Antibody test AFTER a vaccine

[TheGoodEnoughWife]

Hi, has anyone tried a at home antibody test after they have had the vaccine?

I was hoping for one where you drop the blood in and it tells you within minutes (similar to a pg test) although most I am finding online you send away.

I know I would need to leave it maybe four weeks after the jab?

I would just be interested to know if I have any coverage after first jab last Saturday!

Yes, DH did exactly this after having his shot (Pfizer). After the first one it showed negative until 16 days or so. There was a faint positive after 18-20 days. After the second shot it showed a strong positive after just 4 days. He got his tests from the pharmacy. It's reassuring to see the results (and I find it hilarious that for the first time, men are staring intently at tests hoping to see the second line)

That's interesting @User594022452
I think I will get some and try it!

Just incase anyone is interested!

I did a send off blood test one and it came back positive for antibodies after 3 weeks 2 days. Will check again after next jab but that isn't until May.

I am really pleased!

Which one did you use?

Complication is - antibody tests can test for antibodies to different parts of the virus protein.

Antibody tests often look for antibodies to the virus N protein.

Most of the vaccines induce antibodies to the virus S protein (the spike protein).

This one is s protein. Used to detect either from infection or vaccine.

This was an Immunity Tracker from Testing For All.

I'm about ten weeks post dose one (and 24 hours post dose two, woohoo!). I'm doing monthly antibody tests as part of a research project.

The most recent result I have reads:

N-antibodies: Not detected
S-antibodies: Detected

Apparently if you've had an infection, you're likely to show both N and S antibodies, but the vaccine induces just S-antibodies.

I don't know what N and S stand for in this context.

I had Pfizer, but the info leaflet from the trial organisers doesn't specify that there's any difference.

@User594022452

Yes, DH did exactly this after having his shot (Pfizer). After the first one it showed negative until 16 days or so. There was a faint positive after 18-20 days. After the second shot it showed a strong positive after just 4 days. He got his tests from the pharmacy. It's reassuring to see the results (and I find it hilarious that for the first time, men are staring intently at tests hoping to see the second line)

Did he do them every day after the second shot ,but didn't get a positive until Day 4? That suggests that the immunity from the first shot hadn't lasted. Or was it that he didn't even try until Day 4? How far apart were his doses?

Interesting @Motorina
Mine doesn't say about N antibodies only S.

I really don't think I have had Covid-19 but of course you never know for certain.

@Motorina

I'm about ten weeks post dose one (and 24 hours post dose two, woohoo!). I'm doing monthly antibody tests as part of a research project.

The most recent result I have reads:

N-antibodies: Not detected
S-antibodies: Detected

Apparently if you've had an infection, you're likely to show both N and S antibodies, but the vaccine induces just S-antibodies.

I don't know what N and S stand for in this context.

I had Pfizer, but the info leaflet from the trial organisers doesn't specify that there's any difference.

S is the spike protein - the spiky bits that stick out of the virus. It's easily seen by the immune system because it's right there on the surface of the virus. All of the vaccines used in the UK at the moment train the immune system to recognise just the spike protein.

N is the nucleocapsid protein - think of it like the polystyrene peanuts you get in packages sometimes, it protects the RNA inside the virus (amongst other things). When you are infected with Covid your cells will be producing loads of these peanuts to package the RNA so the immune system recognises it as foreign and produces antibodies against it.

If you've had covid recently then you should have detectable levels of antibodies to both S and N. If you're vaccinated and haven't had covid then you'll only have antibodies against S.

@QueenStromba - thankyou. Clear and interesting.

How reliable are these tests? I'm interested as I had steroids into a joint just before my vaccine. At the time I didn't realise my vaccine would be so close. I'm on immunosuppressing medication generally, so it would be lovely to know if it worked.

I did an antibody test for UK Biobank research three weeks after my Pfizer jab. The test was set up to show two types of antibodies or nine, I forget the labelling. I was pleased to see I had the longer lasting type. They do warn you to keep taking all the usual precautions.

@OhYouBadBadKitten

How reliable are these tests? I'm interested as I had steroids into a joint just before my vaccine. At the time I didn't realise my vaccine would be so close. I'm on immunosuppressing medication generally, so it would be lovely to know if it worked.

I am on a Biological for psoriasis and did a Roche post vaccine antibody test 3 and a half weeks after my first jab. This test gives a quantitative result for antibodies. However, I got the result and although I am positive for antibodies the number is very low. 5.1U/ml. The range is 0-2500. The problem is interpreting the result. The more I research the more I realise this result is not telling me anything much about my level of immunity and it was probably a waste of money.

That's the sort of thing that concerns me, so thank you lazymum. I'm better off I think living in cautious happiness that I probably have some protection, rather than risk fretting about low numbers.

None of us are scientists. And from what I read the body does all sorts of other stuff (T cells etc) to protect you. Initially I was pretty upset with such a low number but I’m not going anywhere or doing anything at the moment anyway. Before my next jab I think I will contact the consultant and maybe miss out a dose so maximise the time for a good immune response. My condition is well controlled so I can’t see a problem with this.

I see what you mean @lazymum99, I have had a better read up now and found this interesting...

The site does give a general breakdown of how many antibodies were found in people but it also says this - that ANY antibodies found means your body has reacted to the vaccine and so they expect some protection because of that.

So I think the test is helpful to show whether there has been any immune response but the levels should not be taken too seriously.

I hope so!

@Motorina

I'm about ten weeks post dose one (and 24 hours post dose two, woohoo!). I'm doing monthly antibody tests as part of a research project.

The most recent result I have reads:

N-antibodies: Not detected
S-antibodies: Detected

Apparently if you've had an infection, you're likely to show both N and S antibodies, but the vaccine induces just S-antibodies.

I don't know what N and S stand for in this context.

I had Pfizer, but the info leaflet from the trial organisers doesn't specify that there's any difference.

I'm doing that study as well - is it the Virus Watch? My results 5 weeks after 1st dose of vaccine were N- antibodies Not detected S- antibodies Not detected.

I am hoping the next test will show some S antibodies, it will be 9 weeks after vaccine.

I take immunosuppressive drugs but a low dose. My Rheumatologist was unconcerned about the lack of antibodies and thinks I will still have some protection.

Out of interest Phym did you have any side effects after having the vaccine? I’m just wondering about the coloration between antibodies and vaccine side effects.

No nothing other than a sore arm, I did wonder. To be fair nor did DH who tested positive for S antibodies.

I had a slight sore arm and a bit of a headache the next day. None of the more extreme reactions people speak of.

@Phym yes - viruswatch.

I tested hubby with the at home antibody test. He had covid last March and had developed antibodies but like became fainter after few months. I checked again the day before his vaccine and it was totally blank. 3 weeks after his jab did it again and it came back with a super strong response.