Ten cases of E.coli infection in Minnesota residents are now identified and linked to the multi-state outbreak.
Last week the FDA confirmed that the harvesting season was over for romaine in Yuma, and that any lettuce picked then has now expired.
Romaine lettuce is displayed on May 2, 2018 in San Anselmo, California.
The outbreak has now affected people in New Jersey, Connecticut, Pennsylvania, New York and almost half the rest of the US states.
The CDC said four more states - Florida, Minnesota, North Dakota and Texas - have been hit by the outbreak, bringing the total number of affected states to 29. Most people get diarrhea (often bloody), severe stomach cramps and vomiting.
The Yuma region grows the overwhelming majority of the lettuce and other leafy greens consumed in the United States in the winter months through early April, before shifting to California's Central Valley and Salinas Valley.
The organization is cautioning restaurants to stop serving romaine unless they're sure it's not coming from saidregion, while warning consumers to "not eat or buy romaine lettuce if you do not know where it was grown". People typically become ill two to five days after exposure, but this period can range from one to eight days.
"Of the 112 people interviewed, 102, or 91%, reported eating romaine lettuce in the week before their illness started", the CDC wrote on its website Wednesday. One person, who lived in California, has died. However, children younger than 10, the elderly, and those with compromised immune systems are at risk of developing complications.
Seventeen of the 64 people in the hospital have developed hemolytic uremic syndrome, a type of kidney failure, the CDC said. But the other 141 cases are still not linked to a farm, processor, distributor, grocery store, or restaurant.
The agency says if it is determined that contaminated romaine lettuce is in the Canadian market, the Canadian Food Inspection Agency will recall the product as required. People also should avoid salad mixes that include romaine.
The contaminated romaine distributed by Harrison was harvested between March 5 and March 16.