## Tuesday, March 17, 2020

### The hard facts of Covid 19 (Coronavirus)

I hope everybody is keeping safe. As I am not involved in the medical profession or politics there is little I can do other than follow the guideline that have been outlined by various health departments and help my family to do the same.

However the situation is confusing to many so last night I thought to put some of what I learned  about writing toward outlining the threat that Covid-19 (Coronavirus) represents.

Hope this helps everybody understand what we are facing.

• In a normal flu season for every individual infected 1.3 additional people get infected. Of the people who got infected less than .1% died thus giving 35,000 to 40,000 annual death in the United States due to the flu.
• The H1N1 virus circa 2009 was around 1.5 people infected for every person who came down with the virus. Fatality rate was three time higher at around .3%
• In contrast for Covid-19, for every person infected 2.2 (Jan 2020) to 2.7 (Feb 2020) additional people will get infected. Of those people who get the disease 3.5% will die.
• Different age bracket respond differently with those 70+ have been suffering a 16% fatality rate due to Covid-19
• Covid-19 numbers slightly more deadlier than to that of the 1919 Influenza virus which has an infection rate of 1.8 and a fatality rate of 2% to 3% The 1919 influenza 'Spanish Flu' had a 4% to 20% death rate. Misread the table comparing past influenza outbreak.

This based on data using standard epidemiology procedures in place for decades.

Furthermore these are fatalities, an order of magnitude (10x) more cases do not result in death but do require medical intervention and hospitalization.

In the case of the flu the annual flu shot means that actual number are far less than just multiplying the fatality rate by the population.

For my small rural town which has a population of 30,000 (city and the two surrounding townships) this means the following

• During a normal flu season (Nov to April) we can expect around 30 flu related death. The actual number will be less because of the flu shot. We can also expect 300 cases requiring hospitalization spread across those months. The actual numbers will also be less because of the flu shot.
• With Covid-19 which has no vaccine at this point, my town can expect 900 deaths probably spread across three months. More seriously we can expect 9,000 severe case requiring medical intervention like hospitalization.
• This compounded by that fact that in the case of the annual flu the onset of the disease is 1 to 4 days. For covid-19 the onset period is 3 to 14 days. A person can pass on the infection during the onset period for both.
• Moreover the fact without further measures to help the medical system handling Covid-19 cases this means all the other things like those having complication from the annual flu, trauma, infections, seizures, cancer, etc will have problem getting proper treatment thus driving up their death rate.

My town can't handle that. Nobody can handle that which is why we saw in Wuhan emergency hospitals being erected overnight.

What we can do is slow down the spread so these 9,000 cases and 900 death are spread across a longer span of time. So that those cases and the other cases get needed medical attention. And just maybe a vaccine will be developed or enough of a quarantine is place so that the cases start declining.

Be safe and I hope the above helps you make an informed decision about what you and your family needs to do.

CelticCurmudgeon said...

Thank you for the data. It helps reduce panic and fear when we know exactly what we are facing.

BrianO said...

900 deaths? Where are the citations for this information?

Robert Conley said...

It based on the reported fatality rates which currently stands at 195,892 confirmed cases and 7,865 worldwide.

For example from here
https://coronavirus.jhu.edu/map.html

or here
https://www.who.int/emergencies/diseases/novel-coronavirus-2019/situation-reports

Allen said...
This comment has been removed by the author.
Robert Conley said...

@Allen thanks for the link and comment. I found some other "worse" numbers from folks trying to estimate the final figures while reading up for my post. I opted for the conservative number as was bad enough to illustrate my point.

Allen said...

My apologies Rob, I re-posted to edit.

But we have no way of knowing if those confirmed cases will live or die. To get a better number, you would need to consider closed cases only. Closed cases meaning those who lived versus those who died. Your current number is "deaths / (those who currently have it + recovered + deaths)". It should be "deaths / (recovered + deaths)"

Even that is failing to take into account all of the people who didn't get tested...

Allen said...

And with my edit I murdered my link

James Mishler said...

Based on the numbers I've seen, in your town of 30,000, if 50% get the virus, we would be dealing with:

15,000 infected; of those, ~20% are severe cases that require bed rest at a minimum, so:

3,000 off their feet. Of these, around half require hospitalization, so:

1,500 require hospitalization.

That is, REQUIRE hospitalization. And not just any hospitalization, they require specific devices to help them breathe.

Pennsylvania has ~42,000 hospital beds, with an average of ~600 per county (some have none, some have a lot more.

There are about 50,000 respirators in the U.S., so about 1,000 per state (certainly not equally divided, but). That is an average of 15 per county in Pennsylvania.

So if your county has 1,500 cases requiring hospitalization with a respirator, and there are maybe 15 in your county... that's 1,485 deaths.

And that does not count all the dead from all the OTHER life-threatening medical issues that are not getting taken care of because the hospital is jammed with COVID-19 cases... all those folks die, too.

At the rate we are going, if not stopped, we will hit 50% infection nationwide by mid to late-April.

One month.

And because the virus damages the lungs of those who get severe cases? When it comes back around next year, barring an effective vaccine, they all die, and then there will be another round of dying and maimed, and so on, and so on, and so on.

Jeff V. said...

I hate to say this, but the numbers you published for the Spanish flu are almost certainly incorrect (e.g., if 500 million people got the Spanish flu, and 50-100 million died, then the advertised CFR of 2.5% is patently wrong -- the CFR for Spanish flu (assuming those death numbers are correct) is obviously somewhere closer to 10% to 20%! on the other hand, if we take the lower end of the claimed death rate, 50 million, and multiply it times the claimed CFR of 2.5% then there must have been a minimum of 2 billion people infected in order to reach 50 million deaths. Total world population in 1918 was about 1.8 billion people and the best guess is that only about 25% of them were infected (thus the 500 million infected people number).

In short, we have no idea what the actual CFR/R0 of Spanish flu was -- and it's been studied to death by both health experts and historians.

Similarly, of course, we lack sufficient statistical data (and even basic knowledge of the actual numbers of infected people) at this point to say ANYTHING meaningful about the CFR/R0 of COVID-19.

Sorry to quibble about this stuff, but the fact of the matter is that no one has any idea how severe (or un-severe) this virus is actually going to be at this point, and publishing this more or less amounts to spreading rumors -- something we should all strive to avoid during an actual crisis. We should all follow the guidance of the CDC and health authorities, but panicking will not help anyone through this. "Keep calm and carry on" was good advice during World War II, and it's good advice here and now.

Tom Cleaveland said...

The CDC estimates that there were 60.8 cases of H1N1 in the US between April 2009 and April 2010, with 12469 deaths. This represents a case fatality rate of 0.02%, which is a fifth of that for seasonal flu.

https://www.cdc.gov/flu/pandemic-resources/2009-h1n1-pandemic.html

Tom Cleaveland said...

Sorry--60.8 million cases of H1N1...