Percentage of deaths to true infections

[Mintypylonsfryingsurplus]

My maths is shocking and am struggling with post Covid brain fog too.
If know mortality/ excess deaths can be proven to be Covid how many true infections has there really been?
For example if excess deaths including definite Covid are approx 65000 in UK and those tragic deaths represent 1.4 % of infections how many cases have there been?
Apologies cant work out myself brain scrambled...

65000*100/1.4=4,642,857.

I don't think we know the percentage of cases however. It's also highly variable dependent on the age of those infected so will vary by region and by event (factory outbreak = low deaths, care home outbreak = high deaths).

1.4% of 4,642,857 gives approx 65000

Are you trying to basically work out the infection fatality rate? Because it's not 1.4% is it? It varies in studies but the highest I have seen is about 0.9%. That is average though and varies massively by age etc. For the elderly it is much higher. Much lower for the young.
The last round of antibody tests said 4 and a half million but there is reason to believe more have fought infection with T cells. Realistically though we just dont know...

Thank you for all your replies, I was trying to work out the likely minimum of total infections if the fatality rate is approx 1.4%
It would demonstrate that the number of 390000 given by the government ( tested is way too low)
Obviously regional variations etc and the fact that the UK fatality rate is higher or lower than 1.4%
It would be interesting to see this actual data.
Thank you

According to the most extensive study we currently have (Spain, 70 000 participants) the IFR is 1.1-1.5%.

Spain is surely an outlier? Even new york was 0.9%

www.google.com/amp/s/www.nytimes.com/2020/07/04/health/coronavirus-death-rate.amp.html

" On Thursday, after the World Health Organization held a two-day online meeting of 1,300 scientists from around the world, the agency’s chief scientist, Dr. Soumya Swaminathan, said the consensus for now was that the I.F.R. is about 0.6 percent"

Thanks again
So if the IFR is 0.6% that is even more infections that have occurred.
Not taking into account the spike of excess deaths above average in December 2019 so potentially a lot of people have already been infected here in the UK?

Most likely the antibody estimates are under estimates. Its impossible to tell by how much. Theres loads of reports recently on how unreliable the tests are. We don't know how many dont even produce antibodies.

CEBM (Centre for Evidence Based Medicine, Oxford Uni) suggest it's between 0.1% and 0.41%, though it will vary very widely by age; above 80, they suggest it might be 15%. So if most of your infections are in older age groups, the IFR would be greater.

www.cebm.net/covid-19/global-covid-19-case-fatality-rates/

@PatriciaHolm does that mean you cant really apply a blanket IFR to a population?

[quote Jrobhatch29]@PatriciaHolm does that mean you cant really apply a blanket IFR to a population?[/quote]
Not really, no. IFRs are very movable beasts, especially for infections that vary widely in their virility depending on age/gender/previous morbidities etc. Example using some made up stats ;-)

Say you have 1000 infections. 500 are in the over 80s, 500 in the 70-79s.
This would suggest an average IFR of ((500 x .15)+(500 x .08)) = 11.5%.

If you have 1000 infections, all in the under 50s, IFR would be more like 0.3%.

A huge difference.

It's one of the suggested reasons the US isn't (yet) seeing deaths increase to match (confirmed) infections; fatality rates for the under 50s are much much lower.

If you let CV run rampant in care homes, for example, you end up with a much higher IFR than a place that doesn't.....

The problem is always that IFR is very very hard to figure out unless you undertake a wide, randomised, long term testing strategy.

So - summary - using any back calculating from deaths to figure out infections at a population level is very very very hard.

If we had 25,000 deaths in care homes at an IFR, of, say, 10% that means 250,000 care home residents were infected, which would be 50% of residents. Around 45% of care homes had outbreaks so whilst that seems a bit high, it may not be far off.

Working out the overall population IFR from the other 25,000 deaths is much much harder....

@PatriciaHolm thank you for that. Yeah it really does depend on the ratios of the age groups infected

Thank you that makes sense, but surely everyone ( unless sheilding) has the same chance of catching it regardless of whether it becomes serious?
I am on a fb group with over 6.5 thousand long tail sufferers, many of whom never got tested in March. I just feel its more prevalent than government is letting on, i.e we contained the virus. I just thought overall excess deaths would equate to a ball park figure IFR the truer scale of infections since Feb onwards?
Although I realise certain areas or environments would produce more infection.

I think way more people have had it than antibody tests suggest but thats just my opinion

ONS has 54,023 as the excess death counts in UK thru 26 June. Not 65k.

Does that include Scotland and N Ireland or is it just for England and Wales?

ah sugar, I did write that wrong, ONS figures are E+Wales.
Still not sure where anyone got 65k from, I can't make the Scottish excess & Norn figures & E+W figures add up to 65k.

Latest excess deaths for England & wales - 58,873
www.ons.gov.uk/peoplepopulationandcommunity/birthsdeathsandmarriages/deaths/bulletins/deathsregisteredweeklyinenglandandwalesprovisional/weekending26june2020#deaths-registered-in-the-uk

Scotland - 4,917
www.nrscotland.gov.uk/news/2020/deaths-involving-covid-19-week-25-15-to-21-june

Northern Ireland - 1001
www.belfasttelegraph.co.uk/news/northern-ireland/more-than-1000-excess-deaths-in-ni-during-pandemic-39338279.html

Total = 64,791.