The nationwide outbreak of illnesses from eating romaine lettuce tainted with E. coli bacteria rose again, with 23 more cases reported in 13 states, the Centers for Disease Control and Prevention said Wednesday.
The 172 reported illnesses, which resulted in one death and 75 hosptializations, have been traced to lettuce harvested in April in the winter lettuce region around Yuma, Ariz., according to the CDC.
Iowa, Nebraska and Oregon newly joined the list of 32 states that have reported illnesses linked to romaine lettuce.
The CDC and Food and Drug Administration have struggled for more than a month to pinpoint a source for the contamination, which became evident in early April. No recall was issued.
One Yuma-area field, Harrison Farms, was identified as the supplier of whole romaine lettuce to prisoners who fell ill at a correctional facilitiy in Nome, Alaska. But authorities are not sure where in the supply chain the contamination might have occurred, and have said they are investigating more than a dozen additional sites.
"The last shipments of romaine lettuce from the Yuma growing region were harvested on April 16, 2018, and the harvest season is over," the CDC said. "It is unlikely that any romaine lettuce from the Yuma growing region is still available in stores or restaurants due to its 21-day shelf life."
The agency noted that it can take two to three weeks for cases to be reported.
With 39 cases and one death, California leads the outbreak, followed by Pennsylvania with 21, and Minnesota reporting 12 and Idaho, 11. The remaining cases counts were in the single digits.
Those states are Alaska, Arizona, Colorado, Connecticut, Florida, Georgia, lllinois, Iowa, Kentucky, Louisiana, Massachusetts, Michigan, Mississippi, Missouri, Montana, Nebraska, New Jersey, New York, North Dakota, Ohio, Oregon, South Dakota, Tennessee, Texas, Utah, Virginia, Washington and Wisconsin.
The outbreak is the worst since contaminated spinach linked to California's Salinas Valley sickened about 200 people in 2006.