6 Ways to Die — R. Mac Wheeler

Alcoholic parents treated Margarite as an unwelcome stranger, then left her at fourteen with her thirty year old autistic brother. At sixteen, things really sour, thanks to her brother. A medical researcher, Reggie engineers the ultimate plague. Fanatics seek to control him. The government pursues them as terrorists. Margarite witnesses ruthlessness, compassion, and competence she couldn't imagine from her brother, but the world needs a miracle. The best she and Reggie can do is wing it.