Editorial

COVID Models to Know Future Numbers (For attention of Doctors)

Case fatality rate:Number of deaths/number of cases, As on 5 pm 23rd March, 14924/345289 = 4.32 % Correct formula: CFR = deaths at day.x /cases at day.x-(T), (where T = average time period from case confirmation to death, which is 14 days)

Deaths on 23rd March = 14924; Cases 14 days before 10th March = 114381

Correct CFR = 14924/114381= 13%

Deaths in symptomatic cases= 1-2%, Number of deaths X 100= expected number of symptomatic cases Symptomatic casesx 50 =number of asymptomatic cases Total expected number of cases: Italy scenario: 978/million population (0.1% of the population), China scenario: 56/million population, Switzerland scenario: 1000/million population, Average scenario 46 per million population, Average scenario India: 50 per million population Expected Number of cases after seven days

Number of cases today x 2 (doubling time 7 days, normal spreader)

Number of cases x 6 (Doubling time 2 days, super spreader)

Number of cases expected in the community:We can look at the number of deaths occurring in a five-day period, and estimate the number of infections required to cause these deaths based on a 3.3% fatality rate.

We can then compare that to the number of new cases detected in the five-day period 17 days earlier to estimate the proportion of actual cases that were detected 17 days ago.

This will give us an estimate of the total number of cases, both confirmed and unconfirmed.

Lock down effect = reduction in cases after average incubation period (5 days)

Lock down effect in reduction in deaths: on day 14 (time to death) Requirements of ventilators on day 9: 3% of number of new cases detected Requirement of future oxygen on day 7: 15% of total cases detected today Number of people which can be managed at home care: 80% of number of cases today; Requirements of ventilators: 3% of number of cases today Requirement of oxygen beds today:15% of total cases today

Dr KK Aggarwal

President CMAAO, HCFI and Past National President IMA