It seem to be the bodies natural reaction when it need to adjust to new energies. I remember midweek being impressed with how well my throat started to open as energies cleared. Same night I found myself with the flu. Most of all it feels like there is some major rewiring of internal stuff going on. I do believe that at some point in spiritual development you gain the ability to no longer get sick, and the sickness merely is the bodies way of adjusting to your development. So though I will appreciate it on the other side, I am cool with it only happening when necessary