Maybe nobody cleaned it up? Supposedly it can’t live long outside a body an sunlight will kill the virus.
Viruses are remarkably diverse.
Some are extremely durable. The smallpox virus, for example, may remain contagious in clothing for years.
Others, such as the AIDS virus, are very fragile. Luckily. Which is why it requires really, really close contact to contract the disease. The virus dies almost immediately outside the body.
"Die" isn't exactly the right word, since viruses aren't really "alive."
Depending of course on how you define "life."
I've seen crows eat sick....