I use the zapper for any viral situation. It doesn't seem to touch the big bugs. But as the bug bugs die the little bugs (viruses) jump off and give you the symptoms of a cold. Little tickle in the throat, runny nose, fever, etc. 10 minutes on the zapper and that's gone. If I don't have my Zapper available I do the tapping. It's the intermitant electrical shots that kill them. Somethimes I think the tapping is more effective that the Zapper. And I've never felt any electrical current at all.