Multistate Outbreak of E. Coli O157:H7 Infections Linked to Romaine Lettuce
cdc.gov
cdc.gov
I think it more appropriate for most people to eat seasonally-appropriate vegetables during the winter months, than to get a little lettuce from thousands of miles away. Winter squash, carrots, apples, and many other food products store very well in root cellars [1].
[0] http://www.visityuma.com/agritourism.html [1] https://en.wikipedia.org/wiki/Root_cellar
My point is that it's more efficient to eat locally-stored produce than to ship lettuce from Yuma to Maine in the winter.