@Velsy She was already used so she probably thought she would have to let herself be used more in order to stay safe...especially for her child.
Well, they mentioned the T-virus earlier...though, I don't see why it would be more dangerous at night. As I don't recall zombies being more dangerous at night in Resident Evil...unless he just means the danger low/no visibility adds. Or author is just combining different zombie games and movies...
