COVID-19 Reinfection

[AsherO]

Great news!

https://medicine.wustl.edu/news/good-news-mild-covid-19-induces-lasting-antibody-protection/

How could they claim a lifetime of protection if COVID’s only been around for <1.5 years?

I’m not saying they’re wrong, just trying to understand.

[gozalim]

How could they claim a lifetime of protection if COVID’s only been around for <1.5 years?

I’m not saying they’re wrong, just trying to understand.

read the article. something to do with bone marrow

[ae123]

Breaking news. The science is slowly catching up to common sense.

Not really.
This was a relatively small study & they seem to be moving on to monitor immunity in vaccinated people.
I've actually been trying for some time through medical contacts to get studies done on natural immunity and oddly there doesn't seem to much interest. It's all "just take the vaccine".

[biobook]

How could they claim a lifetime of protection if COVID’s only been around for <1.5 years?

I’m not saying they’re wrong, just trying to understand.

After infection, B cells produce antibodies, but these cells have a short lifespan.  Some B cells become memory B cells, and have a longer lifespan.  Upon reinfection, they can quickly multiply and produce a large number of B cells that churn out antibodies.  So long-term immunity depends on these memory B cells. 

Based on general principles of immunity, it was assumed that memory B cells would be produced, though how long they last was uncertain.  Most of these memory B cells are sequestered in the bone marrow, so not exactly easy to study.  Here they found these memory B cells were still around 11 months after infection, so they're the kind of cells that are found in lifelong immunity, but I agree with you that they can't be certain that they'll last that long.  Some long-term immunity is on the order of a few years.

[ExGingi]

After feeling constantly tired for several days, followed by some muscle pain and feeling cold (despite it not being cold around), I thought that maybe I got reinfected with COVID. I had no fever, and no other symptoms (some other family members were not feeling well with fever, and suspected strep). Luckily I had a home BinaxNow antigen test, which I used, and it came back negative (I also happened to take an antigen test at a test location a week earlier, in order to be allowed into a hospital, and that came back negative).

This morning I got news that my daughter, who we were sure had strep due to several days of a sore throat, tested positive for COVID (after strep test came back negative).

I wonder if having the symptoms I had is somehow related to being exposed and my immune system fighting it off (I did previously test for very high antibody levels, though I haven't tested those in a while). @biobook any input?

[Dan]

After feeling constantly tired for several days, followed by some muscle pain and feeling cold (despite it not being cold around), I thought that maybe I got reinfected with COVID. I had no fever, and no other symptoms (some other family members were not feeling well with fever, and suspected strep). Luckily I had a home BinaxNow antigen test, which I used, and it came back negative (I also happened to take an antigen test at a test location a week earlier, in order to be allowed into a hospital, and that came back negative).

This morning I got news that my daughter, who we were sure had strep due to several days of a sore throat, tested positive for COVID (after strep test came back negative).

I wonder if having the symptoms I had is somehow related to being exposed and my immune system fighting it off (I did previously test for very high antibody levels, though I haven't tested those in a while). @biobook any input?

Decent odds it was a false negative.

[ExGingi]

Decent odds it was a false negative.

twice?

[biobook]

After feeling constantly tired for several days, followed by some muscle pain and feeling cold (despite it not being cold around), I thought that maybe I got reinfected with COVID. I had no fever, and no other symptoms (some other family members were not feeling well with fever, and suspected strep). Luckily I had a home BinaxNow antigen test, which I used, and it came back negative (I also happened to take an antigen test at a test location a week earlier, in order to be allowed into a hospital, and that came back negative).

This morning I got news that my daughter, who we were sure had strep due to several days of a sore throat, tested positive for COVID (after strep test came back negative).

I wonder if having the symptoms I had is somehow related to being exposed and my immune system fighting it off (I did previously test for very high antibody levels, though I haven't tested those in a while). @biobook any input?

I am not a doctor, and don't even play one on DDF.  I would advise seeing your family doctor.

In theory, all the things you've considered sound possible.
Maybe you had a very low covid infection, so some symptoms, but your immune system fought it off, so no antigen measurable in the binax test this week.
Maybe you encountered covid last week, right after your negative test, hence the symptoms, and also passed it on to your daughter, but easily fought off the virus, so no longer have enough for a positive binax test.
Maybe you do have covid, but the binax test is giving a false negative.  IIUC, the tests are temperature-sensitive and the reagents degenerate over time.
Maybe your symptoms relate to long covid, related to your first infection.
Maybe your symptoms relate to one of the myriad conditions that caused tiredness and muscle pain even in the pre-covid era.
Perhaps you want to take a PCR test, to reassure yourself that you're not infectious now to others or, if you are infectious, so that you can isolate.
But mostly I think you should pose your question to your personal physician, who presumably is familiar with both covid and your medical history.

[Dan]

twice?

Antigen tests are not very good for Omicron.

[ExGingi]

I am not a doctor, and don't even play one on DDF.  I would advise seeing your family doctor.

In theory, all the things you've considered sound possible.
Maybe you had a very low covid infection, so some symptoms, but your immune system fought it off, so no antigen measurable in the binax test this week.
Maybe you encountered covid last week, right after your negative test, hence the symptoms, and also passed it on to your daughter, but easily fought off the virus, so no longer have enough for a positive binax test.
Maybe you do have covid, but the binax test is giving a false negative.  IIUC, the tests are temperature-sensitive and the reagents degenerate over time.
Maybe your symptoms relate to long covid, related to your first infection.
Maybe your symptoms relate to one of the myriad conditions that caused tiredness and muscle pain even in the pre-covid era.
Perhaps you want to take a PCR test, to reassure yourself that you're not infectious now to others or, if you are infectious, so that you can isolate.
But mostly I think you should pose your question to your personal physician, who presumably is familiar with both covid and your medical history.

Except that I'm mostly feeling better now, so I'm not sure what a PCR test would do.

[biobook]

twice?

Two false negatives might be rare if this were two unrelated random tests.
But you know you were exposed to at least one positive case, so your tests aren't random.  Having that exposure plus having symptoms makes you more likely to be infected yourself, so a PCR might be warranted.

[ExGingi]

Two false negatives might be rare if this were two unrelated random tests.
But you know you were exposed to at least one positive case, so your tests aren't random.  Having that exposure plus having symptoms makes you more likely to be infected yourself, so a PCR might be warranted.

Even after symptoms are mostly gone?

[biobook]

Except that I'm mostly feeling better now, so I'm not sure what a PCR test would do.

Wouldn't it let you know if you're still contagious, should isolate?

[moko]

Antigen tests are not very good for Omicron.

and yet they're accepted for travel even though the vast majority of COVID cases are currently omicron....go figure. Not to mention the emed tests which are so easy to fake but that's way OT

[moko]

Wouldn't it let you know if you're still contagious, should isolate?

how would it do that? Is t the current recommendation only 5 days isolation? If you take the test after feeling mostly better wouldn't it still show positive even if isolation is no longer necessary?

[Dan]

and yet they're accepted for travel even though the vast majority of COVID cases are currently omicron....go figure. Not to mention the emed tests which are so easy to fake but that's way OT

The testing is a joke at this point. The US gov't moves as a snail's pace, so we need a judge to bring down rules.
Do you mean photoshop? That's always been the problem with requiring PCRs unless the location receives them from the source, like Hawaii was doing.

[biobook]

I'm not uptodate on this, so here's a very recent summary of what to do, when, if you've tested positive and/or have been in contact with someone who has. 
https://www.nbcchicago.com/news/coronavirus/how-long-are-you-contagious-with-covid-and-how-soon-could-symptoms-start-heres-what-to-know/

[moko]

The testing is a joke at this point. The US gov't moves as a snail's pace, so we need a judge to bring down rules.
Do you mean photoshop? That's always been the problem with requiring PCRs unless the location receives them from the source, like Hawaii was doing.

no. I mean authentication by the proctor with a green negative rest complete with the verifiable qr code

[biobook]

how would it do that? Is t the current recommendation only 5 days isolation? If you take the test after feeling mostly better wouldn't it still show positive even if isolation is no longer necessary?

Could you read the link I posted? I don't have time right now myself.  I think it answers your questions. 
Also, Ex-Gingi's situation is complicated by the fact that he doesn't have a date for when he first turned positive, if he ever did, plus he knows he was exposed to an active case since then.  (I think he implied that his daughter lives with him.) So he could have been negative with his initial symptoms, but subsequently got infected from his daughter.

[Lou Bob]

Second time covid was a breeze in comparison to the first. Had a light headache for a day and half. That's it. Waited 2 weeks to post in case I'd lose smell/taste again, but that didn't happen.
First time was early March 2020.
Only tested this time because I was exposed to someone who tested positive a few days before.

Is this basically what most people are experiencing round 2?
No vax