On April 10, the U.S. Food and Drug Administration and the U.S. Centers for Disease Control and Prevention (CDC) announced an outbreak of Shiga toxin-producing Escherichia coli O157:H7 affecting numerous people in different states. At the time of the agencys’ announcement, no food source had been identified.

As of April 13, the agencies have identified the food source as chopped romaine lettuce originating from the Yuma, AZ region. Since the original outbreak announcement, the number of cases increased to 35 sickened in 11 states. Twenty-two of those people were hospitalized, three of whom have developed a type of kidney failure called hemolytic uremic syndrome. No deaths have been reported

Despite narrowing down the food source, no common grower, supplier, distributor or brand has been identified by health officials. As such, no food products have been recalled in association with this outbreak.

Oddly, this is the second outbreak of its kind to occur in the U.S. this year. In January, a very similar outbreak occurred in both the U.S. and Canada. After an investigation, Canadian Health Officials declared their outbreak over after linking it to romaine lettuce. However, U.S. health officials stopped short of naming romaine lettuce, instead saying the outbreak was “likely” connected to “leafy greens”.

As for the current outbreak, CDC is urging any consumer who is in possession of store-bought chopped romaine lettuce (which may include salads and salad mixes containing chopped romaine lettuce) should not eat these items. Instead, they should be thrown away, even if some of it has already been eaten and no signs of illness have materialized. The agency also warns not to eat lettuce if you are not sure whether or not it is romaine. Before purchasing romaine lettuce at a grocery store or eating it at a restaurant, consumers should confirm with the store or restaurant that it is not chopped romaine lettuce from the Yuma, Arizona growing region. If you cannot confirm the source of the romaine lettuce, do not buy it or eat it.

As for restaurants and retailers, CDC says these establishments should not serve or sell any chopped romaine lettuce, including salads and salad mixes containing chopped romaine lettuce, from the Yuma, AZ growing region. Restaurants and retailers should ask their suppliers about the source of their chopped romaine lettuce.

The investigation is ongoing, and CDC will provide updates when more information is available.

More on E. coli and leafy greens:
U.S. Declares End to Leafy Green E. coli Outbreak
U.S. Says E. coli Outbreak "Likely" Leafy Greens While Canada Declares Outbreak Over
U.S. Officials Not Ready to Blame E. coli Outbreak on Lettuce

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