The standard zapper can definitely have some effect but I would not count on it as a cure.
There are several reasons for this and one is that a standard zapper is sort of "luck of the draw". Standard zappers are not highly accurate and each unit will vary from others of the same model due to component tolerances.
So, if you use one, you might be lucky enough to get one that has just the right frequency and therefore good results. The other 95 to 99 percent will have other frequencies that may be helpful but not fully effective.
However, I will add a footnote here. From what I have seen, many viri are easily destroyed with electric pulses and herpes may be one of those. As an example, almost everyone who uses a zapper at the first symptoms finds that the zapper can quickly dispatch a cold or the flu.
I used to have frequent cold sores from herpes simplex but they have never come back since I started zapping in 2001.
My personal opinion is that if I had nothing else, I would use a regular zapper for it and hope for the best.
Years ago, I sent out surveys to many zapper users and found from these that zappers with 2 frequencies work better than a zapper with on frequency. This is why dual frequency zappers became standard until the arrival of multi-frequency zappers.