Be careful of avalanches when trekking to Annapurna Base Camp, especially the part near Deurali before Macchapurcharre Base Camp. I have to pass by 3-4 previous avalanches on the route. You can get the news of avalanches from the towns along the way.
Avalanches are an inherit danger when climbing, especially at high altitude. Avalanches are not rare either, and are quite common one some of the largest mountains.
Well, from what I have heard, to try and survive an avalanche, you want to try and fight your way to the surface of the snow and not get caught up deep in the snow.
don't go trekking in the afternoon when there is danger of avalanches. Three germans died this year, ignoring information given by the locals in Machhapuchhre BaseCamp.