In all, 172 individuals across 32 states have become ill since March 13.
The agency said the latest illnesses began May 2. Symptoms, which begin about three to four days after consuming the bacteria, can include watery or bloody diarrhea, fever, abdominal cramps, nausea and vomiting, according to the CDC.
At least 75 of those sickened have been hospitalized, and 20 have developed hemolytic uremic syndrome, a type of kidney failure.
Federal health officials have not been able to narrow the source of the E. coli contamination beyond stating that it is from romaine lettuce from the Yuma, Arizona, growing region.
The growing season there ended last month, and according to the US Food and Drug Administration, the last shipments of lettuce from there were harvested April 16.
However, federal health officials are continuing to investigate this outbreak.
“The ongoing traceback investigation indicates that the illnesses associated with this outbreak cannot be explained by a single grower, harvester, processor, or distributor,” the FDA said Wednesday. “FDA will focus on trying to identify factors that contributed to contamination of romaine across multiple supply chains. The agency is examining all possibilities, including that contamination may have occurred at any point along the growing, harvesting, packaging, and distribution chain before reaching consumers.”
News credit : Cnn