The SARS-CoV-2 epidemic outbreak: a review of plausible scenarios of containment and mitigation for Mexico

Manuel Adrian Acuna-Zegarra; Andreu Comas-Garcia; Esteban Hernandez-Vargas; Mario Santana-Cibrian; Jorge X. Velasco-Hernandez

In our third case we explore variation in the time to start the isolation. Here the time to reduce the contact rates is θ = 7 days and the target reduction is 60%. The initial dates of isolation are: March 23rd (blue line), March 30th (red line) and April 6th (black line). The objective of this scenario is to asses what would happen if large cities start isolation and enforce behavioral change several days after this was done in the Mexican capital. Figure 18(a) shows the increase in incidence as the isolation start date increases. Solid lines represent the situation before isolation and the dashed lines represent the situation after the start of isolation. Figure 18(b) shows that if the onset of isolation had occurred one or two weeks after March 23rd, then by week 16, the cumulative incidence would increase by 12 058 and 45 118 new cases, respectively. This scenario underlines the importance of taking contingency measures with due anticipation, otherwise the number of infected people will notoriously increase. Figure 18 : (a) Incidence and (b) cumulative incidence for the isolated environment. Here we consider that the reduction of contact rate reduction is 60%, and the time it takes to get the contact rate reduction is equal to 7. Blue, red and black lines mean that the dates for start de isolation are 31, 38 and 45 days after the first arrival of an infected individual to Mexico City, respectively. Horizontal axis is time in days and the vertical axis is number of individuals.