Tranpsose it to D--then the change will be D to Am(or C, if you are so inclined)--just move all the chords up one step (c to D, G to A) and you'll have it--

This song doesn't have any of the qualities of the blues--no swing rhythm, none of the measure structures, either 12 or 8, non of the call/response repetition, and no blue notes--and, further more, if I remember, it changes meter--the first part being an odd straight 6(Hush little baby don't you cry)--the "All My Trials" being in a more conventional 4--

Now,admittedly, I have never heard a folkloric version, which would likely be different, but I wouldn't know what way it would be different--