Kissing is an oral act. Oral sex is when a person's mouth touches another person's penis, vagina, or anus. This seems less risky than penetration for getting STDs, but it can transmit certain diseases. It may be a form of secondary contact . Vaccines help your immune system get ready for an attack by a particular bug.
Some viruses can become latent .
You have to wait out the window period of 6 months before the test will work.