Table 2.

Incidence Rates of Invasive Pneumococcal Disease by Serotype Category—Before and After Introduction of 13-Valent Pneumococcal Conjugate Vaccine at Kaiser Permanente Northern California

	Incidencea (per 100 000)
	PCV7 Period	PCV13 Period	Rate Ratio (PCV13 Period/PCV7 Period)	95% Confidence Interval
Serotype Category	May 2008–April 2010	May 2011–April 2018
≥6 wk to <6 y
All IPD	11.57	4.09	0.35	0.25–0.50
PCV13b	5.12	0.84	0.16	0.09–0.30
PCV7c	N/A	0.10	N/A	0.08–N/A
Cross-reactived	0.19	0.79	4.15	0.74–88.17
PPSV23e	5.50	1.89	0.34	0.21–0.56
Non-PCV13f	1.71	2.52	1.47	0.75–3.19
NAS	4.74	0.73	0.15	0.08–0.30
≥6 wk
All IPD	9.49	6.23	0.66	0.60–0.72
PCV13b	4.67	1.89	0.40	0.35–0.46
PCV7c	0.24	0.23	0.94	0.56–1.66
Cross-reactived	0.96	1.01	1.06	0.81–1.39
PPSV23e	5.99	3.16	0.53	0.47–0.59
Non-PCV13f	3.34	3.35	1.00	0.87–1.16
NAS	1.48	0.99	0.67	0.54–0.85

All IPD cases, regardless of membership and whether serotyped, were included. Membership refers to patients who were members of Kaiser Permanente Northern California (KPNC) for at least 2 months in each year. An IPD case was a unique case separated by a period of 14 days. Year of PCV13 introduction at KPNC (May 2010–April 2011) not shown.

Abbreviations: IPD, invasive pneumococcal disease; N/A, not applicable; NAS, not available for serotyping or untypeable; PCV, pneumococcal conjugate vaccine (7 or 13 valent); PPSV23, pneumococcal polysaccharide vaccine (23 valent).

^aAnnual incidence of IPD = (IPD cases)/(membership/100 000).

^bPCV13 serotypes include 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, 23F.

^cPCV7 serotypes include 4, 6B, 9V, 14, 18C, 19F, 23F.

^dCross-reactive serotypes include 6C, 7A, 7C, 9L, 9N, 19C, 23A, 23B.

^ePPSV23 serotypes include 1, 2, 3, 4, 5, 6B, 7F, 8, 9N, 9V, 10A, 11A, 12F, 14, 15B, 17F, 18C, 19A, 19F, 20, 22F, 23F, 33F.

^fAll serotypes not included in PCV13.