It's when the virus stays hidden in your body, and you won't show any symptoms . But they can come out again and cause problems. For example, having an HIV infection makes it easier for a person to get pneumonia. Having an open herpes sore makes it easier for bacteria to opportunistically infect that area of the body. 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.