When you buy "fresh" meat at the grocery store, you have no idea how long it has been sitting in that display case. However long it is, I can assure you that it has been sitting there a LOT longer than our meat did before it was vacuum sealed and frozen quickly to preserve the meat at it's absolute peak of freshness.

Freezing kills parasites and prevents the growth of microorganisms that cause both food spoilage and food borne illness so food that is kept constantly frozen will always be safe to eat. Only quality suffers with lengthy freezer storage. Once frozen food is thawed, these microbes can again become active so you should treat defrosted food as you would any perishable food.