The CDC added that the last date of harvest for the romaine lettuce from the Yuma growing region was April 16th.
Health officials say almost two dozen more cases of a food poisoning outbreak linked to romaine lettuce grown in Arizona have been reported. That means the contaminated lettuce is now past its 21-day shelf life.
All the cases had been linked to lettuce that came from the Yuma, Arizona growing region. The state health lab confirmed the link to the Yuma region, Rooney said.
The CDC has stopped advising consumers to throw away romaine lettuce if they can't confirm where it's from.
Health officials say there is a lag time of two to three weeks between when someone falls ill and when it's reported to the CDC. Of the 157 people who were ill that the CDC has information on, 75 have been hospitalized and 20 have developed hemolytic uremic syndrome (HUS), the form of kidney failure that can be fatal. "The most recent illnesses reported to CDC started when romaine lettuce from the Yuma growing region was likely still available in stores, restaurants, and in peoples' homes", the CDC said. The death in California remains the only one in this outbreak.
In scale, this outbreak is approaching that of the 2006 baby spinach E. coli outbreak that sickened more than 200 people and killed five.
The agency continues with its investigation to find the source of the contamination.