SV40 is an abbreviation for
Simian vacuolating virus 40 or
Simian virus 40, a
polyomavirus that is found in both
monkeys and
humans. It was named for the effect it produced on infected
green monkey cells, which developed an unusual number of
vacuoles. Like other polyomaviruses, SV40 is a
DNA virus that has the potential to cause
tumors in animals, but most often persists as a latent infection.