Let's say that once I'm vaccinated I try the rapid serological test and the result is negative. My question is: let's admit that the reliability of the test is 100%; does it mean that the vaccine didn't work? Or is it more probable that the working mechanism of the rapid test does not catch the antibodies?


1 Answer 1


I have found on the internet (see sources below) that the answer is in general no, for two reasons:

  • the serological test must detect the antibodies related to the Spike protein, and this condition is not respected by most of rapid tests. In particular, some look for the nucleocapside protein which is contained inside the virus (not on its corona like the Spike protein) and it is not induced by the vaccine;
  • the tests are actually very low in reliability.

This result is meaningful especially for a study in a large number of people: other kind of tests have to be performed. Indeed, specific tests which look for the vaccine induced Spike protein are used.


https://www.focus.it/scienza/salute/dopo-il-vaccino-come-capire-se-si-e-immuni-alla-covid https://iris.paho.org/bitstream/handle/10665.2/53057/v44e1492020.pdf?sequence=1&isAllowed=y

Hope this could help. Bye

  • 1
    Your self-answer is actually fairly correct, but to stick to the rules of this SE site, you should add some references supporting it.
    – Fizz
    Mar 6, 2021 at 23:49
  • Right. Thanks for the comment. Mar 7, 2021 at 19:58

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.