HELP! Wyld Wyrm is popping every time!!!

Hello Warmane people! I have a big issue that I hope someone can resolve me. Because it's veryu frustrating: I've taken the fly from dalaran to Dun-Niffelem, so the gryphon passed throught the Wyrm blue drakes, and a yellow alert popped out "Wild Wyrm swipes at you with his claws!". Now every time i go in Northrend (in EVERY places, Dalaran, Icecrown, Wintergrasp, ecc..) this message pops out every 3-4 secs. Some people can help me? I will be very glad!!!

I've also tried to log out, delete cache, change pc but nothing happened!