Contact tracing efficiency, transmission heterogeneity, and accelerating COVID-19 epidemics
Fig 2
Pathogen reproductive number, Rt, plotted against the number of cases per contact tracer calls per day, for four different numbers of contacts per case (5, 10, 20, 30; these reflect the range of contacts before and during restrictions on social gatherings [39,45,46]).
The number of contacts per case is indicated by the small numbers on each curve in the middle of the plot. The average delay between symptom onset and contact tracing (including getting tested and receiving result), 1/τIs, is set to 5 days; as a result, the green curve is identical to the green curve in Fig 1.