Volume 6, Number 4—August 2000
Research
Reemergence of Pertussis in the Highly Vaccinated Population of The Netherlands: Observations on Surveillance Data
Table 2
1- to 4- yr-olds | Vaccine efficacy | 5- to 9- yr-olds | Vaccine efficacy | ||
---|---|---|---|---|---|
Year | Method of diagnosis | (N) | (%)a | (N) | (%)a |
1993 | Microbiologic | 14 | 93 | 14 | 94 |
2-point serology | 25 | 91 | 28 | 75 | |
1-point serology | 24 | 79 | 26 | 50 | |
Otherb | 35 | 96 | 20 | 90 | |
Total | 98 | 93 | 88 | 84 | |
1994 | Microbiologic | 23 | 56 | 15 | 42 |
2-point serology | 36 | 67 | 36 | 83 | |
1-point serology | 63 | 71 | 65 | c | |
Otherb | 37 | 89 | 29 | 91 | |
Total | 159 | 77 | 145 | 72 | |
1995 | Microbiologic | 14 | 85 | 9 | 67 |
2-point serology | 27 | 82 | 19 | 64 | |
1-point serology | 39 | 64 | 45 | c | |
Otherb | 37 | 53 | 27 | 67 | |
Total | 117 | 72 | 100 | 45 | |
1996 | Microbiologic | 116 | 67 | 123 | 3 |
2-point serology | 245 | c | 288 | 49 | |
1-point serology | 545 | c | 782 | c | |
Otherb | 290 | 66 | 355 | 40 | |
Total | 1196 | 34 | 1548 | 16 | |
1997 | Microbiologic | 63 | 51 | 68 | 57 |
2-point serology | 110 | c | 131 | c | |
1-point serology | 283 | c | 345 | c | |
Otherb | 244 | c | 260 | c | |
Total | 700 | c | 804 | c |
aEstimated vaccine effectiveness; a vaccine-coverage of 96% was used to estimate the incidence and vaccine effectiveness.
bEpidemiologic, serologic (differentiation between positive two-point serology and positive one-point serology not possible), clinical or method of diagnosis unknown.
c Vaccine effectiveness could not be estimated as the percentage vaccinated was more than 96%.
1Vaccine effectiveness = 1 – (proportion of vaccinated cases/1 – proportion of vaccinated cases) X (1 – proportion vaccinated in the population/proportion vaccinated in the population).
Page created: December 16, 2010
Page updated: December 16, 2010
Page reviewed: December 16, 2010
The conclusions, findings, and opinions expressed by authors contributing to this journal do not necessarily reflect the official position of the U.S. Department of Health and Human Services, the Public Health Service, the Centers for Disease Control and Prevention, or the authors' affiliated institutions. Use of trade names is for identification only and does not imply endorsement by any of the groups named above.