How much saliva is required to pass hsv-1 oral herpes to another person?

Viruses are small!: Not much at all. Think of the size of a virus...Tiny, right? That's roughly the amount of saliva needed to transfer the virus. It's such a small amount that it could be an aerosol that you don't even see!

Tiny amount: Oral herpes is passed along from person to person via infected saliva. The amount of saliva required is small. The herpes virus is microscopic and can be passed along through simple means such as kissing, sharing silverware or lipstick, or drinking after someone else. It can also be spread through oral sex. As you can see, it's fairly easy to transmit; almost as easy as getting a common cold.