Are cats carriers of parvo?

Parvovirus - Wikimedia Commons file
Author: Nephron

Yes. "Parvo" is short for parvovirus. The feline panleukopenia virus is a member of the parvovirus family. The feline panleukopenia virus causes the infectious disease feline panleukopenia which is also called feline distemper (a misleading name). It is sometimes referred to as panleuk.

The feline panleukopenia virus is highly contagious and "is present wherever there are susceptible animals" (1). Wild cats, mink, ferrets and monk serve as a reservoir.

Cats that are immune to reinfection can shed the virus for weeks. There are asymptomatic carriers (infected animals with no symptoms). This causes repeated exposure in a group of cats. This can actually boost immunity in cats that are already immune through antibodies.

Kittens can be infected before birth. For these kittens mortality rate is 90%. It can cause brain damage in kittens.

Read more: Feline Distemper Symptom and Panleuk or Feline Distemper.

Note: (1) Cat Owner's Home Veterinary Handbook ISBN 978-0-470-09530-0