Another round of romaine-connected E. coli outbreaks is over, according to the Food and Drug Administration and the federal Centers for Disease Control and Prevention.

Before the end came, infections of E. coli O157: H7 in 217 people saw every other person admitted to the hospital. Unlike other romaine-linked E. coli outbreaks since late 2017, there were no deaths during this round.

The largest outbreak this time involved E. coli infections linked to romaine lettuce grown in California’s Salinas Valley. It ended up sickening 167 people with the outbreak strain of E. coli O157: H7 in 27 states. The most recent illness onset date was Dec. 21, 2019.

The next three outbreaks might be one. CDC includes the outbreak linked to Fresh Express Sunflower Crist Chopped Salad Kits as a multistate outbreak. The Fresh Express salad kits, containing romaine, had a best-before date of Dec. 7, 2019. Ten people in five states were infected.

Fresh Express was further implicated in these events when the outbreak strain from the Salinas growing region showed up in an unopened bag of its Leafty Green Romaine. Wisconsin health officials made the discovery.

The Public Health Agency of Canada also reports 24 cases across six Canadian provinces that are the third romaine/E. coli event. And the fourth involves 11 cases associated with romaine consumption at a Seattle area restaurant chain.

FDA and CDC continue to treat the four events as separate outbreaks. If more traceback evidence existed, it might suggest otherwise.

The federal food detectives were at a disadvantage because the outbreaks occurred after the Salinas growing season. “When investigators arrived on the ranches, there was no romaine lettuce in the ground, and the fields had been plowed, as the growing season had already ended,” FDA reports.

“Investigators collected water, soil, and compost samples to be analyzed,” it said. “So far, sample results have come back negative for the three outbreak strains of E. coli. FDA did find a strain of E. coli that is unrelated to any illnesses in a soil sample.”

“This strain of E. coli was determined to be of low risk to people,” FDA continued. “Although this grower was determined to be a common supplier for all three outbreaks based on available supply chain information, the romaine lettuce from this grower does not explain all the illnesses seen in the three outbreaks.

FDA promises to keep investigating “throughout this year’s romaine lettuce planting, growing and harvesting seasons.” Those seasons essentially occur year-round, depending on the growing region.

Fresh Express tells consumers that Traceability is No. 5 on its seven rules for food safety.

“Another important component of an effective food safety program is the ability to trace leafy greens products back to where they are grown and forward to where they are distributed. We use coordinated bar-code tracking technology that’s second to none,” Fresh Express says, “Our extensive, fully integrated traceability system has been in place for many years.”

The FDA finding a common grower is “a notable development” in that the best industry and government could do previously was to identify a suspected growing region.

Also notable was 75,233-pound recall of salad products by Missa Bay LLC in Swedesboro, NJ. Those products contained lettuce from the same lot used in packaged salads containing E. coli O157: H7. Maryland health officials made that discovery and connected the dots.

Except for that specific recall, the public was warned not to eat romaine lettuce that was either of unknown origin or from the Salinas growing region. The outbreak’s end brings an end to those warnings as the government believes none of the suspect romaine remains on the market.

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