| Parameters | OR (95% CI) |
||
|---|---|---|---|
| S. pneumoniae | H. influenzae | M. catarrhalis | |
| H. influenzae x M. catarrhalis (p = 0.0003)† | |||
| Neither (reference) | 1.0 | – | – |
| H. influenzae only | 0.59 (0.40–0.88) | – | – |
| M. catarrhalis only | 1.31 (0.95–1.81) | – | – |
| Both |
2.13 (1.35–3.38)
|
– |
– |
| S. pneumoniae x M. catarrhalis (p = 0.08)† | |||
| Neither (reference) | – | 1.0 | – |
| S. pneumoniae only | – | 0.52 (0.32–0.83) | – |
| M. catarrhalis only | – | 0.45 (0.29–0.69) | – |
| Both |
– |
0.82 (0.52–1.30) |
– |
| H. influenzae x S. pneumoniae (p<0.0001)† | |||
| Neither (reference) | – | – | 1.0 |
| H. influenzae only | – | – | 0.44 (0.30–0.63) |
| S. pneumoniae only | – | – | 1.22 (0.88–1.70) |
| Both |
– |
– |
2.09 (1.30–3.37)
|
| S. aureus | |||
| Absent (reference) | 1.0 | 1.0 | 1.0 |
| Present |
0.60 (0.36–0.99)
|
0.36 (0.17–0.76)
|
0.72 (0.42–1.25) |
| Age (1-mo increase)‡ |
0.98 (0.96–1.00)
|
1.01 (0.98–1.03) |
0.98 (0.97–1.00)
|
| Antimicrobial drug therapy in past 7 days | |||
| No (reference) | 1.0 | 1.0 | 1.0 |
| Yes |
0.40 (0.22–0.72)
|
1.21 (0.69–2.13) |
0.52 (0.28–0.96)
|
| Time after URI onset, d | |||
| <7 (reference) | 1.0 | 1.0 | 1.0 |
| >7 |
1.47 (0.96–2.27) |
1.10 (0.70–1.73) |
1.21 (0.81–1.80) |
| Gender | |||
| F (reference) | 1.0 | 1.0 | 1.0 |
| M |
1.05 (0.80–1.38) |
1.44 (1.08–.93)
|
0.86 (0.65–1.14) |
| Race | |||
| Not white (reference) | 1.0 | 1.0 | 1.0 |
| White |
1.12 (0.84–1.48) |
0.42 (0.31–0.57)
|
0.80 (0.60–1.07) |
| Day care | |||
| No (reference) | 1.0 | 1.0 | 1.0 |
| Yes |
1.32 (0.97–1.80) |
1.51 (1.09–2.09)
|
1.09 (0.79–1.50) |
| Breast-fed >4 mo | |||
| No (reference) | 1.0 | 1.0 | 1.0 |
| Yes |
0.94 (0.69–1.29) |
0.92 (0.65–1.29) |
0.81 (0.59–1.12) |
| Environmental exposure to tobacco smoke | |||
| No (reference) | 1.0 | 1.0 | 1.0 |
| Yes | 1.13 (0.84–1.52) | 0.93 (0.69–1.27) | 0.91 (0.67–1.23) |
*OR, odds ratio; CI, confidence interval. Significant ORs and 95% CIs are shown in boldface. Each model included variables representing presence or absence of other bacteria as well as all other variables listed. We did not model colonization of S. aureus because of low prevalence of this species (69/968 positive swabs). †p value from logistic regression model for overall significance of bacterial interaction. ‡Age (mo) of the child at the time of swab collection.