Lab Rats

We call it the Spree.
It started with a biowarfare plague.
Scientists all over the world tested possible cures and vaccinations frantically. Tested on animals.
Zoos were raided, wildlife reserves were stormed.
People were desperate.
By the time a cure was discovered, over half the world's population was dead.
As well as every single animal...
Animal testing no longer exists.
The tests haven't stopped.
Now they're just performed on humans.