Volume 17, Number 4—April 2011
Research
Carriage of Streptococcus pneumoniae 3 Years after Start of Vaccination Program, the Netherlands
Table 2
Frequencies of nasopharyngeal carriage of Streptococcus pneumoniae in children and their parents before and 3 years after implementation of PCV7 vaccination program, the Netherlands*
Participant s | Pre-PCV7, no. (%) | Post-PCV7, no. (%)† | OR‡ (95% CI) | aOR§ (95% CI) |
---|---|---|---|---|
11-mo-old children | n = 319 | n = 329 | ||
PCV7 | 122 (38) | 25 (8) | 0.13 (0.08–0.21) | 0.14 (0.09–0.23) |
Non-PCV7 | 92 (29) | 129 (39) | 1.59 (1.15–2.21) | 1.64 (1.15–2.32) |
All |
214 (67) |
154 (47) |
0.43 (0.31–0.59) |
0.44 (0.31–0.63) |
24-mo-old children | n = 321 | n = 330 | ||
PCV7 | 114 (36) | 14 (4) | 0.08 (0.05–0.14) | 0.08 (0.05–0.15) |
Non-PCV7 | 97 (30) | 148 (45) | 1.88 (1.36–2.59) | 2.01 (1.43–2.84) |
All |
211 (66) |
162 (49) |
0.50 (0.37–0.69) |
0.51 (0.36–0.72) |
Parents | n = 296 | n = 324 | ||
PCV7 | 25 (8) | 2 (1) | 0.07 (0.02–0.29) | 0.06 (0.01–0.26) |
Non-PCV7 | 25 (8) | 49 (15) | 1.93 (1.16–3.22) | 1.98 (1.16–3.37) |
All | 50 (17) | 51 (16) | 0.92 (0.60–1.41) | 0.90 (0.57–1.40) |
*PCV7, all serotypes included in 7-valent pneumococcal conjugate vaccine; OR, odds ratio; CI, confidence interval; aOR; adjusted odds ratio; non-PCV7, all other serotypes not included in 7-valent pneumococcal conjugate vaccine; all; all pneumococcal serotypes.
†325/329 (99%) swabs are taken just before the booster vaccination at 11 mo of age and 4/329 (1%) children had received a booster vaccination within 1 week before the sample was obtained.
‡All ORs are based on comparison with pre-PCV7 control cohort.
§For children, ORs were adjusted by multivariate analysis for sex, month of sampling, presence of siblings in the household, day care attendance, passive smoke exposure indoors, symptoms of a respiratory tract infection during sampling, and antimicrobial drug use within 1 mo before the sample was taken. For parents, ORs were adjusted for sex, months of sampling, antimicrobial drug use within 1 month before the sample was taken, and active smoking.