What do you thinks are good ideas for a Zombie story?

A solar explosion on the sun starts a severe solar storm that rips thorugh the ozone, releasing unhealthy amounts of radiation into the air. For most of the world the radiation mutates them into your zombies. HOWEVER, there is an EXTREMELY rare gene that only your characters and the people at the camp have, and they survive and are unharmed. The people at the survival camp send out searchers to find these teens, therefore taking them in.