Table S1.

Parameter estimates when analysis uses the 681 cases detected by passive and active surveillance (baseline) and when it is restricted to the 495 cases detected by passive surveillance

VariableSummary statistic681 cases from passive-plus-active surveillance (baseline)495 cases from passive surveillance
Serial intervalMean6.8 (6.0, 7.8)7.6 (6.4, 9.0)
SD4.1 (3.4, 5.0)4.8 (3.8, 6.1)
Reproduction numbers
 Within clusterInitial mean RC0.45 (0.33, 0.58)0.36 (0.24, 0.51)
Initial SD σC0.53 (0.35, 0.78)0.55 (0.33, 0.90)
Probability it starts >112% (6%, 18%)10% (4%, 16%)
Value after 10 cases (relative to starting value)47% (34%, 63%)46% (32%, 68%)
 Within regionRR0.24 (0.19, 0.29)0.22 (0.17, 0.29)
 Between regionRO0.05 (0.02, 0.09)0.04 (0.004, 0.09)
Risk of introduction from reservoir
Nb at start of study period (weekly)0.5 (0.2, 0.8)0.4 (0.2, 0.7)
Nb at end of study period (weekly)2.1 (1.0, 3.6)2.4 (1.2, 3.9)
Exponential growth rate α (daily)0.003 (0.001, 0.005)0.003 (0.001, 0.005)
Source of infection, %
Within cluster60% (57%, 63%)57% (54%, 60%)
Within region23% (20%, 27%)22% (18%; 26%)
Between region5% (2%, 8%)4% (0.4%, 8%)
Reservoir12% (9%, 15%)17% (13%, 20%)