The probability of infection in this way is very low. As long as there is no wound sticking to the other person's body fluids, there is no possibility of infection. The so-called three-month exclusion means that most people will produce antibodies within six weeks after infection, but a few people will produce antibodies for a long time, so they can be excluded after three months. The accuracy of test paper is far less than that of peripheral blood test, which can only be used as a reference, and it is not possible to determine whether it is infected by a test paper.