The delta variant would hit an unvaccinated Bronx harder and faster than the alpha variant, first identified in the U.K., or the original strain of the SARS-CoV-2 coronavirus. The delta outbreak would peak after about two months, with more than 67,000 cases in a single day. By comparison, an alpha epidemic would take three months to hit full steam, amassing about 47,000 infections during its worst day. The classic strain is way behind, summiting with 26,000 cases at around four and half months
This SEIR simulation assumes the Bronx has a fully susceptible population. We ran three reproduction numbers: 2.5, 3.75, and 5.25, approximating SARS-CoV-2 classic, the alpha variant and delta variant, respectively. We assumed no non-pharmaceutical interventions (NPIs), such as masking and social distancing, were in place.