Chopped romaine lettuce grown in the Yuma, AZ area is the likely source to date of this year’s only multistate E. coli O157: H7 outbreak, and it is not over.

The federal Centers for Disease Control and Prevention (CDC) in Atlanta Friday updated their report on the 11-state outbreak involving 35 confirmed E. coli case with 22 hospitalizations. “At this time, no common grower, supplier, distributor, or brand has been identified,” CDC’s new report says.

Naming the growing region, however, did bring a joint statement on the outbreak from the Produce Marketing Association, Arizona Leafy Greens Marketing Agreement, California Leafy Greens Marketing Agreement, United Fresh and Western Growers.

“We are cooperating fully with the government and working closely to further identify the specific source of this outbreak,” the joint statement said.  ” Specifically, government officials are advising consumers not to consume chopped, bagged romaine grown in Yuma.  At this time, this advisory only applies to chopped, bagged romaine, not other forms of romaine such as whole heads or hearts. This advisory also does not apply to romaine grown elsewhere, including California.  Consumers may check with their retailer and/or restaurant to assist them in identifying product origin.”

The industry groups said nearly all of the romaine lettuce now being harvested and shipped throughout the United States is from California growing areas and those are not implicated in the outbreak. “The leafy greens community takes the responsibility for producing fresh produce very seriously,” the statement said.  “Leafy greens food-safety programs in both California and Arizona are the most rigorous in today’s produce industry. Both programs include mandatory farm food safety practices, and frequent government audits to ensure those practices are being followed.”

For consumers, CDC said this means any store-bought chopped romaine lettuce purchased for home-made salads and salad mixings is best thrown out. Nor should consumers eat chopped romaine lettuce in restaurants unless they are sure the produce was grown outside the Yuma growing area.  Both restaurants and retailers should ask their suppliers about the source of their chopped romaine lettuce.

CDC, the U.S. Food and Drug Administration (FDA), and health and regulatory authorities in several states are involved the ongoing investigation.

The Shiga toxin-producing E.coli outbreak has seen three people develop the kidney-damaging failure called hemolytic uremic syndrome or HUS. No deaths have yet been attributed to the outbreak.
The size of the outbreak grew from 17 people in seven states on April 9, to the current count of 35 confirmed cases in 11 states as of April 13. Start-on dates for the illnesses were from March 22 to March 31, 2018, suggesting additional infections are likely.

Ages of those in outbreak range from 12 to 84 years of age; and 69 percent are female.

CDC suggests the outbreak is not over with illnesses after March 27, 2018, not yet included in the count. There is a two to a three-week time lag between the time a person becomes ill with E. coil and when the illness is reported up to CDC.

The chopped romaine lettuce outbreak is not related to the E. coli O157: H7 outbreak involving leafy greens that began in late 2017 and was officially closed out on Jan. 25, 2018. “People in the previous outbreak were infected with a different DNA fingerprint of E. coli O157: H7 bacteria,” CDC’s report says.

Based on epidemiologic evidence, chopped romaine lettuce is the likely source of the current outbreak. Twenty-six of 28 or 93 percent of people interviewed after becoming ill reported eating chopped romaine lettuce the week before they became sick.

That percentage was significantly higher than a survey of healthy people, where 46 percent eat chopped romaine lettuce during the previous week.

Restaurant sales were often the source of the chopped romaine lettuce that infected people with E. coli.
Most healthy people said the chopped romaine lettuce was an ingredient in a restaurant salad. Traceback investigations are ongoing to find the source of that product and preliminary findings are pointing to the Yuma growing area.

The leafy green E. coli O157: H7 outbreak ended up with 25 confirmed cases in 15 states and include nine hospitalizations and one death.  Like the current chopped romaine outbreak to date, the leafy green investigation did not result in any product being recalled.

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