Fig. 3.

Impact of delays in contact tracing on new COVID-19 infections and deaths. Difference-in-differences regression estimates (at level of LTLA) for the average effect of each case referred to contact tracing with a delay of between 6 and 14 d on new infections per capita and new COVID-19 deaths per capita in the 6 wk period following the Excel error. All regressions control for area fixed effects and date fixed effects, along with nonlinear local time trends in pretreatment infection intensity as well as nonlinear trends in a host of over 50 area characteristics. Complete regression results are reported in SI Appendix, Table S2; 90% CIs are displayed.