How do I get that "first" job in my future career without having any previous relevant professional experience?

I recently graduated with my master's in public health in December (3.98/4 GPA), but I'm having a hard time with the job hunt. I have been employed since 2011 in retail and most recently for the past 4 years, as a medical assistant. I live in D.C. so jobs in this field are not scarce but every job (including entry level) I do come across always requires 1-3 years of prior experience.

I've been trying to network as much as I can with alumni but that is going slowly to say the least. How do I get that first career job when my entire work history until now has been unrelated to my graduate degree? All the experience I do have is from school and not in the professional world. Many people I have spoken to have said that I can do much better than starting at an entry level job with a graduate degree. I find that hard to believe when even the entry level jobs don't call me back.

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