HI Claythrow, I think sometimes chelation can cause someone to be more suseptible to infections. Not only because of the chelator DMSA itself, but also because of the movement of metals and the stress of chelating.

Also, when you take a break from chelating, sometimes you may get more of a build up of mercury during that time. Because mercury is still continuing to leak out of you. This is why some people who think they might be cured, stop chelating prematurely and wonder why later on they feel sick again. It's usually stored mercury that still hasn't been sufficiently chelated out and it is still leaking out and if it's not being continually picked up by chelating agents, then you may notice the effects if you have a long enough break.

Just some thoughts.