I need help deciding on becoming a Nurse Practitioner or a Microbiologist

My name is Arturo and I live in Mesa, Az. I have noticed that there is an illness that is going around in my city. I would like to know if someone here can help me. I am going to go to phlebotomy school and I also plan to go to nursing school at the community college I used to go to. I wanted to be an Adult Nurse Practitioner or a Psychiatric Nurse Practitioner. The one thing that is getting in the way is that I have speculation that the people who are sick in my city may have Candida Overgrowth. I want to be a PhD in Microbiology so that I can do research on the people who are sick, with the help of doctors of course. This has been bothering me for a while. I want to become a nurse so that I can pay my debt that I owe. I was told it was the better route for me. All I know is that if I become a nurse practitioner, I wont be able to do research on this subject. I can't warn anyone because I don't have proof. I need help deciding on a career or getting help for the people that need it. I know that nurses help people but I want to be able to prove this. It has not been proven in the medical field for GI tract Candida Overgrowth. It only has been noted with naturapaths. I dont think that Allopathic doctors would consider this as a disease. It has come to my attention that it needs to be taken care of and studied. What should I do?