Figure 1.

Model and impact of contact tracing on the epidemic size. (a) Schematic illustration of the investigated epidemic model. (b) Relative reduction in the average epidemic size as a function of MCT probability p_ct and app adoption rate p_app, with respect to the situation of only case isolation, with p_md = 0.5, for OD, with θ_ct = θ_app = 15 min. Here ${\tau }_{\mathrm{ct}}=2\hspace{0.17em}\mathrm{days}$, τ_dct = 0. (c) The same for SD (threshold θ_ct = θ_app = 15 min). (d) Same as (c), for three slices: along the p_ct axis with p_app = 0, along the p_app axis with p_ct = 0 and along the diagonal p_ct = p_app. (e) Relative reduction as a function of the testing and diagnosis rate of mildly symptomatic p_md, for the SD with various values of p_ct = p_app.