Can someone explain to me ( or point me in the right direction ) If 1 in 60 people have covid ( according to the media ) and we have had this for nearly 2 years now why hasn't the whole population had it at least twice
Ta
M
Can someone explain to me ( or point me in the right direction ) If 1 in 60 people have covid ( according to the media ) and we have had this for nearly 2 years now why hasn't the whole population had it at least twice
Ta
M
Look at the ONS infection survey and look in tab 1d, of the data spreadsheet.
This has the estimated infection rate for non-overlapping 2 week periods starting 26/4/2020. Add them all up and it comes to about 33.5%.
There were many periods, where the infection rate was much lower than now.
Whenever a new infectious agent comes along not everyone gets it. Either initially or during some specific time scale. Say 5 to 10 years. Or even over a lifetime.
The At Risk Population is tern used to quantify who is at risk of getting the infection. During the initial waves or during later general endemic spread. For new serious variants of influenza, like H1N1 Swine Flu back in 2009, the initial At Risk Population population was the usual one for low infectiousness viral respiratory infections. About 40%. The At Risk Population for endemic spread in the following decade was about 60%. Which is how it played out.
There is always some group who will have high cross immunity to the new infectious agent. For H1N1 in 2009 - 2012 (the first big wave) it was people over the age of 60. Due to prior pandemic flu exposure in 1958.
For SARs CoV 2 due to the very high cross immunity among human corona virus infections (HCOV) was always going to have a much lower attack rate than pandemic influenza. Which is how it played out. Children and young people have very high endemic human corona virus infection rates, > 10% for children, > 1% for young adults. So the At Risk Population initially was going to be around 20% with maybe endemic At Risk Population of around 40%. With up a 60% lifetime infection rate depending on how long infection immunity lasted. With those under 50 mostly having asymptotic or mild symptoms.
So from the very beginning only a minority was going to actual get an infection and for most, like me, it was just like a very weird flu. At least for me very mild compered to Swine flu in 2009 which took months to recover from but the pain in the olfactory nerves with SARS CoV 2 was quite intense at times.
The only people at actual high health risk from SARs CoV 2 were those already at high risk from pneumonia. Those with a very high PSI/PORT score. Which is why overall morality rates did not shifted much over the last two years. Most FROM deaths were people dying of one pneumonia rather than another. Substitute cause deaths rather than novel cause deaths.
That wasn't really what I was on about. Maybe it's me being a bit simplistic but if 1 in 60 have the virus in any particular week and the virus lasts about 10 days - lets just say 2 weeks and ignore that not everyone gets it at the same time. Then in a month 1 in 30 have had it. Assuming that very few people get it twice then in 30 months everyone will have had it and since we are about 2 years into this there can't be many people left that haven't had it by now
@interele there are some who have not had it, most of those who were vaccinated in time have not had it, and those able to repel it, but I agree the reason for the present period of flat cases may be down to immunity levels being high enough to prevent large spike in cases.
we are presently in a rapidly oscilating period of small cycles/waves
The key thing is that for many periods the morning infection rate was quite low.
It would have required 2% infection rate for 50 non-overlapping 2 week periods to get the whole population. That is 100 weeks. Neither has happened, so there is still some remaining population to work through.
it's not exactly flat but the spikelets are getting smaller and smaller. We have had 4 mini waves in a short period, should we assume the spike will trend to a flat line soon, where cases are almost constant, i.e. a pattern of catch it , recover, get susciptible over a while, catch it again.... that might be the pattern.
in the last few waves in the plot, are we watching a harmonic damper with a wave length of 50 days?
in the last few waves in the plot, are we watching a harmonic damper with a wave length of 50 days?
If it not doing as I think, it's doing a damned good impression of a harmonic oscilation with wavelength a bit less than 50 days. If it acts as I suspect, we should see a low 50 days after Nov 8, which is two days after boxing day. It's taking 2 or 3 weeks from low to high, 21 days, there was a low on nov 8 so the next spikelet should be on dec 8, then it should decline all the way to Christmas, of course all this ignore the Omicron strain. That could spoil the nice pattern as well as Christmas.of course this could be total rubbish. only time will tell,
