So, if we were to say take a skin sample of a suspicious rash and look at in under a microscope and see squigglies, the only way we would know those are Lyme squigglies would be to send out our sample for testing.

If the host had disease symptom that helped distinguish from similar looking organisms that was a big clue.

In the case of more normal bacteria they might culture them. Many bacteria form a very distinct appearance growing in a petri dish.

Gram staining would help narrow them into gram negative or gram positive categories.

I think there is a certain amount of guessing involved also.

LOL, yup.

if you look at the old syphilis studies in the archives here you can get an idea.

If something is pulled from a EM rash or lesion then it's much more likely to be the cause of illness, right? Then also if everyone with a certain illness has the same uncommon bacteria then that's evidence too.

sooooo... how many older syphilis studies actually found lyme and didn't know it? And how many of us lymies have syphilis or leptospirosis and don't know it? (the tests cross react sometimes and not all syphilis has classic syphilis lesions.)