I have a family member with schizophrenia...HELP!!!?

My aunt is a clic case of paranoid schizophrenia, even though she has not been officially diagnosed. She is delusional, thinks people are poisoning her, thinks things smell like feces, urine, or cigar smoke...she has been ill for so long that she is now incoherent when she speaks, it's not just crazy but it's flat out illogical. She can not hold down a job, my grandparents are supporting her. I'm literally frightened for my life at times. Does anyone know how to get a mentally ill person evaluated against their will? WHAT CAN I DO I NEED TO KNOW!!!