Every autumn since 2017, romaine lettuce has been blamed on E. coli outbreaks in the U.S., with hundreds of people sickened.
This year, health officials are investigating 3 separate outbreaks of E. coli with unknown origins. All of the outbreaks involve strains of E. coli that were linked to romaine lettuce in previous years.
In the first outbreak, at least 12 people in 6 states were infected with E. coli, including 5 people who were hospitalized, according to the U.S. Centers for Disease Control and Prevention (CDC).
The outbreak strain of E. coli O157:H7 was found in a sample of Tanimura & Antle Romaine Lettuce from a Walmart in Michigan, where 2 illnesses were reported, which led to a recall on November 6.
However, the CDC says “this data alone is not enough to prove a link in the outbreak.” The agency is still investigating whether the sick people actually ate this recalled romaine lettuce, or other products.
The CDC is also investigating 2 additional, unrelated outbreaks of E. coli infections with unknown sources.
One of the mysterious E. coli outbreaks infected at least 23 people in 12 states between August 17 and October 8. Ten people were hospitalized, including 2 who developed a type of kidney failure called Hemolytic Uremic Syndrome (HUS).
The other E. coli outbreak sickened at least 21 people in 8 states between June 6 and October 5, including 1 person from Michigan who died, and 1 person who developed HUS.
In both outbreaks, the strain of E. coli O157:H7 was previously linked to romaine lettuce, including one outbreak in 2018 and another outbreak in 2019. Even so, health officials have been unable to pinpoint a source because different foods can be contaminated by the same strain of E. coli.