Answer:
A viral infection in a rabbit is like a viral infection in any animal: it's when the rabbit gets sick from a virus. Pet rabbit owners should learn about what viruses might affect their rabbits, and how they can protect them (sometimes with a shot, sometimes just by knowing the signs of a sick rabbit and knowing where and when to seek help). See the related questions below for more help.
Some viruses that affect rabbits include:
Herpes
Shope papillomavirus
Myxomatosis
Rabies
VHD