Fig. 4
a Effect of partial curfew on the epidemic curves. Model simulations of the daily infection incidence for P1 and P2 (higher and lower socioeconomic groups respectively) before and after the partial curfew. (Overall) Simulations based on the basic reproduction numbers \( {\mathcal{R}}_{0,1}=1\cdotp 08 \) and \( {\mathcal{R}}_{0,2}=2\cdotp 36 \). (Pre-curfew) Simulations based on pre-curfew reproduction numbers \( {\mathcal{R}}_{e,1}=1\cdotp 19 \) and \( {\mathcal{R}}_{e,2}=1\cdotp 75 \). (Post-curfew) Simulations based on post-curfew reproduction numbers \( {\mathcal{R}}_{e,1}=1\cdotp 05 \) and \( {\mathcal{R}}_{e,2}=2\cdotp 89 \). Cross-transmission is modeled by using β12 = β12 = 0, 0 · 01, 0 · 02 to simulate an increase in uncontrolled transmission (or leak) from individuals in P2 to P1 and vice versa. Solid lines refer to P1 and dashed lines refer to P2. Line colors refer to different infection states: Grey = asymptomatic infections, pink = pre-symptomatic & symptomatic infections, and blue = symptomatic infections. b-c Change in the peak and overall infections of COVID-19 in P1 and P2 under different cross-transmission scenarios. From left to right, with increasing symmetric cross-transmission between P2 and P1 (i.e. β12 = β12), less and less cases are averted in P1 and the effect of the NPI on peak incidence is gradually blunted. The maximum averted COVID-19 infections in P1 is found in the absence of cross-transmission. In this case, the peak incidence is reduced by 91.4% and the total infections are averted by 21.5%. Black color refers to P1 and grey color refers to P2. (Vertical axes have been amended to highlight the differences in the effect of the intervention)