Evidence (rather than anecdote) about reinfection

[PuzzledObserver]

Was on a Zoom call with a social group and mentioned that at least DH and I are now immune as we try to shake off the Covid symptoms. Of course, I said, we will still abide by whatever rules are in place, but whereas when hospitality was open we didn’t take advantage, now we would.

He said he knows of one nurse through his work (care home provider) who was seriously ill in the first wave and has recently tested positive again, so no, we are not immune and I’ll be going to coffee shops on my own. And of course there are instances of people on MN saying they/someone they know has had a confirmed reinfection.

What I would like is not anecdotes, but statistical evidence. I’m not disputing that a second infection can happen, but I have believed that it is vanishingly rare.

Do you know of any evidence, i.e. statistical studies, about how many people have in fact been infected a second time, as against those who haven’t? The only one I’ve found was the subject of Dr John Campbell’s video a few days ago.

Of 1,038 HCP’s with confirmed infection in the first wave, there were zero cases, either symptomatic or asymptomatic, in the second wave, whereas of more than 10K who escaped the first wave, over 13% tested positive in the second wave.

Anyone found any other studies?

www.journalofinfection.com/action/showPdf?pii=S0163-4453%2820%2930781-7

www.reuters.com/article/us-health-coronavirus-reinfection-idUSKBN28015L

This is from November
I think I read somewhere that reinfections were also less severe

Am aware that is just an article than a proper paper

I wonder if it’s a news report on the same paper? It cobpvers the same time period, was also an unreviewed pre-print about UK healthcare staff.

This is a study with much larger numbers (over 100,000) from Qatar - shows reinfection rate of 0.05%. Very reassuring.

pubmed.ncbi.nlm.nih.gov/33315061/

Also interested to know this. There seem to be a lot of people who say they "definitely" had it in Feb or whatever and have since had it again. Of course it then turns out they weren't tested in Feb (of course) so in all likelihood had something else.

I do know of one case of reinvention which is still anecdotal - my mum's consultant tested positive in April and tested positive again last week. Says she definitely felt more unwell in April but still feels very under the weather this time round.

I'm not sure about reinfection but my mum had Covid in April. She was tested for antibodies in August and had them. She was then retested for antibodies this week and no longer has them. (She is NHS frontline). So it could be that antibodies only last around 6 months and then people can get Covid again.

Even if you don't have antibodies after infection it doesn't mean you're not immune because you will have t-cell and B-cell immunity which will jump into action and produce antibodies if you come into contact with the virus again.

@Partedinsurprise I agree that “I definitely had it” isn’t strong enough evidence. After all, most people who have a test are negative. And they went for a test because they had symptoms which suggest Covid... but it wasn’t.

I changed my mind at least six times as to whether I thought I had it or not.

My colleague swore she'd had it earlier in the year, around Jan/Feb time. We had antibody tests in the summer - she was negative. Then she (and I!) had confirmed Covid in November.
I suspect there was a horrid viral bug last winter that people are really hoping was Covid..... but probably wasn't.

It’s too early to tell yet because big problem with separating anecdote from data is in the first wave, you could only get a test if you required admission to hospital. So the vast majority of people who did have covid and may now have it a second time, cannot say for absolute sure. Anecdotally, I live in London and am hearing of more and more people who believe they are infected a second time...logically this would fit because guesses seem to be that post infection immunity lasts 6-9 months (this varies between individuals and T cells may be at work even if antibodies are not) and there is a rampant new strain just as that period is ending. It’s why there’s a flu jab every year, I wouldn’t be surprised if covid behaves the same way.

It’s too early to tell yet because big problem with separating anecdote from data is in the first wave, you could only get a test if you required admission to hospital.

The Qatari study didn’t have that problem.

I am following with interest as my niece's FIL who was hospitalised with confirmed Covid in May , has just been readmitted to hospital with a high temperature and has tested positive again.
He was discharged from hospital after a few days in May and had a negative test after 3 weeks so this is unlikely to be the same infection since it is 8 months later
I know this is anecdotal but it has made me more interested in the data available on reinfection

Sorry to hear about your relative, @bumblingbovine49. There are always going to be a few cases, which are concerning for those directly involved. But if reinfection was a frequent occurrence we would have (even) more to worry about.

There will also be some people who catch it despite being vaccinated - but hopefully not many.

@PuzzledObserver

It’s too early to tell yet because big problem with separating anecdote from data is in the first wave, you could only get a test if you required admission to hospital.

The Qatari study didn’t have that problem.

The Quattro study only used 64 days as the basis for reinfection? Its strongest statement is that immunity lasts ‘at least a few months’. I don’t think there’s been any suggestion that reinfection is occurring that quickly, even anecdotally.

Quatar not Quattro obvs

Whitty, this morning:

Is it possible to be reinfected with Covid?

That was the question from a couple who are still showing symptoms after being diagnosed on 20 December. Prof Whitty says it's possible, but the risk of getting Covid-19 a second time is "much reduced".

The same will be true after vaccination, he says: "Reinfections will occur but at a much lower rate."

He says Covid does not last as an infection for very long periods of time, except in unusual circumstances, but symptoms can continue for a "very long period of time".

Prof Whitty adds there is then the issue of long Covid - "this is people who have long-term problems, which do for most people improve over time".

This published today:

www.gov.uk/government/news/past-covid-19-infection-provides-some-immunity-but-people-may-still-carry-and-transmit-virus

I was initially rather disappointed with the 83% protection, however I note that of the 44 cases, only 2 were categorised as probable and 42 were possible.

I was kind of hoping that the Covid Symptom Tracker app might produce some data on this.

The evidence of redirection is the opposite to how they have established that having Corona imbues 86% immunity. The data comes from the Siren study, which is tracking NHS staff.
See here - www.gov.uk/government/news/past-covid-19-infection-provides-some-immunity-but-people-may-still-carry-and-transmit-virus

Reinfection not redirection!

I definitely had it in March and again in December. It happens and is happening to quite a few of the first wave , although few can prove it unless they had access to testing the first time round. It's not terribly surprising, we know antibodies wane (I had some in July but they were gone by September, ). Nor is it terribly worrying as most (but not all) second infections are reported to be milder.