Bulletin of the World Health Organization

Sentinel versus population-based surveillance of pneumococcal conjugate vaccine effectiveness

Lee M Hampton, Elizabeth R Zell, Stephanie Schrag & Adam L Cohen

Volume 90, Number 8, August 2012, 568-577

Table 2. Children aged under 5 years hospitalized with invasive pneumococcal disease (IPD), United States of America, 1998–1999 and 2006a

S. pneumoniae serotype and surveillance areab Annual average 1998–1999
 2006a
 Change in incidence
No. of cases Incidencec No. of cases Incidencec % 95% confidence intervalc
All serotypes
California 7 20.4 3 7.3 −64 −90 to 25
Connecticut 55 25.4 23 11.3 −55 −72 to −30
Georgia 90 31.0 37 9.6 −69 −78 to −56
Maryland 56 34.3 36 21.5 −37 −57 to −9
Minnesota 81 44.9 27 13.7 −69 −80 to −54
New York 16 20.5 8 12.7 −38 −71 to 34
Oregon 16 16.6 6 5.7 −66 −86 to −18
Tennessee 39 44.0 8 8.0 −82 −91 to −62
All 360 31.4 148 11.7 −63 −69 to −55
Serotypes in PCV7d
California 6 16.0 0 0.0 −100 NA
Connecticut 45 21.0 1 0.5 −98 −100 to −83
Georgia 72 24.8 1 0.3 −99 −100 to −93
Maryland 49 29.7 2 1.2 −96 −99 to −84
Minnesota 62 34.1 0 0.0 −100 NA
New York 13 16.7 0 0.0 −100 NA
Oregon 13 13.9 0 0.0 −100 NA
Tennessee 33 37.1 0 0.0 −100 NA
All 293 25.5 4 0.3 −99 −100 to −97
Serotypes not in PCV7d
California 2 4.4 3 7.3 68 −66 to 733
Connecticut 10 4.4 22 10.8 145 33 to 353
Georgia 18 6.2 36 9.3 50 −6 to 138
Maryland 8 4.6 34 20.3 342 141 to 712
Minnesota 20 10.8 27 13.7 27 −22 to 108
New York 3 3.8 8 12.7 230 15 to 851
Oregon 3 2.7 6 5.7 113 −35 to 597
Tennessee 6 6.9 8 8.0 17 −52 to 187
All 70 5.9 144 11.4 93 53 to 144

NA, not applicable; PCV7, seven-valent pneumococcal conjugate vaccine.

a PCV7 was introduced in the United States in 2000.

b Areas covered by the Active Bacterial Core surveillance system.

c Cases per 100 000 population.

d PCV7 includes Streptococcus pneumoniae serotypes 4, 6B, 9V, 14, 18C, 19F and 23F.