U.S. food safety: What to know amid outbreaks
A bird flu outbreak is affecting several dairy herds across the U.S., and a federal recall is affecting more than 16,000 pounds of ground beef sold in Walmart stores in 11 states due to possible E. coli contamination. Michael Worobey, head of the Department of Ecology and Evolutionary Biology at the University of Arizona, joins CBS News to discuss the state of food safety in the U.S.