HI. Best treatment I've ever used was a combination of echinacea for three days with cranberry capsules for three weeks. That cured it.
I don't know where you live, but the echinacea I used was purchased in France and was much more powerful than that here in the U.S. Local echinacea never did anything for me- it is very, very week. Those huge capsules must be full of fillers or something. In europe the herbals are much smaller and yet more powerful. If you know some way to get some of theirs, go for it.
Here at home, I've used unsweetened cranberry juice and used the usual remedies to boost the immune system, like Vit C, garlic, etc.