I have heard that most start with treating Borrelia because it creates the most immune disfunction, so even if a co-infection is a bigger problem for you in general, you might get more bang for your treatment buck if you weaken Borrelia first. Not sure how legit that is, just passing along the reason I have heard for why most people seem to start with Borrelia treatment.
That said, some don't start with the infections at all, and rather work on the gut and detox pathways first, but that's not what you asked about
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