Sorry about ur brother. Hope he is well quick. Were his white blood cells elevated?
That would indicate an active infection. I was diagnosed with rocket mountain spotted fever 2 years ago. My level 3x positive. I got better with 21days of doxycycline. Then worse again. I'm still trying figure out what is wrong with me.

funny thing....when they ran the rocky mountain test again, I had no antibodies, so WHICH TEST WAS WRONG?
II don't know any one on here yet, don't know who has medical backgrounds or what. I am not the sharpest tool in the shead, but have him go to an infectious disease specialist.
If it is from a vector, then they are most likely to find it.