28 more people reported getting sick in connection with the E. coli outbreak linked to romaine lettuce. It takes time for illnesses to be confirmed, entered into a database and matched up with the "outbreak" strain of E. coli, leading to a lag between when cases happen and when they are reported, Chapman told Live Science.
It has added six from California, one from Florida, one from Georgia, one from IL, one from MA, 10 from Missouri, one from New Jersey, two from NY, two from North Dakota, one from Texas, one from Washington and one from Wisconsin.
The E. Coli outbreak continues to sweep the country. One person in required hospitalization, but all recovered.
The Public Health Agency of Canada states two of those six Canadians reported traveling into the US before falling sick because of E. coli O157, three became contaminated in Canada along with the rest of the situation is under investigation.
At least 64 people have been hospitalized in the United States, including 17 with kidney failure.
Still, it would be surprising if additional illnesses are reported with start dates in May, because that would be three weeks after the outbreak announcement and really "stretching out the shelf life of the product", Chapman said. By the end of May, it's possible that more cases will be recorded.
It develops within a week after E. coli symptoms first appear.
The U.S. Food and Drug Administration says romaine lettuce from the Yuma growing region in Arizona and California is no longer being produced and distributed, so the potential for exposure to contaminated lettuce is reduced.
"This percentage is significantly higher than results from a survey of healthy people in which 46 percent reported eating romaine lettuce in the week before they were interviewed", the CDC said. They include severe stomach cramps, diarrhea and vomiting.