As well as via food, E. coli from a variety of sources can also cause urinary and bloodstream infections. While one study suggests a large proportion of resistant E. coli isolates causing bloodstream infections in people could emanate from livestock produced for food,[72] other studies have since contradicted this, finding little commonality between resistance genes from livestock sources and those found in human infections, even when examining plasmid-mediated resistance.[73][74][68]