AZ last dose June, negative antibodies already

[Badgercity]

We are part of an ONS study where we have monthly antibody tests. So far my dh (AZ, dose 2 June) and myself (Pfizer dose 2 March) have been positive for antibodies. But this month DH has tested negative. Which is a bit of a shock and disappointing that they’ve waned so quickly.

Anyone cleverer than us out there that can shed some reassuring light on why? Especially as the kids currently have covid! Does this mean he no longer has vaccine protection?

I did see something saying 3 m for Az. Was like 5 m for pz.
Hopefully does as i had mine jun but even if were to get booster it wouldn't be till dec. It really is unfortunate for 40s who should have had pz due to risk and also by then it was clear az wasnt as effective.
However some relatives recently had covid after 2 doses AZ 65+ both did catch it but fingers crossed seem ok. And will have had second dose more like apr may time.

It’s concerning isn’t it? I’ll get a booster because I work in social care, but DH is 42 so that’s it for him now! I wonder if private boosters will ever become an option?

Anti bodies are only a small part of the bodies response.

www.npr.org/sections/health-shots/2021/08/28/1031287076/antibody-tests-should-not-be-your-go-to-for-checking-covid-immunity?t=1632404866599

He should still retain memory B cells to make more antibodies on reexposure and also memory T cells.
The body doesn’t continue to make antibodies when the antigen (covid spike protein) isn’t present. So depending on the half life of the antibodies and the original number you had some people will experience a drop to below detectable levels sooner than others. It’s likely he didn’t have that high an antibody titre to start with.
As you say your children currently have covid I would suggest he ticks the option when requesting a pcr test to test for antibodies. I think the government is now doing a scheme whereby if you get a positive pcr you can test your blood for antibodies around a month later. He should hopefully then see his antibody levels have risen again.
A lack of circulating antibodies does make it less likely he won’t catch it at all but doesn’t mean he will be seriously unwell as if he’d never been vaccinated.

Thank you, that’s interesting to read.

@JS87

He should still retain memory B cells to make more antibodies on reexposure and also memory T cells. The body doesn’t continue to make antibodies when the antigen (covid spike protein) isn’t present. So depending on the half life of the antibodies and the original number you had some people will experience a drop to below detectable levels sooner than others. It’s likely he didn’t have that high an antibody titre to start with. As you say your children currently have covid I would suggest he ticks the option when requesting a pcr test to test for antibodies. I think the government is now doing a scheme whereby if you get a positive pcr you can test your blood for antibodies around a month later. He should hopefully then see his antibody levels have risen again. A lack of circulating antibodies does make it less likely he won’t catch it at all but doesn’t mean he will be seriously unwell as if he’d never been vaccinated.

Thank you, that’s reassuring. It feels like we are back to last year, the same worries. But you’re right, he will still have better protection than he would if he had never been vaccinated. And of course, the chances of a healthy 40 something bring seriously ill have never been high.

theconversation.com/declining-antibodies-and-immunity-to-covid-19-why-the-worry-143323

I only posted this for the but about how long antibodies last but I see it says memory is also disappearing. The article was written last year and is about natural immunity not vaccines. I don’t know whether the findings of the study have been replicated since.

Dh and I are also doing the monthly ONS antibody (and swab) tests, and funnily enough did the latest just a couple of hours ago.

My 2nd AZ jab was mid April, dh’s (also AZ) about a fortnight earlier, and our last tests both came back positive for antibodies.

It will be interesting (or alarming!) to see the latest results in a few days.

@GETTINGLIKEMYMOTHER

Dh and I are also doing the monthly ONS antibody (and swab) tests, and funnily enough did the latest just a couple of hours ago.

My 2nd AZ jab was mid April, dh’s (also AZ) about a fortnight earlier, and our last tests both came back positive for antibodies.

It will be interesting (or alarming!) to see the latest results in a few days.

Fingers crossed for you! Of course, he may have had a false negative. We only just got the sample over the bottom line this time!

If you read the small print on the letter you get, it says something along the lines of "antibody tests are only counted as positive if you have the same number of antibodies as someone who was hospitalised with Covid".So you can have a negative test even if you do have some antibodies. It just means you have a lower number than the test threshhold.
Apologies, I can't find my last ONS test letter otherwise I'd explain it better (and with a more reliable information source!).

I did read that crumblelady though I must admit only a few minutes ago as today was the first time we actually fully read the email!

I’ve just got a very faint positive on an LFT, so that’s 3 of us down in the house. He’s bound to get it. Maybe it’s better he picks it up from us as we don’t seem to be very poorly so I’m guessing low viral load, than out in the community or even worse - at the university he works at!

I hope you are soon feeling much better. Please post and let us know how you all get along. Hopefully there is still sufficient protection. Lots are in the same boat as we see out this third wave and/or deal with it becoming endemic over the winter. Take care.

Those of you doing the antibody test - is it a yes/no result or do you get a value so you can understand what the decline rate is?

We are also part of the same study.

After one Pfizer I had antibodies

Granted closer to his jab but after one AZ my DH did not- read a a lot about it and @Aposterhasnoname link very much what he found-lots of things impt and the “antibody is the only thing” a bit simplistic.

We now have had both and both tested positive for antibodies and have done for months. @roses2 yes- it simply says positive or negative

DH and I do the VirusWatch study. I get a result but unquantified.
After one AZ in January (2nd April) I was negative but tested positive 10weeks later up to July.
I then got covid, quite badly but DH escaped.

I was curious to know how many antibodies we had, I know about T cells etc but you can't test for those and I wondered why I was still able to get covid so badly in spite of having antibodies.
My test promised to show both vaccine and infection produced antibodies but in fact it didn't. I just got a total and it only measures up to 2500U/ml

Above 0.8U/ml counts as positive.
DH had 2150 and I had >2500.

So I guess it shows that DH was well protected from his 2nd vaccine dose in April.
I also suspect that my vaccine antibodies before covid, although positive, were very low. I am immunocompromised.

Try not to worry.

I'm 48 , last AZ jab in June. I currently have Covid, caught off my son.

It's not been pleasant, but still not as bad as the flu. Sounds like your DH is younger than me, plus my BMI is around 30, so hopefully he's at little risk.

I knew with Covid it would be when, not if, with 2 kids at different secondaries in a high Covid count region.

I had my first negative antibodies test (ONS study) on 30th August. They had previously been positive following my second az vaccine in May. Some of these responses have explained immunity etc well and settled my mind a little.