I'm looking for an expert opinion, having scoured the internet and come up empty. I don't believe I ever had Covid. I got my second Pfizer shot in April. I did have a mild immune response (a day of body aches, and a swollen lymph node for a few days, in my neck above the vaccine site).
Planning to travel in the next few weeks, and seeking some reassurance that the vaccine "worked", I took the T-Detect test[1] last week. It came back negative for adaptive T-Cell response. Now, before anyone attacks me for getting this test for the wrong reasons, I'm just trying to gather as much information as I can. From what I've seen in online chatter, it seems that most people getting this test are getting it to justify avoiding getting a vaccine; I got it for the opposite reason. I went in knowing what it says in the FDA FAQ[2] about the test:
> "...the meaning of a positive result in individuals who received a COVID-19 vaccine is unknown."
It also says:
> "The meaning of a negative test result for individuals that have received a COVID-19 vaccine is unknown."
But obviously, it would be better to have a T-Cell response than not to have one.
I know that some antibody tests only show antibodies induced by infection, while specialized others show those induced by the vaccines. But would one expect the same differentiation from a T-Cell test? The company is entirely silent on the subject. I'd like to form some rough risk assessment on whether a negative result is an indicator that any post-vaccine immunity I had is reduced or gone.
Thanks for reading.
[1] https://www.t-detect.com/
[2] https://www.fda.gov/media/146480/download
Pfizer vaccine is roughly 40-60% efficacy against delta variant infection. But it should prevent hospitalization. “Mild” infection still means you could be out for many days or weeks.
Check the positivity rate for the areas where you’re going. If it’s high and increasing I would cancel, because you might run out of hospital beds. If it’s declining then mask up and be conservative.