Fig. 8

Positivity rates over time for contact tracing interventions. Results shown are based on R_S = 1.95 and R_A = 0.8 (reproduction numbers for the SARS-CoV-2 variant with 56% higher transmissibility with respect to the wild-type SARS-CoV-2 variant). The positivity rate is computed by the percentage of positive tested contacts among all traced contacts using data of all 100 simulation runs merged. Positivity rates are assigned to the day of symptom onset of the index case, i.e., HCW that developed symptoms due to a SARS-CoV-2 infection. Traced contacts who developed symptoms due to a SARS-CoV-2 infection are excluded from contact tracing as we assume that they are always correctly identified. The plot shows the 7-day moving average (coloured line) and the 95% Bayesian beta-binomial confidence interval (shaded area). A Tracing contacts of symptomatically infected HCWs of the last 2 days before symptom onset using a diagnostic test with perfect test sensitivity. B Tracing contacts of symptomatically infected HCWs of the last 2 days before symptom onset with testing 5 days after contact with the index case assuming time-varying test sensitivity. C Tracing contacts of symptomatically infected HCWs of the last 7 days before symptom onset with testing 5 days after contact with the index case assuming time-varying test sensitivity