Costco and Trader Joe’s are limiting the number of eggs customers can buy because of a shortage caused by the avian flu.

Trader Joe's has added a limit to how many eggs shoppers can purchase at all of its stores as bird flu shortages increase. Why it matters: The bird flu has affected at least 23 million birds in the last 30 days,

Egg purchases will be limited for Coles’ customers after a new outbreak of bird flu was discovered. The supermarket giant will maintain purchase limits on the number of cartons per person, which were first imposed last year after an initial outbreak of the virus.