The Bronx is approximately 40% fully vaccinated as of June 28th, a rate of inoculation that could still allow a sizable outbreak of the delta variant. The delta outbreak would peak after about three months, with more than 28,000 cases in a single day. By comparison, an alpha epidemic would take four and half months to hit full steam, amassing about 17,100 infections during its worst day. The classic strain would barely get off the ground, with fewer than 200 daily cases after nearly six months.
This SEIR simulation assumes the Bronx is 40% fully vaccinated, and the vaccines have 90% efficacy. We ran three reproduction numbers: 2.5, 3.75 and 5.25, approximating SARS-CoV-2 classic, alpha and delta variants, respectively. We assumed no non-pharmaceutical interventions (NPIs), such as masking and social distancing, were in place.