Spam has become a real problem for many, but luckily there is an efficient way to get rid of it.
Here is a fully updated guide with the latest information to show you how to stop the spam in Google Analytics with 2 filters.
Here is a good article published an article on MOZ talking about this issue and some common mistakes you should avoid. I hope you like it.
Spam drives me nuts, and this article I found to be really helpful.