CDC Identifies Significant REP Strain of E. coli Causing Outbreaks Linked to Leafy Greens
Using whole genome sequencing (WGS), the U.S. Centers for Disease Control and Prevention (CDC) has identified a reoccurring, emerging, and persistent (REP) strain of Escherichia coliO157:H7 that was implicated in a significant foodborne illness outbreak linked to romaine lettuce in 2019. The strain, REPEXH02, is believed to have emerged in late 2015 and caused multiple outbreaks from 2016–2019.
In the article classifying REPEXH02 as a REP strain, CDC concluded that 58 percent of recent E. coli infections can be attributed to vegetable row crops, mostly leafy greens. The strain of E. coli in question was found to be the cause of an outbreak in 2019 associated with romaine lettuce grown in the Salinas Valley region of California, causing 167 cases of illness across 27 states that resulted in 85 hospitalizations. Additionally, a late 2020 outbreak also linked to leafy greens sickened 40 people in 19 states, resulting in 20 hospitalizations and four cases of hemolytic uremic syndrome (HUS).