The Adder Notes is a file that can be found in Resident Evil: The Umbrella Chronicles.
Transcript
This small, venomous snake was secondarily infected by the T-virus, leading to a mutation with an enhanced ability to attack prey. It has the ability to multiply with incredible speed, and its already-potent venom has further enhanced by the effects of the virus. The adder's bite also carries with it the potential to further spread the T-virus.