At my Costco the 180 box is just under 40 with tax, and thats for the medium eggs. If you want large its $60 for the box. So this seems believable…
Signs of avian influenza include: birds dying without clinical signs; lack of energy; decreased egg production; soft-shelled or misshapen eggs; swelling or purple discoloration of the head, eyelids, comb, and hocks; nasal discharge; coughing; sneezing; incoordination; and diarrhea. The USDA has a resource with images to help identify discoloration and other clinical signs.