Escherichia coliO157:H7 in Feral Swine near Spinach Fields and Cattle, Central California Coast1

Abstract
We investigated involvement of feral swine in contamination of agricultural fields and surface waterways with Escherichia coli O157:H7 after a nationwide outbreak traced to bagged spinach from California. Isolates from feral swine, cattle, surface water, sediment, and soil at 1 ranch were matched to the outbreak strain.