Provirus:
viral DNA that has been
inserted into the
host cell's
genome. It can remain
latent for long periods of time, becoming
active only when the cell undergoes
stress, or it can be permanently active once integrated.
HIV is normally always active (albeit sometimes at very low levels) when integrated, while many other virus species, such as
bacteriophages and
herpes simplex virus have lengthy latent
phases.
See also:
Molecular biology of HIV,
herpes