Yesterday I wrote about the latest Public Health England (PHE) report claiming that the Delta (Indian) variant is much more infectious than the Alpha (British) variant. I noted that the main measure of transmissibility – the secondary attack rate (i.e., the proportion of contacts that an infected person infects) – has varied over time.
It occurred to me that it would be useful to plot these attack rate values to show them graphically. So I went through the 15 technical briefings released by PHE so far and extracted the secondary attack data for the three variants (Wuhan, Alpha, Delta) and plotted them in the graph above.
There are a few points worth making from this about the infectiousness of the Covid variants.
First, between 85% and 92% of the contacts of all those infected with any of the COVID-19 variants do not get infected. This is an indication of the high level of immunity (i.e., low level of susceptibility) in the population and the low absolute infectiousness of the virus.
Second, new variants appear to start off with – or quickly acquire – a high attack rate compared to established variants, a rate which then declines. The decline for the Alpha variant occurred prior to any significant vaccine coverage meaning it cannot all be attributed to the vaccines. Conversely, despite the high vaccine coverage in April and May the Delta attack rate spiked. Nonetheless, it has already sharply declined. (The reason for the sudden drop in the Alpha attack rate from 10% to 8% at the end of April is unclear.)
Third, the Alpha variant was once more transmissible than the Delta variant at its recent peak, but is now much less transmissible.
While more data from more variants would help to confirm the patterns here, the data so far suggest that new variants will often be more infectious than established variants to begin with, but this will not last. Further, the degree of infectiousness appears to arise more from factors such as the epidemic phase or the season than inherent properties of the variant, save insofar as the new variant is slightly better at evading our immune defences for a time. And I mean slightly. Only 3% more contacts of those infected with the Delta variant are being infected compared to the Alpha variant, a difference that is dropping week on week.
The upshot is we should stop being frightened by claims that the latest new variant is “50% more infectious”, which are a distraction, and focus on levels of serious disease and how best to cope with them.
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“Hyper-transmissible variant claims nonsense”. So that’s that then We can therefore look forward to the announcement of a full return to normality from the 21st on Monday. Can’t we?
Even official figures for “Covid” deaths (still overstated) for the last three weeks are 59, 61 and 60. Any delay on Monday, so far as I’m concerned, means they are putting an agenda before people’s lives.
Did you ever doubt that?
Neat bit of work, Will (burning the midnight oil, I see). If only the tyrants would pay attention.
The immediate question regarding the delta variant is that its transmissibility was higher a month ago and is going down. If this is an important parameter (bearing in mind high immunity now anyway), there is no reason to postpone lockdown.
Absolutely. I think the work Will has been doing, particularly over the last month or so, has been brilliant.
The problem isn’t the ‘tyrants’ not paying attention Mike, it’s the majority of the so-called adult population.
I hate repeating myself but…
The pandemic is OVER. We have had two waves.
The virus IS mutating – towards a common cold virus that will be a nothing burger in future.
Putting evolutionary pressure on the virus is stupidity. I know Mike Yeadon disagrees with Geert VB but I think they are talking at cross-purposes: Mike is stating that the current mutations are 0.3% different, whereas Geert is saying (now joined by Montagnier) that we COULD create some seriously nasty new variant with what we are doing.
I wish they would sit down and have a discussion – as science is supposed to be done. Sparks may fly, but I think Geert is a reasonable man (I already know Mike is, having watched dozens of his interviews).
The Darkhorse Podcast with Brett Weinstein and Geert was fascinating, as Brett is an incredible teacher and scientist. I highly recommend you watch this: https://www.youtube.com/watch?v=BNyAovuUxro
The bottom line is, these are leaky “vaccines”. They do not prevent transmission or infection. Since they only reduce symptoms (like Ivermectin + Vitamin D + Zinc + Budosonide, but with downsides) they are not vaccines. It’s possible that someone could have a really nasty strain inside them and they turn into a “Typhoid Mary” super-spreader.
I don’t believe that a Marek’s Disease scenario is likely, since we don’t live in battery cages like chickens (yet, I’m sure Klaus would like that). But I do think this is worthy of considering.
‘It’ never reached ‘pandemic’ status, and ‘it’ was over by June 2020 once the care home debacle ended.
‘It’ creates transmissionable infections for somewhere in the 8-15% of the population , the vast majority of those never really know they have had it, a fraction of that number get ill, a fraction of that number need hospitalisation and a fraction of that number die; almost all elderly with comorbidities.
‘It’ is just an excuse for societal transformation which employs injections of an experimental gene therapy and subsequent biotech IDs for use in a totalitarian society.
Some political figures in the US are fighting back against this movement; most everywhere else is submitting to the change.
Lets stop getting stuck in minutae of detail and focus on the big picture
This. 100%
“‘It’ never reached ‘pandemic’ status”
Well … it did. But only because the WHO eliminated severity and mortality from the definition of ‘pandemic’, leaving only the criterion of spread.
The interesting fact is that CEBM analysis showed that in the UK, it never reached the level necessary for a definition of an ‘epidemic’ in the community using GP surveillance data.
As far as I know they have been in communication on the matter and Robin Monotti has been providing insights to that.
Strikes me that the differences are due to uncontrolled variables that those collecting the data cannot see due to Cognitive Dissonance or are dropped for political reasons.
They treat people as identical living in identical conditions when they clearly they do not do that.
And yet, there are states in the US, back to normal. The Global elite at the G7 were behaving normally. While people look on and say how wonderful it looks in Cornwall, they see nothing wrong in these people rubbing our noses in restrictions. Its a disgrace, and all of the MP’s are allowing it to happen, turning our free society into a controlled vaccinated one.
Yeah. Not about the virus.
The most danger increased transmission is the scientific clap trap spouted by media “scientists” . They have convinced society that they can stop them dying by stopping them living.
I no longer am willing to accept diktat by fear – Freedom is not a political gift it is a human right.
Brilliant Will. I set out to do this but was defeated by the impenetrable reports. More reports designed to hide rather illuminate information.
Thank you Will for making such an effort.
I repeated PHE’s figure 12 from its most recent report
https://rpubs.com/davehawkins/780798
Just to confirm, from my POV, delta has taken over where alpha left off. Guess what happens next — another variant
Also notable that the high incidences occur in settings where those who test positive are likely young and/or fit and healthy
Perhaps the initial increase in transmissibility of a variant is just the usual Gompertz curve in action, with the new variant spreading relatively rapidly amongst high spreaders and petering out as it infects people who for whatever behavioural or physiological reasons are less and less likely to spread it?
The trouble with statistics (well, one of the many really) is that it treats the whole country as on amorphous group, whereas the reality is that the latest variant is affecting one or two distinct subsections, one particular ethnic group and a second age related group, neither of which has succumbed to the propaganda. The first group do not follow English language news media and the second group have no interest because they have been told they won’t suffer any consequences, so can’t be bothered.
An impressive piece of work, Mr.Jones; thank you.
Some fine work here, joining the dots tha the Regine choose to leave lying around.
Thanks Will
The opening ten minutes of TWiV video 768 (https://www.microbe.tv/twiv/ ) is about how hard it is to determine the transmissibility rate of a virus because the one unknown factor is always human behaviour.
A virus, just like human beings, can be in the right place at the right time (or the reverse) and that determines success or failure. It has taken the research group a year to produce data relating to the European SARS-CoV-2 experience in the late spring / summer/ early fall of 2020.
No expert can truthfully predict what will happen in the next few months since they cannot know how humans will behave. That begs a question about lockdowns and restrictions being the only way politicians can crudely enforce behaviours upon us. That also suggests that zero-Covid19 is still the unrealistic goal of those involved in policy making. As has been suggested by many outliers since the beginning of this pandemic the battle should have involved spreading the virus among those who would not be seriously inconvenienced by infection and act as a hard line for the virus to cross to reach the more susceptible and vulnerable.
Serious cases and fatalities will occur no matter what restrictions are imposed but reducing the opportunity for a virus to find hosts is how we keep all seasonal ‘flu viruses attacks to manageable levels of infection. Surely that is what we should be aiming for with SARS-CoV-2 as well, and lockdowns actually achieve the reverse since there will always be easy pickings for the virus to find unless we have normal spread within the major part of the population. You vaccinate the most vulnerable and allow the spread in others. You do not do stupid things (like locking down) unless you have seriously deprived your health service of realistic capacity and/or you have dismantled a public health structure which would at least have given you the solid basis for a test and trace system.
Set up your own blog will. You’re more in tune with goings on than this site really allows for it seems
Yes sadly there’s a lot of repeating of mainstream opinion ATL but this one stands out
Nice work Will. I was thinking about doing this myself but you beat me to it. Cheers.
The data on infectivity is completely shot – engineered to keep Scary Fairy flying.
There are so many flaws in terms of an explanation related to infection rather than issues of sampling. Essentially – another modellers’ creation.
“… between 85% and 92% of the contacts of all those infected with any of the COVID-19 variants do not get infected. This is an indication of the high level of immunity”
… is the essential take-away sentence, reflecting a similar sort of truth that lies behind the distortion that that emanates from the quotation only of ARR in relation to vaccine efficacy. It’s an entirely partial and biased fragment of the picture.
The image of a virus running rampant was never real, with Swedish data showing that real infectivity within relatively closed indoor groups be only at 17%
Talk Radio are currently carrying a government propaganda advertisement which says one in 3 people are infected with Covid-19 without symptoms and are spreading the disease. This wrong on both counts, and they must know about the data that confirms asymptomatic spread is very minimal in normal circumstances. I know advertising income is difficult to acquire at the moment, but by accepting money to spread government propaganda they are undermining their reputation for honesty.