I think MPHs are a waist of time for multiple reasons. The first being many major universities' mph programs are diploma mills for MDs or residents so the quality of education is poor, especially at the big names in pub. health e.g., johns hopkins, harvard, berkley etc.
If you cannot get into a PhD program today, I would suggest getting a master's degree in a math/statistics/science type discipline. Do NOT get a master's in something like nursing or kinesiology or nutrition. These majors are for people who cannot do science and they generally end up in very remedial schools, if they choose to transfer over to pub health later in life.
I know a few Dr. PHs and they are very smart but have very limited skill sets. They have not brought in any dollars from research grants at least not from NIH which is very important to do especially if you want promotions and tenure. Dr. PHs are more analysts than anything else. They do a lot of consulting and generally teach data analysis courses to MPH students, if they have to teach at all.
Pub Health is one of the best disciplines in academia, if you are good at what you do. You have opportunities to help people at a mass level and the opportunity to earn a very comfortable salary.