They have been added to one previously reported case in New York, The New York Times said.
The new cases came as the head of U.S. food safety efforts said it's possible the government will never track down the source of the outbreak. David Acheson, the Food and Drug Administration's "food safety czar," says that's because fresh produce like tomatoes aren't consistently labeled as to origin, and also because the outbreak, which sickened more than 277 people and hospitalized 43, is so widespread, the Chicago Tribune reported Wednesday.
Acheson said that definitively pinning down where the bacteria originated may be impossible because, unlike jars of peanut butter, which were also subjects of an outbreak, individual tomatoes typically don't have information about their origins.
"Off of that jar of peanut butter, you've got the history of that product," Acheson said, adding that even though some U.S. growers voluntarily identify boxes of their products, tracking a suspect batch is very difficult.
The FDA used harvest schedules in a process of elimination to narrow down their suspicions to southern Florida or Mexico.