latent infection

A latent infection occurs when a pathogen, such as a virus or bacteria, enters the body and remains inactive or hidden for a period of time without causing symptoms. During this phase, the infectious agent is in a dormant state, often inside cells, and can stay there undetected. Later, it may reactivate, potentially causing illness again. Examples include herpes simplex virus, which causes cold sores, and varicella-zoster virus, which causes chickenpox and can later cause shingles. Latent infections can persist for years and sometimes relapse depending on factors like immune system health.