Anthem Leak - How do I find out if I'm affected?

Recently, Anthem (A health insurance company somehow associated with Blue Cross Blue Shield and potentially other insurance providers that I am unaware of) was the victim of a large data breach. I've seen reports that Anthem had a vulnerable database with the records of 80 million customers. I've also seen that they haven't informed many of those individuals.

How can I or my family have been affected? Or do I just have to sit around and wait until someone tells me?

On a similar note, how do I take precautions if I have been affected? If my medical information was stolen there isn't much I can do is there? For passwords I can change them and not use the same password (which I don't), but is there anything else I should be thinking about?

Thanks!