Volume 10, Number 9—September 2004
Research
Space-Time Cluster Analysis of Invasive Meningococcal Disease
Christian J.P.A. Hoebe*
, Hester de Melker†, Lodewijk Spanjaard‡, Jacob Dankert‡1, and Nico Nagelkerke†
, Hester de Melker†, Lodewijk Spanjaard‡, Jacob Dankert‡1, and Nico Nagelkerke†Table 2
Clustering of meningococcal disease cases by serosubtype (serogroup, serotype, and subtype)a,b
| Serosubtypes (phenotype) | Field clustersc | Cases/cluster | % excess probability | 95% CI | n |
|---|---|---|---|---|---|
| B:1:P1.4 | 1 Primary school | 3 | 12.0 | 4.2%–19.7% | 87 |
| B:1:P1.14 | 1 Swimming pool | 4 | 7.2 | NS (–8.0% to 22.4%) | 25 |
| B:1:P1.16 | 1 Primary school | 3 | 10.0 | 2.4%–17.6% | 92 |
| 1 Daycare center | 2 | ||||
| 1 Household | 2 | ||||
| B:4:P1.2,5 | 1 Household | 2 | 1.9 | NS (–3.8% to 7.7%) | 52 |
| B:4:P1.4 | 2 Primary schools | 3 and 5 | 2.0 | NS (–0.7% to 4.6%) | 1,376 |
| 4 Primary schools | 2 | ||||
| 2 Daycare centers | 2 and 3 | ||||
| 6 Households | 2 | ||||
| B:4:P1.5 | 1 Daycare center | 2 | 20.0 | 3.2%–36.9% | 25 |
| B:4:P1.7 | NFC | 6.4 | NS (–2.7% to 15.5%) | 47 | |
| B:4:P1.9 | 1 Primary school | 3 | 7.2 | NS (–8.0% to 22.4%) | 36 |
| B:4:P1.10 | 1 Household | 2 | 4.8 | 0.1%–9.5% | 205 |
| B:4:P1.14 | NFC | 5.9 | NS (–2.5% to 14.2%) | 34 | |
| B:4:P1.15 | NFC | 4.0 | NS (–0.4% to 8.4%) | 129 | |
| B:4:P1.16 | 1 Household | 2 | 2.2 | NS (–2.4% to 6.8%) | 63 |
| B:4:P1.NT | 1 Primary school | 2 | 2.6 | NS (–0.8% to 6.1%) | 455 |
| 1 Daycare center | 2 | ||||
| 1 Household | 3 | ||||
| B:NT:P1.14 | 2 Households | 2 and 3 | 13.0 | NS (–1.9% to 27.9%) | 23 |
| B:NT:P1.15 | 1 Household | 2 | 7.2 | NS (–1.7% to 16.0%) | 39 |
| B:NT:P1.16 | 1 Household | 2 | 10.0 | NS (–4.4% to 24.4%) | 20 |
| B:NT:P1.NT | 1 Household | 2 | 10.7 | 4.7%–16.8% | 123 |
| B:14:P1.4 | 1 Daycare center | 2 | 0.9 | NS (1.4% to 12.2%) | 85 |
| 1 Household | 2 | ||||
| B:15:P1.7 | NFC | 11.3 | 0.1%–22.6% | 53 | |
| B:15:P1.7,16 | 1 Primary school | 2 | 6.8 | 1.4%–12.2% | 109 |
| B:15:P1.9 | 1 Household | 2 | 10 | NS (–1.4% to 21.4%) | 30 |
| B:16:P1.14 | 1 Household | 2 | — d | 10 | |
| B:16:P1.2,5 | 1 Daycare center | 3 | 13.6 | NS (–1.9% to 29.2%) | 22 |
| C:2a:P1.2,5 | 1 Household | 2 | –1.0 | NS (–5.4% to 3.4%) | 164 |
| C:NT:P1.5 | NFC | 10 | NS (–4.4% to 24.4%) | 20 | |
| C:14:P1.12 | 1 Household | 2 | — d | 2 |
aThe following results are shown: serosubtypes with reported field clusters, serosubtypes with significant excess probability for clustering by nearest-neighbor analysis, and serosubtypes with nonsignificant excess probability of more than 3% (bold percentages significant).
bCI, confidence interval; NT, not typable; NS, not significant.
cNFC, no field cluster was reported for this serotype.
dCalculating excess probability not possible because n is too small.
