It looks a bit like aster yellows but I don't see yellow, stunted or spindly leaves on the plants in the photos. Before I give you the info on aster yellows please know that another reason for distorted flowers may be herbicide drift. So before you pronounce, you might want to determine if anyone has sprayed an herbicide near where your coneflowers are growing. On a windy day, it can spread far.

If it is aster yellows, the plants are doomed and to prevent other plants in your garden from getting it, you need to remove and destroy all affected plants. There is a huge list of plants that can contract this disease so the sooner you remove these plants the better. This U of WI Extension web page on aster yellows can provide you with more information about the disease which is usually transmitted by infected leaf hoppers (and guess where they get infected?).