Can you catch Covid twice? The challenge trials at Oxford University have now turned their attention to this question, deliberately exposing people who have had the disease before to the virus again to see how their immune systems respond.
Other studies have already looked into this question, though without the controversial deliberate exposure aspect. The most recent, published in the Lancet last week, tested around 3,000 U.S. Marine recruits aged 18-20 for Covid antibodies and then followed them over six weeks while they completed basic training together to see how many became infected. The living in close quarters would likely have ensured that all were exposed to the virus.
The study found that around 10% of seropositive (with-antibodies) participants (19 out of 189) tested PCR positive for the virus versus around 50% of seronegative participants (1,079 out of 2,247). This means that having antibodies from a previous infection gives about 80% protection from testing positive for the virus again. This finding closely matches that of a large Danish study published last month, that found those who had tested positive for the virus in the spring were about 80% less likely to test positive again in the autumn. And also a UK study of NHS workers from January that found being PCR positive for the virus at one point made workers around 80% less likely to test positive again at a later date.
The new study was being used last week to promote the idea of vaccinating young people who had previously been infected, on the grounds that protection via infection was not enough. Thus Sky News reported: “Young people who have already tested positive for coronavirus are not fully protected against reinfection.”
The study itself supported this use, stating its results suggest “COVID-19 vaccination might be necessary for control of the pandemic in previously infected young adults”. Professor Stuart Sealfon of Icahn School of Medicine at Mount Sinai, New York, and senior author of the study, said:
As vaccine rollouts continue to gain momentum it is important to remember that, despite a prior COVID-19 infection, young people can catch the virus again and may still transmit it to others. Immunity is not guaranteed by past infection, and vaccinations that provide additional protection are still needed for those who have had COVID-19.
What such claims appear not to allow for is that questions are being asked about how the balance of risks stacks up for young people to be vaccinated even when they have not had Covid, let alone when they have and have 80% protection already. To this balance must be added that severe side-effects are considerably more common in those who have previously had Covid.
The 80% protection figure is also not the full story on immunity following infection. Noteworthy is that symptomatic infection was much less common among those who had antibodies. In fact, only three out of 19 (16%) seropositive PCR positives were symptomatic, versus 347 out of 1,079 (32%) seronegative PCR positives. The large proportion of PCR positive infections that are asymptomatic even among those without antibodies (68%) may be an indication of the high degree of pre-existing immunity among the young.
The infections among those with antibodies were also much less likely to be infectious, with average Ct of 27-28 versus around 24 for the seronegative infections (Ct or cycle threshold corresponds inversely to viral load, which corresponds to infectiousness). This translates to a viral load about ten times lower, which is considerably less infectious.
If we focus just on the symptomatic participants (i.e., people who are actually unwell), then we find three out of 189 (1.6%) symptomatic infections among those with antibodies versus 347 out of 2,247 (15.4%) symptomatic infections among those without. This corresponds to antibodies giving 90% protection against symptomatic Covid (though three is a very small number to base very much on).
The symptoms experienced by these three and the other PCR positive participants are listed in the study, though no indication is given of severity or duration. Indeed, a major weakness of the study is that 21% of those still in the study once on the base ceased to show up for testing, an unknown number of them because they were transferred off the base for unknown medical reasons, which could have been Covid related. This appears to explain why no data is given on Covid hospital admissions or deaths – anyone in that position would just silently have disappeared from the study!
Overall the findings are in line with what we would expect from immunity following viral infection: 80% reduction in testing PCR positive for the virus (some of which will be false or cold positives), 90% reduction in symptomatic disease, much less infectious (ten times lower viral load). Immunity isn’t binary, and can sometimes involve a mild second bout while fighting off the virus with a primed immune system.
Nothing in this study suggests that the immunity acquired by young people through infection needs topping up with vaccination. The lack of data on severity or hospitalisation means it tells us nothing about the risk of serious illness for those previously infected – though the 90% reduction in symptomatic illness intimates it will be considerable. Vaccination, meanwhile, is not risk-free, with any risks (however small) heightened for the previously infected. Young people, like everyone else, should be allowed to weigh up these risks for themselves and decide whether vaccination is right for them – fully informed and free of any coercive pressure.
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Someone look into Professor Stuart S’s funding. Everywhere you look in academic medicine, you find the Gates Foundation.
Please explain this: having covid antibodies “protects” me from testing +ve in a PCR test. What the heck is that supposed to mean? Are we supposed to get the jab to ‘protect us’ from the virus – or from PCR?
It’s still April, so April madness, especially covid madness, reigns supreme …
PCR should be dead in the water, the fact that it’s not is part of the scam! On the WHO
the PCR has a ‘medical alert’, the WHO’s own words are that a medical alert is ‘to warn member states and populations of the existence of a dangerous medical product and encourage increased vigilance and appropriate regulatory action by National Medical Authority/Ministries of health.”
When PCR has been tested in Court, it has invariably failed.
Reiner Fuellmilch, who is heading the global action against PCR, has rightly stated that the PCR “is the cornerstone, and centrepiece of this whole hoax.”
His interview is worth a watch.
Reiner Fuellmich on Viruswaarheid Live Extra.
You can get struck by lightning twice – but it’s very rare.
Never go outside! There’s lightning out there! Get the jibjab to protect other people against lightning!
True story. A friend’s mother was terrified of lightning. when there was a thunderstorm she pulled the curtains and kept away from the windows.
Lightning came down the chimney and zapped her. They found her lying on the floor smoking gently. (She made a full recovery)
Snorting story
Haha – that made me chuckle.
That you can. If you are unfortunate enough to have a weakened immune system due to any cause. I know one individual who has contracted it thrice but as she says, her immune system is shot, for reasons other than covid. If you do contract the lurgy, Vitamin D with K2, B vitamins & magnesium are really important to take to replenish the immune system.
Too late if you’ve already got it.
The vaxx doesn’t help at that stage either.
Stop it, you’re ruining the narrative, I want terror, restrictions, hassle, poverty and tracking for the rest of my life.
PT, Unless the sheep and collaborators do a U turn, I’m afraid we’ve already got it.
Don’t worry: that is now sewn up!
I wonder how a scientist gets the idea that the vaccination with the blueprint of a part of the virus gives “additional protection” to those once infected by the complete virus. A real deep belief in technology and a distrust of nature’s ways? But then the development and effect of vaccines needs brains and immune systems aka nature …
Ok, I have the government’s statement from a year ago (16th April) about how the restrictions might end: “The way out of this is vaccines and… drugs”. They also mentioned 5 tests for the ending of restrictions (and I seem to remember Gordon Brown had 5 tests to be met for joining the eurozone, with the intent apparently of making sure that never happened)..
Well, now over 10 million of the most vulnerable have had the covid jabs if they want them, yet there is still no date for a total, permanent removal of restrictions. Why? And does the government still stand by this statement? If not – were they being deliberately deceptive – or just ignorant? And are they going to try a new strategy? I might suggest boosting natural immunity through orthomolecular medicine, or even just adding vitamin D to some basic foods, as in Finland. But of course there’s no money in that. What is going on?
And note that the ‘and ..drugs’ bit has been studiously ignored.
God forbid that something cheap that could be administered at home could be a prophylactic against severe disease or, even worse, a preventative!
What a waste of money would be the billions spent on the purchase of money sight unseen!
Sorry : the second ‘money’ should have read ‘vaccines’.
Oh dear, why do people keep asking what is going on? Do the research please Agenda 21 and 30.
So our immune systems having evolved over millennia, haven’t been rendered useless within the space of a few months. Good to know.
Great point. However if the WHO is working very hard to replace natural immunity with vaccine ‘derived’ immunity. Now they only refer to vaccine derived immunity.
So is absolute risk reduction from natural immunity 95%>, while from the vaccine it’s <1%? Obviously I must be misunderstanding how this is calculated?
I think you are.
The absolute risk reduction is so low because the chance of catching COVID full stop is not very high over a defined period of time. So whether you have a degree of immunity from previous infection or from a “vaccine”, the absolute reduction is always going to be low.
Basically it’s not that dangerous anyway. So why do we even need a vaccine?
Thanks. I see after looking further, I got that arse about face. Yes, the benefits just aren’t there for the majority and this article reinforces that.
Actually, Posh – you’ve highlighted the deliberate confusion generated by the repetition of relative risk reduction figures. To give an illustration :
If the hospitalization of those not taking a vaccine numbers 10 and the hospitalization of those taking it numbers 4 in comparative groups of 10, (i.e there are 6/10 fewer cases) then the relative risk reduction is 60%. (6/10*100)
However :
Put that in context of the relevant population. If that total population in both treatment and control groups is 100, the absolute risk reduction is (6/100) = 6%. i.e. absolute risk takes account of the numbers involved in the experiment; relative risk merely takes the proportion of the reduction in terms of the difference between those experiencing an adverse event between te two groups.
The significance becomes even clearer if you multiply up the group size to 10,000 or 500,000. And the low single or double digit numbers are not unusual in such experiments : it is easy to see how the real-life odds of risk diminishes drastically from the apparent relative value.
You insist on ignoring the key point which Sophie makes in her comment above, i.e.
The absolute risk reduction is so low because the chance of catching COVID full stop is not very high over a defined period of time.
In your example the 4 hospitalisations is just a sample from a brief time period. Eventually there could be 400 or 4000 hospitalisations depending on the population size.
which defined period of time?
Huh?
The time between the vaccination and the end point when the ‘events’ were analysed.
For Pfizer there were 2 triggers in the following order:
1/ The 170 events were observed which meant the statistical significance of the results provided a high degree of confidence that the ‘vaccine’ was sufficiently effective.
2/ The US election was over which meant the announcement of the results could not favour Trump.
Sadly RickH is too dim to remember that most of us plan to live a lot longer than a defined period of time covering a drug trial (most of us want to live a lifetime) hence over the long period of time the chance of getting covid19 rise towards 100%, Rick is a liar, who won’t admit the truth. Over a long period of time, e.g. a lifetime, the Absolute Risk Reduction rises up to the Relative Risk Reduction. Poor RickH will get it in the end,if he lives long enough.
“Absolute Risk Reduction rises up to the Relative Risk Reduction”
Oh dear! ‘Nuff said. Them cap and bells are on full display here. You’re not arguing with me – you’re denying the mathematics of a basic statistical measure.
Hint : Proportionality in increasing sample size in terms of people and time.
Just go and read up – you can do it on the internet, but I’ll recommend texts if you need them.
Had you in your discourse on the mysteries of time also considered the time limits of vaccine effects?
Agreed, Daily Mail today, Matt Hancock ‘The Government is getting ready to rollout the covid boosters in Autumn.’
That of course doesn’t indicate how many boosters you’ll need for the different variants! Enjoy life as a Government Big Pharma pin-cushion Guinea Pig.
That will be the Cavalry reinforcements riding to the rescue.
No. Too many people already had immunity so the population was nowhere near 100% susceptible (unlike the Trial study). The risk of infection is lower than it was in March 2020.
Theoretically, every non-vaccinated person could be infected over a lifetime – but so could every vaccinated person.
Utterly desperate reasoning there. It’s just so wrong that it shows that any attempt explain why would be as worthwhile as teaching calculus to a chimp.
Mayo – you surely aren’t that dim.
Of course the rarity (or otherwise) of catching Covid is contained within the concept of ‘absolute’ risk reduction. The absolute effect of the ‘vaccine’ remains, no matter what the time period.
That’s the point.
It’s the real world measure that makes it essential data.
You obviously don’t understand sampling, either – the basis of all such experimentation. Get reading.
And be very wary of identifying yourself with the sort of impenetrable dimness and unawareness of basic statistical method displayed by the fonz.
Of course the rarity (or otherwise) of catching Covid is contained within the concept of ‘absolute’ risk reduction. The absolute effect of the ‘vaccine’ remains, no matter what the time period.
Yes and No.
YES – Absolute Risk is not the same as Relative Risk. I know this.
NO – You cannot simply sample over a short time period to calculate AR. You can, though, calculate the Relative risk, e.g. non-vax gets the virus 5 times more than vax.
The AR is dependant on how many people get the virus.
What innumerate has down-voted the statement of a simple statistical fact?
However – it does illustrate how those reality deniers/gullibles who adore the ‘vaccines’ are in La La Land.
Yep agreed. I’m still at more real risk of other diseases like heart disease or cancer, but luckily for everyone I don’t want to shut the country down, put people out of work, Close businesses, make the life of the elderly horrific and unbearable, or throw the lives of young people and children under the bus. I’m one selfish person!
Thanks Rick, that explanation agrees with this one that I looked up.
https://www.meddent.uwa.edu.au/__data/assets/pdf_file/0005/2670593/Risk_reduction_guide0.2.pdf
Just to add, if I understand correctly. If a patient is being offered say, a choice of treatments, then the relative risk reduction could be useful. But if collecting data for a trial and needing to evaluate the impact of that treatment on a large sample, then absolute then becomes a need to know.
Wow. So they use CTs for these studies to set infectiousness levels, but when it comes to locking people down and closing businesses, CTs don’t exist.
OK then. Covid logic 2021
If I read the US study correctly, the study of marine recruits denoted “reinfection” from 1 positive PCR, but only something like 20% of the total test group were IgG positive at the start, so it is not clear how the interaction of the FPR of the PCR will have muddied the waters.
Covid is a SARS type virus. We already had some antibodies to that. That is why many people did not get that sick during these draconian lockdowns. Now people also have antibodies to the more specific ‘covid’ virus
Or to be a bit pedantic, ‘Covid-19’ is the name of a specific disease thought to be caused by a coronavirus classified as SARS-Cov-2. Many of us probably have T-cells which act as long term memories for various other coronaviruses, such as 229E. OCE 43 etc which cause a chunk of so-called ‘common colds’. For most of us, none of them are ‘SARS’ like, and maybe the so-called SARS-Cov-2 isn’t really ‘SARS’ at all (Severe Acute Respiratory Syndrome) for most of us. Maybe it should be renamed in due course, but fairly unlikely; too many assists in the bank for some.
Protection acquired through any vaccine or from recovery from a disease produces agents in the blood which fight the virus once it is is the body. It doesn’t make the virus “bounce off” the body, to use a crude analogy.
So once inside the body they fight the invading virus. The nett result is based on a combination of the anti-bodies and t-cells, the efficiency of the body’s immune system, and the level of the infection (the viral load).
Consequently there will be a spectrum of responses to the infection.
The only possible benefit from having a vaccine and infection-acquired protection is the possibility of a broader range of cover for virus mutation, but this is speculative at best.
For those confused about virus and virions, the link below is a nice well written short description.
Our ‘friend’ SARS2 is the virus and when it infects a cell it willl generate millions/billions of virions which shoot off the infect other cells. Now this happens on such a massive scale that its overwhelmingly likely that virions will not all be the same. So when they infect another cell, the virus produced is not always quite the same, hence the so-called variants.
Our dependable immune system is capable of recognising a virus about 30% or more different and react as if it was the original version. As the current variants are mainly 0.3% ( perhaps up to 0.6% different) the immune system has no problem with them. However it would need somewhere in the region of 100 vaccine jabs to cover the same range , if that was possible at all. Obviously its very likely a lot of people would get very sick from such a stupid process.
SARS2 ( if its really not just a variant of SARS1, which itself etc etc) is endemic, humans just have to live with it, just as intelligent virologists and epidemiologists were saying 12 months ago. The scientists/medics with a ‘god-complex’ need closing down before they wreck the human race.
https://www.virology.ws/2010/07/22/the-virus-and-the-virion/
Big pharma doesn’t care – they have a licence to print money
Neo Liberalism 101
Taken in context of known science, the odds of reinfection with a virus must be vanishingly low – and unusual. I would have thought that this area of research merely illustrates how desperate is the need to find something that is unusual – just like asymptomatic spread – just to justify the hysteria.
Any studies that site the use of the PCR test are essentially bogus and should be ignored.
Jesus wept. Was this study necessary? Who funded this?
Voting for Boris – once is possible, perhaps, but twice? Most unlikely.
Regarding risks of reinfection, here’s my anecdata contribution. As a child I had all the usual real illnesses, measles, German measles, chickenpox, mumps, which all also went round my siblings. Everyone at school had it too. As an adult, I caught rubella on two more occasions (a sibling also got it again), and I also got mumps again. Second rubella (or maybe it was measles, with hindsight I was ill enough to want to lie down for a few days, and the doc only peered at me from a distance, the photos show the rash was rather impressive) was brought into our student block by the teacher trainers, several people caught it. Those that caught it presumably had also had the real thing as a kid, all of similar generation. No great fuss by university, we just got on with it. Second mumps – reckon I caught it off teenagers at a science exhibition I was supporting through work (mid 1990s). Third rubella – through work or social exercise classes, sibling also got it again. Was very fit at the time too, not a couch potato.
So, either immunity wanes or doesn’t work if “run down”, or maybe I caught vaccine variants, to which even the original disease did not offer immunity, or there is the possibility of misdiagnoses. Mumps is rather unmistakeable though.
Still, got a couple of weeks off on full pay each time as infectious, so must have had a cert from the local quack, and used the opportunity to decorate the house.