Volume 20, Number 7—July 2014
Research
Changes in Capsule and Drug Resistance of Pneumococci after Introduction of PCV7, Japan, 2010–2013
Table 1
Vaccine and nonvaccine serotypes of Streptococcus pneumoniae in children after introduction of PCV7, Japan, April 2010–March 2013*
Age group, y, and serotype | Isolates, no. (%) |
p value | ||
---|---|---|---|---|
2010, n = 300† | 2011, n = 146‡ | 2012, n = 156§ | ||
<1 | <0.001 | |||
VT | 51 (17.0)‡ | 26 (17.8) | 3 (1.9) | |
NVT |
19 (6.3) |
14 (9.6) |
25 (16.0) |
|
1 | <0.001 | |||
VT | 103 (34.3) | 25 (17.1) | 9 (5.8) | |
NVT |
31 (10.3) |
28 (19.2) |
62 (39.7) |
|
2–4 | <0.001 | |||
VT | 55 (18.3) | 23 (15.8) | 6 (3.8) | |
NVT |
19 (6.3) |
14 (9.6) |
39 (25.0) |
|
>5 | 0.733 | |||
VT | 11 (3.7) | 6 (4.1) | 5 (3.2) | |
NVT |
11 (3.7) |
10 (6.8) |
7 (4.5) |
|
Total | <0.001 | |||
VT | 220 (73.3) | 80 (54.8) | 23 (14.7) | |
NVT | 80 (26.7) | 66 (45.2) | 133 (85.3) |
*PCV7, 7-valent pneumococcal conjugate vaccine; VT, vaccine serotype (serotypes 4, 6B, 9V, 14, 18C, 19F, 23F); NVT, serotypes not included in PCV7.
†Voluntary vaccination with PCV7.
‡Implementation of Urgent Promotion of Vaccination incentive.
§Just before the introduction of 13-valent PCV.