A couple things. This thread has spun off into a comparison of apples and oranges. A classic zapper has very little voltage and very little amperage. There are so many "electric" devices out there now and each one must be studied on its own and not lumped together. Some devices could be potentially harmful but it is my opinion that a zapper does not fall into this category whatsoever. Also electro therapies can be very helpful to a large number of people. Rife technologies, Beck techonlogies etc are quite promising. There are more and more being studied all the time. If one is aware of the stunning work of Edgar Cayce , he even used electromedicine.
That said, i think the real benefit of using this technology lies in the utilization of frequency feedback and entrainment which is frequency specific communication to our cells and systems. It is this communication (entrainment) that can help create shifts in disease patterns. THis can be seen in devices such as the QXCI. If one is merely using electromedicine to anhilate pahtogens then the underlying cause of the disease goes unchecked. However if one creates harmony in the body, then dis ease cannont exist. This must be achieved at many levels...physically, mentally, emotionally and spiritualy. Its all about coherency. A total life plan ranging from proper diet and exercise to sound and congruent belief systems (based on life purpose) along with "helper" therapies that fit in concert are essential to achieve this harmony.