Covid is found in many ways. A week after the onset of the disease, antibodies appear, which can be detected and confirmed. There is also PCR, which catches the virus in the nose. These tests are done in a laboratory.
There is also a so-called antigenic test. It looks like those familiar two-strip home tests. He also finds a virus in his snot, but the result can be obtained even at home in 15 minutes.
For some reason, people are especially worried about such a test before vaccination. The people are very much afraid of being sick and vaccinated at the same time.
I explain what is wrong here
Even if you have an invisible covid inside you, which you do not feel, then it does not interfere with the vaccine in any way. Therefore, there is no point in looking for it.
The antigen test is simple and quick, but has low sensitivity and specificity. At least compared to PCR nasal swab.
This means that if you are not sick, and patients do not cough on you at home, then a positive antigen test does not mean anything. Now, if it were negative, then in such a situation it would be possible to say that you are not sick.
And if you got a positive antigen test in your healthy little one, then no conclusion can be drawn. These are the pies.
Each situation has its own sequence of actions. If you decide to go for vaccination, you feel fine, did an antigen test and got a positive result, then in the next two days you will have to do PCR to confirm the antigen test. That is, you wasted your time and money.
So what else is attractive about the antigen test?
Well, due to its low sensitivity, oddly enough, it gives a more realistic picture in terms of the infectiousness of a sick person.
That is, roughly speaking, a person is contagious for about a week (two days before and five days after the onset of symptoms). The antigen test is usually positive around this time. Such a person will be immediately sent to quarantine. And they will do the right thing. Because the dude is really contagious.
In the case of PCR, things can turn out differently. PCR is very sensitive. In different laboratories, it is calibrated in different ways and taken into account in different ways. A very common situation is when a person quietly fell ill, is not at all contagious, but his PCR will be positive. And it is completely undeservedly declared contagious. It's offensive.
In short, don't do unnecessary tests. There will be fewer problems.
