health

In most types of viral infection, the immune system clears the virus from
the body within days to a few weeks. But some viruses cause persistent or
latent* infections, which can last for years. In these cases, a person may
get infected and seem to recover or may not be aware of being infected
at all. Then years later, the illness occurs again, or symptoms start for the
first time. Viruses that can cause latent infections include herpesviruses,
Hepatitis B and C viruses, and HIV.