Herpes zoster, the virus that causes chickenpox and shingles (it's also called varicella), does respond to Zovirax, but I've never seen Zovirax used topically for shingles. It's very expensive in cream form and doesn't do anything to reduce the long term consequences of shingles by itself. I could see it maybe being used in combination with an oral antiviral if money was no object and you wanted the sores to heal a little faster, but the benefits are minimal compared to the cost of the stuff. If I had my druthers I'd rather pay for oral Zovirax (acyclovir) and a strong pain pill and wait a couple of weeks for the darn things to heal than waste my money on a cream that may or may not help. JMO.
And you can get chickenpox from touching the rash of someone who has shingles (or from touching something which has touched the rash...), but you can't catch shingles from someone who has shingles.
Herpes simplex is a whole 'nother animal, but it can also be treated with Zovirax. Once again, I never prescribe the cream, only the oral, for two reasons. One, the oral is cheaper and works better. Two, herpes simplex is spread by skin to skin contact and can spread from one part of the body to another. So why would you give a patient a cream to apply with their fingers several times a day? The virus will get on their fingers... and then maybe in their eyes if they rub them (herpes in the eyes can cause blindness) or cause recurrent infectious rashes on the fingers themselves. This is called herpetic whitlow. It's rare but can be a major problem since people with herpes can shed virus without symptoms. So people with whitlow can shed virus from their fingers asymptomatically and can contaminate anything they touch with the herpes virus. Scary, huh?
![Confused :?](./images/smilies/confused.gif)