The warning applies to whole heads and hearts of romaine, chopped romaine, as well as salads and salad mixes containing romaine lettuce.
A Metro Atlanta teen has been confirmed to be the first case of E.coli infection in the state.
The U.S. Centers for Disease Control and Prevention added 31 people to its tally of victims in the outbreak.
The CDC confirmed to Newsweek that this outbreak is the worst multi-state E. coli outbreak in the USA since 2006, when almost 200 people got sick from contaminated spinach. No deaths have been reported, and no food product or company has been forced to initiate a recall.
Georgia is one of three new states to report the illness, along with Colorado and South Dakota.
But what had health officials so concerned is that there "is a higher hospitalization rate than usual for E. coli O157:H7 infections, which is usually around 30 percent". It applies to lettuce from the grocery store, and from take-out and restaurants.
Half the 84 cases have resulted in hospitalizations, including nine for treatment of kidney failure, according to the CDC. The 16-year-old from rural Sacramento, Calif., had been eating salad every day the week before she got sick.
Panera Bread officials told "CBS This Morning" they "don't comment on pending litigation", but said they "have re-supplied with romaine from other regions".
In the meantime, the agency repeated its advice to consumers: "Do not eat or buy romaine lettuce unless you can confirm it is not from the Yuma, Arizona growing region". If you do not know whether the lettuce in a salad mix is romaine, do not eat it. Often times product labels do not identify growing regions.
Brittany Behm, a spokeswoman with the CDC's Division of Foodborne, Waterborne and Environmental Diseases, said "health officials are doing additional lab testing of this strain to test how severe of illness it can cause". Those symptoms include severe stomach cramps, diarrhea and vomiting.
"This bacteria can actually get inside the lettuce leaf", he said.