How long after infection will an antibody test work? I have had 2 instances of suspected Covid infection, one where my friend who I had met outside for a walk actually tested positive. The latest was probably November 2020. Would I still be able to identify infection with the antibody test?

There's no simple answer. It really depends on severity of symptoms, length of the disease course, and immune system response. Some patients never produce detectible levels of antibodies, in others they may persist for years.

Patients who receive a negative antibody test after a suspected COVID-19 case might want to get a T cell test since that is another way to confirm previous infection.

https://www.fda.gov/news-events/press-announcements/coronavi...

Almost certainly yes.

The half-life of antibody levels has been estimated at 73 days. Good, commonly available antibody tests are quite sensitive, and they're accurate besides (99%), and time has not been enough of a factor yet to produce false negatives for this reason. In a year or two it might be.

As far as I'm aware, there's currently no evidence of people having "weak" antibody responses such that tests don't pick it up in a way that they fall below 99% accuracy.

The only time concern is that you need to wait 2-3 weeks until after you recover from COVID to ensure you test positive, as they take time to build up.

What is the population of people who are willing to get a blood draw for an accurate antibody test but haven’t been vaccinated already and can’t afford moderate flu-like symptoms for a day? I’m sure a small number of people like that exist but it’s not really worth carving out complex exceptions to vaccination rules (specifying which kind of antibody tests administered by who and when, etc.) to accommodate their preferences.

I've got a past positive Covid test. If that's not good enough, then why shouldn't every vaccinated person also have to go through the blood draw for an accurate antibody test to confirm their immunity? The vaccines are imperfect, just like all vaccines that have ever been created.

I already said why. Please reference my previous comments.

What are you even still trying to argue?

First you claimed antibody tests are inaccurate, which is totally false.

Now you're worrying that there are too many antibody tests...? Just like there are 3 vaccines, at least in NYC there are/were only 3 or 4 main antibody tests administered by the city.

It's super easy. Basically nobody's anti-antibody test the way there are anti-vaxxers, so it's actually a significant proportion of the population. And you know what? Being sick and useless for a day or two is actually a big impact on people's lives, I don't know why you're so uncaring.

It would obviously be beneficial if the commonly recognized antibody tests carried the same weight as a vaccine card, i.e. an equivalent standardized "antibody card".

Because minority rights.

>I’m sure a small number of people like that exist but it’s not really worth carving out complex exceptions to vaccination rules (specifying which kind of antibody tests administered by who and when, etc.) to accommodate their preferences.

You might as well be saying this about accessibility rules for disabled people.

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It has been shown that people who previously had Covid are more likely to have a worse reaction to the vaccine than those who hadn't. So when you combine that with the evidence that the vaccine actually confers no additional benefits to those people, it's exactly like you said: why make them suffer?