Covid comparison   
Based on extrapolating the New York State data of a large
(7500) sample, of the US  population of 330M, there are
roughly 10M of the population antibody positive ( 3% of
total) who have been exposed to the virus. The national hot
spot (New York State) has 15% who have been exposed. Of
the people exposed to the virus;   

10% are Symptomatic cases
2% have been hospitalized for average of 15 days.
0.8% went to ICU for average of 10 days  
0.6% die plus 0.1% who die in nursing home.

Implications are that assuming  the antibodies confer
immunity, we are still a very long way (at least 70%) away
from herd immunity. The majority of infectious people do not
know that they are, and so wander around infecting others.
Without comprehensive virus testing there is no way to
block transmission. In order to provide health care, the
number of hospital beds needs to be around 30x the daily
death count, the number of ICU beds around 12x the daily
death count.  Unfortunately, entering the ICU has a very
poor prognosis.


This analysis is based on preliminary results from an
antibody survey of New York residents found that 14.9% of
the state is positive for COVID-19 antibody. The sample size
of the survey was 7,500. This is the largest of multiple
studies that all found  a large multiple of asymptomatics.
Population of state 20M, so 3M antibody positive, 10% of
antibody positive are symptomatic, 0.7% are dying.

An update on New York state numbers shows 20 per cent of
active Covid-19 cases have been hospitalized for the virus.  
About 40 per cent of hospitalized  cases are in the ICU. At a
400 a day death rate, 5K in ICU, 12K in hospital (Ref 1)   

Nursing home residents make up almost 1 out of 5 deaths
nationwide from COVID-19 (Ref 2).

The IHME projection based on 2k daily deaths, is a need for
60k (30x or 15 days)  hospitalization beds, 20k (10x or 10
days) in the  ICU ) (Ref 3)


Is Covid just like the flu..NOT !

Covid is often compared to the flu to provide different
perspectives, what is the reality? The first graph shows 6
years of weekly flu deaths from the CDC, showing a
remarkable consistency from year to year. An average of
8000 deaths a year.  A model with a constant Ipp = 1.4
infections per person follows the repeating shape of the
infection, consistent with the literature values of  Ipp = 1-2.

The maximum in the model is created by the natural
progression of infection, which probably explains why the
pattern is repeated every year. The maximum is formed
because as more people get infected, the number of
susceptibles drops and the overall infection rate starts to
fall. This suggests that the reason that the flu stops in
summer is not heat but the fact that the flu virus runs out of
customers.


The next graph compares the 2019 flu cycle and the  Covid
infection in the US. The model of Covid used an Ipp = 5.6 (
Ref 4 )  infections per person and also  followed the  natural
disease progression (standard SIR). Initially,  the Covid
infection grew much more  rapidly  than flu, fortunately,
isolation stalled the Covid infection. The model shows what
might have happened without isolation, the death rate could
have risen to a disastrous level of more than 10,000 a day.
Even with isolation,  Covid still had a death rate 10 x worse
than the flu.

The very rapid early growth of the Covid infection is the key
evidence that  Covid is nothing like the flu, and isolation was
completely essential.

Covid is nothing like the flu !  The flu is  3x less infectious,
4x less lethal, and  reaches herd immunity in 6 months.



Ranking Covid

It is now possible to compare Covid to some well known
diseases. Covid is probably  much more infectious and  
lethal than the flu. It is as infectious as  Mumps, and more
lethal than Measles.



Ref 1 https://covidtracking.com/data/state/new-york

Ref 2 https://www.npr.org/2020/04/21/839522324/
npr-analysis-of-covid-19-deaths-at-new-york-nursing-homes

Ref 3 https://covid19.healthdata.org/united-states-of-america.

Ref 4 The R0 value is based on Covid data for the Us. It is very close
to the  median of 5.7 according to a study published online  Sanche S,
Lin YT, Xu C, Romero-Severson E, Hengartner N, Ke R. High
contagiousness and rapid spread of severe acute respiratory
syndrome coronavirus 2. Emerg Infect Dis. 2020 Jul [date cited].
https://doi.org/10.3201/eid2607.200282
Breakdown of the Covid infection based on best data in mid May.
CDC data for the flu, and a standard SIR model with a constant Ipp = 1.4 infections
person. The consistent flu cycles are caused by the natural progression of the infection.
Covid data for the US compared to CDC flu data in 2019. The model shows the
standard SIR model with constant Ipp.