Table 1.
Characteristics and H. influenzae colonization status of the study population (n = 342)
| Variable | Characteristic | No. of subjects | No. (%) of subjects colonized | Distribution of H. influenzae serotypes among subjects | P valuea |
|---|---|---|---|---|---|
| Age | 6–15 mos | 88 | 21 (23.8) | 20 NT, 1 e | 0.489 |
| 16–23 mos | 67 | 22 (32.8) | 22 NT | ||
| 2 yrs | 59 | 15 (25.4) | 13 NT, 1 b, 1 e | ||
| 3 yrs | 58 | 18 (31.0) | 17 NT, 1 f | ||
| 4 yrs | 43 | 8 (18.6) | 8 NT | ||
| 5 yrs | 24 | 9 (37.5) | 9 NT | ||
| 6 yrs | 3 | 1 (33.3) | 1 NT | ||
| Sex | Male | 185 | 63 (34.1) | 61 NT, 1 b, 1 e | 0.004 |
| Female | 157 | 31 (19.7) | 29 NT, 1 e, 1 f | ||
| Race/ethnicity | White | 49 | 12 (24.5) | 11 NT, 1 e | 0.874 |
| Black | 268 | 78 (29.1) | 75 NT, 1 b, 1 e, 1 f | ||
| Hispanic | 9 | 1 (11.1) | 1 NT | ||
| Asian | 5 | 1 (20.0) | 1 NT | ||
| Other | 10 | 2 (20.0) | 2 NT | ||
| Unknown | 1 | 0 (0.0) | 0 | ||
| Antibiotics in past 6 mos | No | 190 | 49 (25.8) | 45 NT, 1 b, 2 e, 1 f | 0.464 |
| Yes | 149 | 44 (29.5) | 44 NT | ||
| Unknown | 3 | 1 (33.3) | 1 NT | ||
| Attends day care | No | 175 | 37 (21.1) | 35 NT, 1 b, 1 e | 0.008 |
| Yes | 166 | 57 (34.3) | 55 NT, 1 e, 1 f | ||
| Vaccination statusb | Unvaccinated | 18 | 4 (22.2) | 3 NT, 1 b | 0.222 |
| Undervaccinated | 83 | 28 (33.7) | 27 NT, 1 e | ||
| Appropriately vaccinated | 194 | 54 (27.8) | 53 NT, 1 e | ||
| Incomplete information | 47 | 8 (17.0) | 7 NT, 1 f |
a
P values for each variable were determined using Fisher's exact test.
b
A subject was considered undervaccinated for age if he or she was 6 to 15 months old and had received less than 3 doses of PRP-T or any combination of vaccine type or less than 2 doses of PRP-OMP vaccine. A subject was considered undervaccinated if older than 15 months and received less than 4 doses of PRP-T or a combination of vaccine type or less than 3 doses of PRP-OMP.