As the FDA awaits final results from extensive E. coli tests of romaine lettuce farms in one California growing region, it says outbreak illnesses are slowing, though two separate outbreaks have popped up.

“Because of the expansive nature of these outbreaks, our investigation remains a complicated work in progress, and it is too soon to draw definitive conclusions,” says Frank Yiannas, deputy commissioner for food policy and response.

Public health officials are investigating the sources for the three outbreaks with different E. coli strains:

• Outbreak that pointed to Salinas, Calif.: The FDA has warned people not to eat romaine from this major growing region because epidemiologic, laboratory and traceback evidence indicated that contaminated lettuce likely came from there. The Centers for Disease Control and Prevention reports 102 cases of illness in 23 states. The majority of samples from farms identified through initial traceback came back negative for the outbreak strain, the FDA says. However, final results from water, soil, soil amendments, scat and swab samples are pending, the agency notes. Also, Wisconsin health officials recently isolated E. coli O157:H7 from a bag of Fresh Express chopped romaine from Salinas.
• Fresh Express Sunflower Crisp Chopped Salad Kits: U.S. and Canadian health officials announced an outbreak linked to the product, with eight illnesses in the U.S. in three states. Canada reported 24 cases in six provinces. People should not eat the salad kits with UPC code 0 71279 30906 4, beginning with lot code Z, and best before dates through 07DEC19.
• Washington State restaurant chain: Another outbreak with 10 confirmed illness and three probable cases is associated with eating romaine at a local restaurant chain in mid-November.

“The FDA, CDC and our state partners have identified a common grower between each of the outbreaks, which is a notable development,” Yiannas says in the statement.

That reinforces traceback results, but it’s too early to determine whether other sources also may have been involved.

A lack of modernized food traceability causes a lag in public health officials’ ability to trace the source of contaminated foods, Yiannas says. The FDA will launch a New Era of Smarter Food Safety Blueprint early next year to outline how it will use technology advances to improve traces through the supply chain.

Read Yiannas’ full statement here outlining investigation procedures, traceback challenges and expected improvements.