Ok i'm not very good at this, but i'll give it ago. Rowena has been living with her aunt and uncle in Australia since civilisation fell. She has no idea what is happening out there, she only knows that since her uncle was attacked by a wild dog something has been attracted to his blood and it comes round every night trying to get in.
Her aunt traders her to the road gangs that have the intention of rounding up survivors and expermenting on them or making them members of the road gangs or both.
When they do experiment on someone it makes them violently ill and mutates certain parts of their bodies, it different for everyone. The drug they're given is only known as serum. Only a few survive long enough to show signs of mutation, which usually starts to show up around the 3rd use, for some it's a lot sooner.
There is a cure, but the doctors and scientists are reluctant to hand it out to their experiments, hording it in case the day comes when they need it.
Now one of the Guards (nicknamed Goggles - i've not given him a real name yet) is in charge and demanding that all surviors brought in be infected with serum and then given the antidote to see what effects it has.
Rowena has already stolen a cure and injected herself, but it was for external contamination only (in other words, their is two kinds of cure, one for those with serum injected direcly into their blood and one fo those that contrart the diease threew the skin, she's taken the one for skin contamintion, but she was injected with serum) the effects of this are unpredictable.
There is an on going war between the surviving humans and the creatures stalking the night, and Rowena and anyone else that survives contamintion is going to be used as as weapon agains these creatures.