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?
If you want to go into research you need a PhD to do much more than be a bench rat.
what do you mean by bench rat?
Someone who does the lab work for experiments that the PhDs think up.
Go into the career that you find most personally rewarding...not one that you think will yield you the most money (you said that you needed to pay back a debt). Sounds like microbiology is your true interest.