Initial Model Definitions and Formulas Used for Population Estimates
Term | Definition |
---|---|
Hosp | Calculated number of hospitalized patients (including MEDSURG and ICU) |
ICU | Calculated number of patients requiring care in the intensive care unit (including Vent and no Vent) |
Vent | Calculated number of patients in the ICU requiring mechanical ventilation |
MedSurg | Calculated number of patients requiring inpatient admission but not ICU care |
Metro | Calculated totals for the Greater New Orleans Metropolitan Area |
DC | Calculated number of patients discharged at the specified time point |
Input Variable | Definition |
R0 | Basic reproduction number (R0=3; R0=2; R0=1.5 assuming social distancing) |
β | Contacts per unit time |
γ | 1/mean recovery time = 1/(incubation + symptoms) |
t | Time, days |
St | Total susceptible at time t |
It | Total infected at time t |
New It | Newly infected at t |
Rt | Total recovered at time t |
New Rt | Newly recovered at t |
SXt | Calculated symptomatic at time t |
INCubt | Calculated incubated at time t |
Population Estimate | Formula |
Susceptible today | Stoday = Syesterday – New Itoday |
Infected today | Itoday = Iyesterday + New Itoday – New Rtoday |
Recovered today | Rtoday = Ryesterday + New Rtoday |
Symptomatic today | SXtoday = number infected 5 days prior to time today = It-5 |
Incubating today | INCubtoday = Itoday – SXtoday |
Newly infected today | New Itoday = (β * Iyesterday * Syesterday) / Sinitial |
Newly recovered today | New Rtoday = γ * Iyesterday |
New Metro Hosp | Number newly infected 5 days prior * 0.09 |
New Metro ICU | Number newly infected 5 days prior * 0.032 – New Metro Vent |
New Metro Vent | Number newly infected 5 days prior * 0.023 |
New Metro Hosp_DC | Number hospitalized 7 days prior / 7 |
New Metro ICU_DC | Number patients in ICU – no Vent 11 days prior / 11 |
New Metro Vent_DC | Number patients in ICU 14 days prior / 14 |
Total Metro Cases today | Total Metro Casesyesterday + New Metro Hosptoday + New Metro ICUtoday |
Total Metro inpatients today | Total Metro Hosptoday + Total Metro ICUtoday + Total Metro Venttoday |
Total Metro Hosp today | Total Metro Hospyesterday + New Metro Hosptoday – New Metro Hosp_DCtoday |
Total Metro ICU today | Total Metro ICUyesterday + New Metro ICUtoday + New Metro Venttoday – New Metro ICU_DCtoday – New Metro Vent_DCtoday |
Total Metro Vent today | Total Metro Ventyesterday + New Metro Venttoday – New Metro Vent_DCtoday |
Market share = 45% | MedSurgtoday = Total Hosptoday * 0.45 ICUtoday = Total ICUtoday * 0.45 Venttoday = Total Venttoday * 0.45 |