I think the cure for social anxiety is gradual exposure to the kinds of social situations that produce social anxiety. As these situations become more familiar I think there is a good chance that they will cease to be the cause of anxiety. I think the anxiety results primarily from the uncertainty of the situations.
There are numerous medications that can be used to reduce social anxiety as well as certain other relaxers that can help a person in this situation, if the problem is severely effecting your life you can seek treatment from a therapist who can help work with you, so overall I believe there are many cures for social anxiety if you actively seek them out.
Social anxiety probably can not be cured but perhaps it can be modified by changing the expectations we have that every person needs to mingle easily with large groups of strangers. The person with social anxiety is very much entitled to pick and choose who he or she will relate to and in what circumstances.
I do not believe that there is a cure for social anxiety. I think that such a mental condition is just something that some people are going to have to overcome on their own. But there are a lot of ways they can get help for their social anxiety. Sometimes medications can help.