How to get 5 biohazards?
I have never even got 4 bio-hazards before.
What's required to get 5 bio-hazards when you win?
The number of Biohazard symbols is based on your score. A score of 30,000 is required for 4 stars. A score of 100,000 is required for 5 stars.
Score is based on several factors but the two main factors are the final cure percentage and the difficulty level. For 100,000 points, you need to be playing on brutal and to win the game with the cure percentage at less than 10%.