We have more immunity to SARS-CoV-2 than thought

yorkie

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Firstly, a lot of people appear to think that anyone who does not have SARS-CoV-2 antibodies has no immunity against the virus; this is false.

Anyone who has been exposed to other coronaviruses (some of which are deemed to be "common cold" viruses, though not all "common cold" viruses are coronaviruses; many are actually rhinoviruses ) will likely have at least some immunity; depending on the strength of the persons immune system, and the dose of infection and other factors, it is very possible that many people can fight off SARS-CoV-2 without experiencing severe symptoms, or any symptoms at all, without having to produce any antibodies.

Here are some interesting articles; firstly to understand a bit more about T-cells:


T cells—another subset of the adaptive response—are often left out of conversations about immunity.

“You can’t have a great antibody response without T cells,” says Akiko Iwasaki, a virologist and immunologist at Yale University. Among a slew of helpful functions, T cells help young B cells mature into antibody-making machines. “These things really go hand in hand.”

T cells are also formidable fighters in their own right. In a bid to stop the spread of a pathogen throughout the body, some T cells will trigger infected cells to self-destruct. Others linger after an illness has resolved, patrolling tissues so germs can’t reestablish a foothold. (One of the reasons that HIV is such a devastating diagnosis is that the virus destroys some of the body’s T cells.)

Studies of other coronaviruses, including the ones that cause SARS and MERS, show that T cells play integral roles in stamping out sickness...
The article also goes on to say:
...That doesn’t mean people are doomed to experience the same diseases over and over. “The word ‘immune’ makes it sound like the virus gets close to your body, hits a wall, and has to turn away and go find someone else,” says Allison Roder, a virologist at New York University. But even partial protection from the immune system will curtail the amount of pathogen in a person’s body, and, by extension, the likelihood of transmission..."
And here is another article, which talks about how there appear to be different levels of immunity in different populations:

One thing seems clear: there are many reasons why one population is more protected than another. Theoretical epidemiologist Sunetra Gupta of the University of Oxford thinks that a key one is immunity that was built up prior to this pandemic. “It’s been my hunch for a very long time that there is a lot of cross-protection from severe disease and death conferred by other circulating, related bugs,” she says. Though that cross-protection may not protect a person from infection in the first place, it could ensure they only experience relatively mild symptoms.'
The article goes on to say:
In a paper published in Cell on 14 May, researchers at the La Jolla Institute for Immunology in California reported that T cells in blood drawn from people between 2015 and 2018 recognised and reacted to fragments of the Sars-CoV-2 virus. “These people could not have possibly seen Sars-CoV-2,” says one of the paper’s senior authors, Alessandro Sette. “The most reasonable hypothesis is that this reactivity is really cross-reactivity with the cousins of Sars-CoV-2 – the common cold coronaviruses which circulate very broadly and generally give rather mild disease.”

The finding supported an earlier one from a group at the Charité hospital in Berlin, detecting T cell reactivity to proteins in the Sars-CoV-2 virus in 83% of Covid-19 patients but also in 34% of healthy volunteers who had tested negative for the virus itself....
While a lot of the facts remain unknown, it's increasingly obvious - and undeniable - that the unexposed population has at least some immunity to SARS-CoV-2 and therefore the claims that some people make, along the lines of "only 7% (or whatever) of the population are immune" is totally untrue; that said we do not know exactly what the actual percentages are, and based on the evidence available so far, it is extremely likely to vary by country/region and other population factors.

Here is a fascinating video; if anyone is particularly interested I'd recommend watching the full thing, but if you are short for time, just watch the first 10 mins or so, the bit around the 1 hour mark, and the summary at the end:
I really do recommend people watch this, or at least part of it!

For anyone unable to access the video, a brief summary is that evidence is emerging that strongly suggests there are many 'categories' of immunity, but the exact proportions who are immune is not yet fully known.

The disgraced Professor Ferguson's model - which was proven to be deeply flawed - assumed that no-one had any immunity; see numerous existing threads where this has cropped up (e.g. https://www.railforums.co.uk/threads/coronavirus-how-scared-should-we-be.204710/page-4#post-4595085 and https://www.railforums.co.uk/threads/should-our-lockdown-have-been-harsher-stricter.205224/page-2 among other threads). We can be confident this assumption was completely false, though we cannot be confident as to exactly how many people are already immune.

Edit: Now I've learnt a lot more about how the body's immune system works, I now have a much better idea of the answers to a question I asked back in April: https://www.railforums.co.uk/threads/am-i-lucky-with-viruses.203890/
 
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Bantamzen

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I would also recommend watching the video, its an interesting discussion on not only how the immune system takes a multi-faceted approach to viruses, but also how immunity could potentially be far more widespread thanks to exposure to other viruses of the same family, and why anti-body testing isn't necessarily as precise a measure of immunity as some might have it be.
 

takno

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I'd rather watch a video featuring someone with qualifications and experience in the field - not a NASA Computer Scientist. Here's Creon Levit's CV
I'm sure if you find us all a video to watch that clearly explains things in this kind of detail and does feature someone with qualifications and experience in the field, then we will all watch it
 

Puffing Devil

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I'm sure if you find us all a video to watch that clearly explains things in this kind of detail and does feature someone with qualifications and experience in the field, then we will all watch it
I'm sure I could, though that wasn't the point of my post. Do not attach too much credence to well-produced videos posted on an open platform with no peer review or a presenter with no substantive qualification in a subject. That's how we end up with drinking bleach and sticking UV lights where they shouldn't be shining.
 

Bantamzen

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I'm sure I could, though that wasn't the point of my post. Do not attach too much credence to well-produced videos posted on an open platform with no peer review or a presenter with no substantive qualification in a subject. That's how we end up with drinking bleach and sticking UV lights where they shouldn't be shining.
If you had bothered to watch it you'll have known that they referenced their discussion on a peer reviewed paper.
 

takno

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I'm sure I could, though that wasn't the point of my post. Do not attach too much credence to well-produced videos posted on an open platform with no peer review or a presenter with no substantive qualification in a subject. That's how we end up with drinking bleach and sticking UV lights where they shouldn't be shining.
If it helps, I didn't think it was particularly well-produced, don't ascribe any particular credence to the channel, and was extremely suspicious of it being a NASA scientist rather than one with relevant qualifications. It was a a detailed discussion based around a decent quality paper on the subject though, and chimed well other stuff I've read and seen on the topic in peer-reviewed paper and respectable popular science publications. Furthermore, it didn't actually make any very substantial claims beyond suggesting that there is some interesting stuff going on and the effects are worth modelling.
 

MikeWM

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I watched the whole thing and found it very interesting and very informative; I’d recommend anyone who wants to know more about this disease in particular, and the human immune system in general, to give it a go.
 

Puffing Devil

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Rhetorical appeals to Ethos are a poor substitute to logical critique.
You're beginning to sound like a stuck record. This is an internet forum, where people express a point of view, not the school debating society.

Everyone has a choice about their sources of information and education. In this case, I prefer to look beyond two engineers with books and social platforms to push. Yes, they do reference published papers. Are the papers pertinent? Have they cherry-picked the arguments? Have they used the information well, or selectively used it to promote their own position? I really don't know and have no interest in investing my time in a video podcast series with no bona fides.
 

yorkie

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If people don't want to believe that we already have some immunity, that's up to them, but I await any other explanation for what we're seeing happening!
 

edwin_m

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If people don't want to believe that we already have some immunity, that's up to them, but I await any other explanation for what we're seeing happening!
What are we seeing happening?

Although UK deaths are still falling this is a lagging indicator and also affected by improvements in treatment (dexamethasone should cut it by about a third over the next few weeks if study results are to be believed). More leading indicators, particularly hospital admissions in several regions, have stopped falling. The number of positive tests per day also abruptly stopped falling a week or so back, although this is difficult to interpret because it depends on the rate of testing, which varies wildly day by day. But there is some evidence that the recent relaxation in restrictions, while not leading to a second wave, has at least increased the effective reproduction rate close to 1. The next set of relaxations are likely to involve social venues where people are talking, eating and drinking in proximity - probably higher risks of transmission than shops or public transport.

There are some interesting ideas in the video but all unproven at present, so it wouldn't be right to justify lifting measures on the basis that we might have herd immunity already. More research is needed. I'm also inclined to think that if the effective herd immunity level was increasing more than the antibody tests suggested, then the rate of new cases would have started to slow before lockdown as the level of immunity started to limit the effective reproduction rate. I'm not sure the pre-lockdown figures showed any evidence of that happening, though it may be swamped by other effects.
 

yorkie

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What are we seeing happening?

Although UK deaths are still falling this is a lagging indicator and also affected by improvements in treatment (dexamethasone should cut it by about a third over the next few weeks if study results are to be believed). More leading indicators, particularly hospital admissions in several regions, have stopped falling. The number of positive tests per day also abruptly stopped falling a week or so back, although this is difficult to interpret because it depends on the rate of testing, which varies wildly day by day. But there is some evidence that the recent relaxation in restrictions, while not leading to a second wave, has at least increased the effective reproduction rate close to 1. The next set of relaxations are likely to involve social venues where people are talking, eating and drinking in proximity - probably higher risks of transmission than shops or public transport.

There are some interesting ideas in the video but all unproven at present, so it wouldn't be right to justify lifting measures on the basis that we might have herd immunity already. More research is needed. I'm also inclined to think that if the effective herd immunity level was increasing more than the antibody tests suggested, then the rate of new cases would have started to slow before lockdown as the level of immunity started to limit the effective reproduction rate. I'm not sure the pre-lockdown figures showed any evidence of that happening, though it may be swamped by other effects.
OK how else would you explain what's happening in Stockholm? They didn't lock down; Prof Ferguson predicted huge numbers of deaths and that never happened.

If there is no existing immunity, why didn't London - which was the worst affected city in the UK - continue to have large numbers of cases? If the only people with any immunity are those with antibodies, why did the rate of infections slow down in London before anywhere else?
 

Camden

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yorkie said:
it's increasingly obvious - and undeniable - that the unexposed population has at least some immunity to SARS-CoV-2 and therefore the claims that some people make, along the lines of "only 7% (or whatever) of the population are immune" is totally untrue; that said we do not know exactly what the actual percentages are, and based on the evidence available so far, it is extremely likely to vary by country/region and other population factors.
The first part of this claim is bold and fits neither the science nor circumstance.

The novel introduction, lack of exposure and unusual structure of this virus means that it spreads very easily, including infecting not just humans but some other animals, as we have seen and continue to see. That is an undeniable fact measured in infections and deaths.

Further, the universally consistent spread of the virus around the globe shows that there is little to no immunity crossover for this particular virus (else certain populations would escape it, whereas any variations have simply been down to containment policies).

I really don't think Prof Ferguson is especially "disgraced" any more so than the many, many mainly men in this country who have put their own personal wants above looking after others. The number of groups of men, teens to 50s, that I have seen on bikes, in groups in parks, and other guideline or rules flouting ways, is vast. Many men have seemed to exude a casual indifference and unwillingness to comprehend both personal danger and particularly the danger they may pose to others.

Perhaps Stockholm's non-lockdowned menfolk have been rather better behaved during this time than so many men in the UK have.

Prof Ferguson resigned because his actions went against the actions his science supported. It is notable that he stated he only did this because he had antibodies, and further notable that he stood by his science by resigning.

By all means, learn about the immune system. But I don't believe anyone should be encouraging anyone to believe that immunity may be higher than we currently know it to be. That is just a words version of gathering in parks.
 

MikeWM

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I'm also inclined to think that if the effective herd immunity level was increasing more than the antibody tests suggested, then the rate of new cases would have started to slow before lockdown as the level of immunity started to limit the effective reproduction rate. I'm not sure the pre-lockdown figures showed any evidence of that happening, though it may be swamped by other effects.
I’ve seen graphs people have done trying to calculate our favourite number R, and they show that R fell rapidly in the couple of weeks before lockdown, and went below 1 around March 21st.

Now as we know it is hard to calculate R accurately, and Ferguson says something different (but I think we can safely ignore him on the basis of past performance). But to me this makes intuitive sense - as deaths peaked on April 8th, it seems unlikely R could have still been high at the time of lockdown (doesn’t seem to give enough time for people to develop symptoms, get ill and die, in that window before April 8th)

These graphs also appear to show that the graphs of R in the UK (‘late’ lockdown), Germany (‘early’ lockdown) and Sweden (‘no’ lockdown) are fairly indistinguishable.
 

yorkie

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I have nothing further to add.
Quite!

But I am really interested in why his model was so incredibly was wrong, and the more I read, the more obvious it becomes: there has to be some immunity in the population already in existence. There doesn't appear to be any other explanation that makes sense.

Here is another good article:

Immune warriors known as T cells help us fight some viruses, but their importance for battling SARS-CoV-2, the virus that causes COVID-19, has been unclear. Now, two studies reveal infected people harbour T cells that target the virus—and may help them recover. Both studies also found some people never infected with SARS-CoV-2 have these cellular defences, most likely because they were previously infected with other coronaviruses.
The teams also asked whether people who haven’t been infected with SARS-CoV-2 also produce cells that combat it. Thiel and colleagues analyzed blood from 68 uninfected people and found that 34% hosted helper T cells that recognized SARS-CoV-2. The La Jolla team detected this crossreactivity in about half of stored blood samples collected between 2015 and 2018, well before the current pandemic began. The researchers think these cells were likely triggered by past infection with one of the four human coronaviruses that cause colds; proteins in these viruses resemble those of SARS-CoV-2.
The first part of this claim is bold and fits neither the science nor circumstance.
The evidence suggests it does.
The novel introduction, lack of exposure and unusual structure of this virus means that it spreads very easily...
Yes, up to a point, and then it slows down, long before herd immunity would be reached if you only include people with antibodies. Why do you think that could be?
Further, the universally consistent spread of the virus around the globe shows that there is little to no immunity crossover for this particular virus (else certain populations would escape it, whereas any variations have simply been down to containment policies).
If there is little to no immunity, why did we see places that were hardest hit slow down earlier than other places, and yet the decelleration in the rate of infections occurred when relatively few people had gained antibodies?
Perhaps Stockholm's non-lockdowned menfolk have been rather better behaved during this time than so many men in the UK have.
This is an absurd suggestion; you can continue getting your hair cut, go to restaurants/pubs over there, for example.
 

Richard Scott

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There was a quote from a doctor in Milan a while back alluding to the viral loading of recent people testing positive was vastly reduced and he concluded the virus was as good as finished in Italy. May be a bold statement but certainly seems to fit in with what we are seeing?
 

MikeWM

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There was a quote from a doctor in Milan a while back alluding to the viral loading of recent people testing positive was vastly reduced and he concluded the virus was as good as finished in Italy. May be a bold statement but certainly seems to fit in with what we are seeing?
There was a doctor in Birmingham earlier saying something similar - that some people were still ending up in hospital, but effectively no-one in his area was getting bad enough to end up in ITU anymore.

Sorry, but not sure where I saw that now so can’t provide a link.
 

bspahh

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Here is another good article:
The studies that article quotes are on 10-100 patients. It is possible to get useful information from that size of sample, but it needs expert knowledge. It is easy for errors from random variation, and from conscious and unconscious bias to be bigger than the effect that you're looking to measure.

Derek Lowe is a well-respected medicinal chemist, who has written a blog "In the Pipeline" https://blogs.sciencemag.org/pipeline/ for a while now. Its now hosted by Science magazine. His day job is as a Director of Chemical Biology at Novartis in the US. Every so often, he has written about things that I know about, and he has been pretty level headed.

These are his posts on Covid-19 https://blogs.sciencemag.org/pipeline/archives/category/covid-19

I'm not a chemist, but https://blogs.sciencemag.org/pipeline/archives/2008/02/26/sand_wont_save_you_this_time is well worth a read, as are his other posts with the tag
"Things I Won't Work With" https://blogs.sciencemag.org/pipeline/archives/category/things-i-wont-work-with
 

Abpj17

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OK how else would you explain what's happening in Stockholm? They didn't lock down; Prof Ferguson predicted huge numbers of deaths and that never happened.

If there is no existing immunity, why didn't London - which was the worst affected city in the UK - continue to have large numbers of cases? If the only people with any immunity are those with antibodies, why did the rate of infections slow down in London before anywhere else?
As is implied for Paris, given London's international connections, the virus was likely circulating in London well before March. A material number already had and, particularly in the centre, the lockdown in London was severe and effective. This partially reflects that large numbers of London's population are well paid services that can be done from home (lawyers, accountants, bankers) and mass reduction on train commuting. The big corporates were already moving to mass working from home or week on / week off patterns before the formal lockdown. (Tube/bus within greater London and poor paid service workers that can't work from home paints a different picture tho)
 

Skimpot flyer

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OK how else would you explain what's happening in Stockholm? They didn't lock down; Prof Ferguson predicted huge numbers of deaths and that never happened.

If there is no existing immunity, why didn't London - which was the worst affected city in the UK - continue to have large numbers of cases? If the only people with any immunity are those with antibodies, why did the rate of infections slow down in London before anywhere else?
One could also add, given the first London mass gatherings / protests for Black Lives Matter were now more than two weeks ago, why has there not been a big spike in new infections? Many of those attending the protests were in close proximity for more than 15 minutes, many not wearing face coverings, either. If the incubation period can be up to 14 days, surely there would be some increased level of cases by now?
None of the mainstream media seem to have picked-up on this lack of a spike in new infections in London. Perhaps because it doesn't fit the doom-and-gloom narrative they are constantly peddling?
 

Abpj17

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One could also add, given the first London mass gatherings / protests for Black Lives Matter were now more than two weeks ago, why has there not been a big spike in new infections? Many of those attending the protests were in close proximity for more than 15 minutes, many not wearing face coverings, either. If the incubation period can be up to 14 days, surely there would be some increased level of cases by now?
None of the mainstream media seem to have picked-up on this lack of a spike in new infections in London. Perhaps because it doesn't fit the doom-and-gloom narrative they are constantly peddling?
It's been refer to in MSM somewhere. The active cases in London were already very low by then (unclear how many travelled in from a long distance tho) and many were masked. If they had travelled in - which is clearer that some of the troublemakers did - then those cases wouldn't be reported in London but back in their home towns.
 

Bayum

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Although Ferguson modelled on the basis that no one had immunity, surely it was better to make that assumption when it is a new virus, caused thousands of deaths around the world before had even got itself transmitting through the English population.
 

Bantamzen

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As is implied for Paris, given London's international connections, the virus was likely circulating in London well before March. A material number already had and, particularly in the centre, the lockdown in London was severe and effective. This partially reflects that large numbers of London's population are well paid services that can be done from home (lawyers, accountants, bankers) and mass reduction on train commuting. The big corporates were already moving to mass working from home or week on / week off patterns before the formal lockdown. (Tube/bus within greater London and poor paid service workers that can't work from home paints a different picture tho)
Potentially it wasn't just London, there is evidence that it was spreading in the UK as far back as January, maybe even December right where I live. There were a string of cases with covid-like symptoms that emerged following a businessman's return from Wuhan province back in mid-December. And the suggestion that being exposed to other coronaviruses might afford some level of immune system recognition is interesting in this context, because this winter just gone my wife an I had a string of colds that we just couldn't shake. Now if covid was on the move here in Baildon, and its very likely because one of the people badly affected was the landlady of one of the local pubs, then there is a strong possibility we would have been exposed yet neither of us have had anything like the symptoms. So did those colds trigger enough immunity to prevent us suffering from it? I can only speculate, but its certainly an interesting notion that seems to have at least some traction.

One could also add, given the first London mass gatherings / protests for Black Lives Matter were now more than two weeks ago, why has there not been a big spike in new infections? Many of those attending the protests were in close proximity for more than 15 minutes, many not wearing face coverings, either. If the incubation period can be up to 14 days, surely there would be some increased level of cases by now?
None of the mainstream media seem to have picked-up on this lack of a spike in new infections in London. Perhaps because it doesn't fit the doom-and-gloom narrative they are constantly peddling?
I've mentioned this on another thread, but the two May bank holidays that some were expecting to trigger spikes simply did not. Even after three weeks from each one, the 7 day rolling average fell consistently, strongly suggesting that despite all the fears they did not cause any upturn in infection rates.

It is very interesting that details like these seem to slide conveniently under the radar. And when one set of numbers don't go the way the media editors might like (for sales / clicks), they simply move onto another set of numbers.
 

nedchester

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There was a doctor in Birmingham earlier saying something similar - that some people were still ending up in hospital, but effectively no-one in his area was getting bad enough to end up in ITU anymore.

Sorry, but not sure where I saw that now so can’t provide a link.
There are no Covid-19 patients in intensive care at England’s largest hospital trust for the first time since the pandemic began, its chief executive has said.

Dr David Rosser, who heads the University Hospitals Birmingham NHS Foundation Trust (UHB), also said there were signs coronavirus-infected patients “don’t seem as sick, on average, as they were”.

Speaking on a webinar with regional journalists on Friday, he said the trust had lost 30% of its normal treatment capacity for ordinary services having to cope with Covid-19.

Dr Rosser also said Apple and Google were “disgraceful” for not doing more to ensure the now-scrapped NHS contact tracing app could work across both firm’s operating platforms.

The West Midlands has been among the hardest hit regions in the country by the virus, with 4,735 dying after testing positive for Covid-19.
 
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DerekC

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Firstly, a lot of people appear to think that anyone who does not have SARS-CoV-2 antibodies has no immunity against the virus; this is false.

Anyone who has been exposed to other coronaviruses (some of which are deemed to be "common cold" viruses, though not all "common cold" viruses are coronaviruses; many are actually rhinoviruses ) will likely have at least some immunity; depending on the strength of the persons immune system, and the dose of infection and other factors, it is very possible that many people can fight off SARS-CoV-2 without experiencing severe symptoms, or any symptoms at all, without having to produce any antibodies.
I watched the video attached to your post, which was fascinating - thanks for that. And I agree that it seems to be based on genuine peer reviewed research. It begins to explain some of the complexities of the Coronavirus epidemic.

One question I was left asking is how this relates to the "R" number, which is as I understand it a measured value based on the average number of people inflected by each infected person. The video made clear that body has multi-layered defences against viruses and if the first levels work (for example the mucus membranes prevent entry), then presumably the person will never test positive, so the "R" will already take this into account. Putting it another way, at which level does a person start to test positive?
 

Bayum

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I watched the video attached to your post, which was fascinating - thanks for that. And I agree that it seems to be based on genuine peer reviewed research. It begins to explain some of the complexities of the Coronavirus epidemic.

One question I was left asking is how this relates to the "R" number, which is as I understand it a measured value based on the average number of people inflected by each infected person. The video made clear that body has multi-layered defences against viruses and if the first levels work (for example the mucus membranes prevent entry), then presumably the person will never test positive, so the "R" will already take this into account. Putting it another way, at which level does a person start to test positive?
When the virus is detected in testing.
 

philosopher

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Quite!

But I am really interested in why his model was so incredibly was wrong, and the more I read, the more obvious it becomes: there has to be some immunity in the population already in existence. There doesn't appear to be any other explanation that makes sense.

The evidence suggests it does.

Yes, up to a point, and then it slows down, long before herd immunity would be reached if you only include people with antibodies. Why do you think that could be?

If there is little to no immunity, why did we see places that were hardest hit slow down earlier than other places, and yet the decelleration in the rate of infections occurred when relatively few people had gained antibodies?

This is an absurd suggestion; you can continue getting your hair cut, go to restaurants/pubs over there, for example.
The Southeast Asian countries of Thailand, Vietnam, Cambodia and Laos have barely been impacted by this pandemic. Laos has had only 19 cases and 0 deaths. Laos’s population is over 7 million. I know some will say these countries did amazing contact tracing, closed borders early, etc but the figures for these countries are so low that I think something must be going on in these countries to result in such low figures. There was a Times article yesterday saying there was likely pre existing immunity in these countries which explain the low incidence in these countries.

These countries are all close to China and probably would have had quite a few tourists from China in January before the extent of the pandemic become clear.
 

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