I too heard privately from the concerned chemist. I responded to him 
privately, but think it is not inappropriate for this thread: 

I would rather have had a two-three week possibly unnecessary course of 
doxycycline than the three years of antibiotics that I ended up with, due to 
ignorant doctors and my not having tested positive until ten weeks after a tick bite 
and resultant symptoms.

Leslie Starr
Baltimore & Port Republic