As avian bird flu continues to spread across the country, six grocery stores are limiting how many eggs their shoppers can purchase. Here's what we know.

Some grocery chains are leaving the decision up to individual stores or regions, while others have implemented restrictions at all stores. Trader Joe’s is allowing customers to buy one dozen eggs per day, while Walmart is limiting purchases of bulk 60-count egg packages to two per purchase.

With prices rising rapidly, some of the nation’s biggest grocery store chains — including Trader Joe's, Walmart and Costco — have begun rationing eggs.