Skip to main content

Table 3 Acquisition and clearance of Streptococcus pneumoniae carriage in 3 day-care centres in Finland, 2001–2002

From: Comparative analysis of Streptococcus pneumoniaetransmission in Portuguese and Finnish day-care centres

  Clearance Acquisition in non-carrying children Acquisition in carrying children
Target serotype Exposure1 Events Person-time2 Events Person-time3 Events Person-time4
9V Yes 7 12 7 56 1 14
No 3 3 6 300 1 83
18C Yes 7 16 9 87 0 11
No 4 4 1 269 0 81
3 Yes 1 3 6 105 1 30
No 8 11 4 251 0 68
15BC Yes 1 4 1 77 0 19
No 5 12 7 279 0 77
19A Yes 4 5 0 35 0 8
No 3 3 2 321 0 96
19F Yes 2 3 1 28 1 8
No 2 8 2 328 1 93
11A Yes 2 2 0 18 0 8
No 0 4 1 338 5 98
14 Yes 0 0 0 12 0 5
No 3 4 2 344 1 103
35F Yes 0 1 1 40 0 13
No 1 3 1 316 2 95
38 Yes 0 0 0 24 0 13
No 2 3 2 332 0 96
22 Yes 0 0 0 20 0 0
No 1 5 0 336 2 107
33 Yes 0 0 0 0 0 0
No 0 0 2 356 0 112
6A Yes 0 0 0 8 0 6
No 1 1 1 348 0 105
6B Yes 0 0 0 12 0 7
No 1 2 1 344 0 103
7 Yes 0 0 0 9 0 1
No 1 1 1 347 0 110
10 Yes 0 0 0 4 0 2
No 1 1 0 352 0 109
18B Yes 0 0 0 3 0 1
No 1 1 0 353 0 110
35B Yes 0 0 0 0 0 0
No 0 0 1 356 0 112
9N Yes 0 0 0 0 0 0
No 0 0 1 356 0 112
165 Yes 0 0 0 7 0 4
No 0 0 0 349 0 108
Total: Yes 24 46 25 545 3 150
No 37 66 35 6575 12 1978
61 112 60 7120 15 2128
  1. The crude estimates of the model parameters are (cf. Appendix): the transmission rate β ^ = 25 κ ^ × 545 / 85.26 = 0.26 (per month); the community acquisition rate per serotype (in non-carrying children) κ ^ = 35 / 6575 = 0.005 (per month); the clearance rate of carriage μ ^ = 61 / 112 = 0.54 (per month); the competition parameter φ ^ = 12 / 1978 / 35 / 6575 = 1.14 . For parameter β, the denominator (85.26) is not directly readable from the data as presented in the table. Only samples from two consecutive visits were considered (85% of the scheduled pairs of consecutive visits).
  2. 1 Exposure is here defined as the presence of at least one carrier of the target serotype in the other attendees in the room.
  3. 2 Person-time here is the total time, in months, spent carrying pneumococcus overall (total row) or a specific serotype (serotype rows) stratified by the presence or absence of other carriers of the specific serotype.
  4. 3 Person-time here is the total time, in months, spent as a non-carrier, stratified by exposure to the specific serotype. For the total row, the time is a sum of serotype-specific person-times.
  5. 4 As in 2 but for children carrying pneumococcus.
  6. 5 Sampled only once in a child which was missing at the next visit.