Expected duration of the Corona virus threat?

[Peter Fairbrother]

On 27/02/2020 15:01, Georgi Guninski wrote:
> What is the expected duration of the Corona virus threat?

Healthwise, best guess worst case, the dying should be over in a couple 
of years. Worst guess best case, a couple of months.

> 
> Not only death counts, include fear, social, technological
> and economic threats.

Long-term consequences could be very long-term, initially ten years or 
so? Think of it like 9/11 but with a lot more dying.

> 
> And what is the mortality rate of common flu?

It varies quite a lot depending on the kind of 'flu, weather etc, but 
for seasonal 'flu about 1 in 10,000 or 0.01% per year is about average. 
A twentieth of that rate for children and the young and healthy. That's 
for everybody, including people who don't get flu.

In a year, on average, about 20% of people get 'flu. This is mainly 
because of vaccination - it would probably be about 65% without 
vaccination. The death rate for people with 'flu is about 5 in 10,000.

So say 65 million cases of 'flu in the US per year, with 30,000 US 
deaths per year, almost entirely the old - child deaths from seasonal 
flu in the US are only about 150 per year.

'Flu has been given the sobriquet "the old man's friend" - on the theory 
that it is better dying over a week from 'flu than over months or years 
from cancer, Alzheimer's, COPD etc. Gives friends and family time to say 
goodbye, but the patient doesn't suffer much or for too long. And 
seasonal 'flu kills the elderly almost exclusively.


Pandemic 'flu can kill at much higher rates - the 1918 pandemic had a 
death rate of well over 10% of the ~17% of the population who got it 
during the first six months of the pandemic, though death rates 
decreased later. This was also an all-age death spread, the 
fit-and-healthy died about as often as the elderly.




Best data I have seen for COVID-19 mortality is from 50 in 10,000 or 
0.5% for the young-and-fit to 1,500 in 10,000 or 15% for those over 75 
and those with pre-existing heart disease. Diabetes and COPD are also 
bad co-morbidities to have, at about 10% mortality.

COVID-19 seems to kill mostly the elderly, but not nearly as exclusively 
as 'flu. The young-and-fit are also very much at risk.

This would give an overall mortality rate of about 150-200 per 10,000 or 
1.5%-2%. With an estimated 65% of the US population catching COVID-19 
that would be 4 million US deaths: much worse than AIDS, and potentially 
the worst pandemic since the Plague.



What could change that? Well, that figure is for people with at least 
semi-decent health care. If society and health care break down (this is 
unlikely to happen) US mortality could reach 15 million or more. On the 
other hand extra-good healthcare might bring it down a bit.

Coronaviruses mutate fairly rapidly, and for something like 2019-nCoV 
these mutations generally tend towards less lethal varieties. So you 
might still see a lot of sick people but with a lot fewer deaths.


It is also not impossible to make a vaccine in a fairly short time - or 
make 10 vaccines, quickly test them for safety, then fuck the 
effectiveness testing and just give people the best-looking 3 or 4 safe 
ones. That could be done in about 3-4 months if lots of people were 
dying and some otherwise-sensible rules were set aside.

Antiviral drugs might also work, but ignoring licensing these are 
expensive and slow to make and of uncertain efficacy. It took quite a 
while for an effective AIDS cocktail to be worked out.


I don't have much hope that containment will stop the disease, but it is 
worth trying; if nothing else in order to slow down the spread of the 
infection. This gives more time for creating treatments and treatment 
plans, hospital preparedness, a slower case rate requires less treatment 
capacity and allows more treatment per patient, and so on.


People might (!would!) argue the numbers in this post a little, but I 
think they are at least roughly correct. The COVID-19 numbers might be a 
bit low as it is in many cases still too early to predict the outcome.

Peter Fairbrother