small blister in a circle

[hggirl]

Several times a year for several year I get several small blisters on the back of my leg. they are in a tight circle about the size of a dime or nickle. Most often at stessful times of the year. It is always in the same spot. It is very tender, and even burns sometimes. Alcohol doesn't seem to help witch hazel helps some. I am just fearful of having something contagous. I am single again and wouldn't want to harm anyone.
Help please

[BoBerly]

I also have the same thing.  Comes the same time every year and itches like crazy.  My mother said she had it and now my daughter gets the same thing on her arm.
I would be interested to know about this.  I am assuming it is some type of Herpes like in the shingles family.

[tmv]

ring-worm (a fungus) can grow in circles. Do you have cats? It treated with a topical anti-fungal.