>- 30kHz HK zappers and one is the 727Hz zapper ... 2-3 cases with very strong flu/cold, which were resolved in just 1-2 hours with Zapper, and maybe 10-20 cases with no effect
I believe that this supports much of what I have said over the years. Single frequency zapping is just not as productive or effective as using multiple frequencies.
Also, what I have found is that the earlier that you catch a condition such as a cold or flu, the better the chance of stopping or reducing it.
As a last note, I also find that, at least for me, zapping a few extra times can help.